Sel 751A Instruction Manual
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Sel 751A Instruction Manual

Feeder protection relay
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Table Of Contents
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Table of Contents

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SEL-751A
Feeder Protection Relay
20100129
*PM751A-01-NB*

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  • Page 1 SEL-751A Feeder Protection Relay Instruction Manual 20100129 *PM751A-01-NB*...
  • Page 2 © 2007–2010 Schweitzer Engineering Laboratories, Inc. All rights reserved. All brand or product names appearing in this document are the trademark or registered trademark of their respective holders. No SEL trademarks may be used without written permission. SEL products appearing in this document may be covered by US and Foreign patents.

  • Page 3: Table Of Contents

    Demand Metering ............................4.76 Logic Settings (SET L Command) ........................ 4.81 Global Settings (SET G Command) ......................4.92 Synchrophasor Measurement ........................4.94 Breaker Failure Setting..........................4.94 Arc-Flash Protection............................4.95 Analog Inputs .............................. 4.100 Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 4: Table Of Contents

    SEL-751A Settings Sheets Section 7: Communications Overview ................................. 7.1 Communications Interfaces ..........................7.1 Communications Protocols..........................7.11 SEL ASCII Protocol and Commands ......................7.13 Section 8: Front-Panel Operations Overview ................................. 8.1 Front-Panel Layout ............................8.1 Human-Machine Interface..........................8.2 Operation and Target LEDs ........................... 8.12 Section 9: Analyzing Events Overview .................................

  • Page 5: Table Of Contents

    Overview .................................B.1 Upgrade Instructions ............................B.1 Appendix C: SEL Communications Processors SEL Communications Protocols........................C.1 SEL Communications Processor ........................C.3 SEL Communications Processor and Relay Architecture ................C.5 SEL Communications Processor Example......................C.7 Appendix D: DNP3 Communications Overview ................................ D.1 Introduction to DNP3 ............................. D.1 DNP3 in the SEL-751A..........................
  • Page 6 This page intentionally left blank...
  • Page 7 List of Tables Table 1.1 Voltage Input Options......................1.13 R.Instruction Manual Table 1.2 SEL-751A Serial Port Settings..................... 1.17 Table 2.1 Communication Ports......................2.4 Table 2.2 Communication Card Interfaces and Connectors..............2.5 Table 2.3 3 AVI Voltage Card Terminal Designation................2.5 Table 2.4...
  • Page 8 Table 6.4 SET Command Editing Keystrokes..................6.5 Table 6.5 SET Command Format......................6.5 Table 7.1 SEL-751A Communications Port Interfaces................7.1 Table 7.2 EIA-232/EIA-485 Serial Port Pin Functions ................. 7.8 Table 7.3 Protocols Supported on the Various Ports ................7.11 Table 7.4 Serial Port Automatic Messages ..................

  • Page 9: Firmware

    Front-Panel Pushbutton Functions ..................8.5 Table 8.3 Possible Warning Conditions (Flashing TRIP LED) ............8.13 Table 8.4 SEL-751A Front-Panel Operator Control Functions ............8.15 Table 9.1 Event Types ..........................9.4 Table 9.2 Event Report Current and Voltage Columns ................9.7 Table 9.3...

  • Page 10: Instruction Manual

    SEL Communications Processor Port 1 Settings ..............C.7 Table C.5 SEL Communications Processor Data Collection Automessages..........C.8 Table C.6 SEL Communications Processor Port 1 Automatic Messaging Settings .......C.8 Table C.7 SEL Communications Processor Port 1 Region Map ............C.8 Table C.8 Communications Processor METER Region Map..............C.9 Table C.9...
  • Page 11 ACSI Models Conformance Statement ................F.31 Table F.31 ACSI Services Conformance Statement................F.32 Table H.1 PMU Settings in the SEL-751A for C37.118 Protocol in Global Settings ......H.4 Table H.2 SEL-751A Serial Port Settings for Synchrophasors ............. H.5 Table H.3 Synchrophasor Order in Data Stream (Voltages and Currents)..........
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  • Page 13 Figure 2.24 SEL-751A Provides Overcurrent Protection for an Industrial Distribution Feeder (Core-Balance Current Transformer Connected to Channel IN)........2.28 Figure 2.25 SEL-751A With an Arc-Flash Option Card and Fiber-Optic-Based Point-Sensor ....2.29 Figure 2.26 Jacketed-Fiber installation Example ..................2.30 Figure 2.27 Connecting Sensor Fibers to the Relay ................

  • Page 14: Overview

    Reclose Supervision Logic (Following Open Interval Time-Out) ........4.54 Figure 4.32 Reclose Supervision Limit Timer Operation................ 4.55 Figure 4.33 SEL-751A Relays Installed at Both Ends of a Transmission Line in a High-Speed Reclose Scheme.................... 4.57 Figure 4.34 Reclosing Relay States and General Operation..............4.60 Figure 4.35...

  • Page 15: Settings

    Figure 5.17 Plotted Breaker Maintenance Points for a 25 kV Circuit Breaker ........5.17 Figure 5.18 SEL-751A Breaker Maintenance Curve for a 25 kV Circuit Breaker ......... 5.18 Figure 5.19 Operation of SEL Control Equation Breaker Monitor Initiation Setting ..... 5.19 OGIC Figure 5.20...
  • Page 16 Ethernet Network Configuration With Ring Structure (Switched Mode)......7.4 Figure 7.4 IRIG-B Input (Relay Terminals B01–B02) ................7.6 Figure 7.5 IRIG-B Input Via EIA-232 Port 3 (SEL Communications Processor as Source) ....7.6 Figure 7.6 IRIG-B Input VIA EIA-232 Port 3 (SEL-2401/2404/2407 Time Source)......7.7 Figure 7.7 IRIG-B Input VIA Fiber-Optic EIA-232 Port 2 (SEL-2030/2032 Time Source) ....
  • Page 17 Multitiered SEL Communications Processor Architecture............C.4 Figure C.3 Enhancing Multidrop Networks With SEL Communications Processors......C.6 Figure C.4 Example of SEL Relay and SEL Communications Processor Configuration......C.7 Figure D.1 Application Confirmation Timing With URETRY n = 2 ............D.7 Figure D.2 Message Transmission Timing....................D.8 Figure D.3...
  • Page 18 This page intentionally left blank...
  • Page 19 Appendix C: SEL Communications Processors. Provides examples of how to use the SEL-751A with the SEL-2032, SEL-2030, and SEL-2020 Communications Processors for total substation automation solutions. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 20 Briefly describes the serial port commands that are fully described in Section 7: Communications. Conventions Typographic There are many ways to communicate with the SEL-751A. The three primary methods are: Conventions ➤ Using a command line interface on a PC terminal emulation window.
  • Page 21 Examples This instruction manual uses several example illustrations and instructions to explain how to effectively operate the SEL-751A. These examples are for demonstration purposes only; the firmware identification information or settings values included in these examples may not necessarily match those in the current version of your SEL-751A.
  • Page 22 (for low-voltage supply) Laser/LED Emitter The SEL-751A is a Class 1 LED Product and complies with IEC 60825- 1:1993 + A1:1997 + A2:2001. The following figure shows the compliance label that is located on the left side of the device (when facing the front of the device).
  • Page 23 Preface Safety and General Information The following figure shows the LED location specific to the SEL-751A (see Figure 2.10 for the complete rear-panel drawing). Fiber-Optic Ethernet Fiber-Optic Serial Port LED Port LEDs Arc-Flash Detection LEDs for Self-Test i4333a SEL-751A LED Locations LED Safety Warnings and Precautions ➤...
  • Page 24 Preface Safety and General Information Hazardous Locations The SEL-751A complies with UL 1604, CSA 22.2 No. 213 and EN 60079-15. In North Approvals America, the relay is approved for Class 1, Division 2, Groups A, B, C, D, and T4 in the –40°C to +70°C temperature range.
  • Page 25 Instructions for Use a mild soap or detergent solution and a damp cloth to carefully clean the SEL-751A chassis when necessary. Avoid using abrasive materials, polishing Cleaning and compounds, and harsh chemical solvents (such as xylene or acetone) on any Decontamination surface of the relay.
  • Page 26 This page intentionally left blank...
  • Page 27 (AFD)-based, and RTD-based protection are available as options. All relay models provide monitoring functions. This manual contains the information needed to install, set, test, operate, and maintain any SEL-751A. You need not review the entire manual to perform specific tasks. Features ➤...

  • Page 28: Models, Options, And Accessories

    Models, Options, and Accessories Models Complete ordering information is not provided in this instruction manual. See the latest SEL-751A Model Option Table at www.selinc.com, under SEL Literature, Ordering Information (Model Option Tables). Options and accessories are listed below. ➤...
  • Page 29 Four ac current inputs card (Slot Z) ➤ Protocols ➢ ® Modbus ➢ SEL ASCII and Compressed ASCII ➢ SEL Fast Meter, Fast Operate, Fast SER, Fast Message ➢ Ymodem File Transfer ➢ ITS ® SEL M IRRORED ➢ ®...
  • Page 30 With Monitoring Package With Monitoring and Advanced Metering and Protection Packages With 4-channel Arc-Flash Detector Inputs and Protection Accessories Contact your Technical Service Center or the SEL factory for additional detail and ordering information for the following accessories: ➤ External RTD protection ➢...

  • Page 31: Applications

    Wall-Mounting Kits ➤ Bezels for Retrofit ➤ Replacement Rear Connector Kit For all SEL-751A mounting accessories for competitor products, including adapter plates, visit http://www2.selinc.com/mounting_selector/. Applications Section 2: Installation includes ac and dc connection diagrams for various applications. The following is a list of possible application scenarios: ➤...

  • Page 32: Getting Started

    Understanding basic relay operation principles and methods will help you use the SEL-751A effectively. This section presents the fundamental knowledge you need to operate the SEL-751A, organized by task. These tasks help you become familiar with the relay and include the following: ➤...
  • Page 33 Station 1 Time Source: Internal Figure 1.2 Response Header Checking Use the STA serial port command to view the SEL-751A operational status. Analog channel dc offset and monitored component status are listed in the Relay Status status report depicted in Figure 1.3.

  • Page 34: Definitions

    DAT (Date Command) Viewing the Date Type DAT <Enter> at the prompt to view the date stored in the SEL-751A. If the date stored in the relay is July 29, 2003, and the DATE_F setting is MDY, the relay will reply:...
  • Page 35 Getting Started TIM (Time Command) Viewing the Time Enter TIM at the prompt to view the time stored in the SEL-751A. The relay will reply with the stored time. For example 13:52:44 This time is 1:52 p.m. (and 44 seconds).
  • Page 36 360 VA, cos φ = 0.3 VA Rating: Rated Supply Voltage: 24–48 Vdc Input Voltage Range: 19.2–52.8 Vdc Power Consumption: <20 W (dc) Interruptions: 10 ms @ 24 Vdc 50 ms @ 48 Vdc SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 37 2 mA (at 220–250 V) Single/Dual 10/100BASE-T copper (RJ-45 connector) Nominal DC Voltage: 4 mA (at 48–125 V) Single/Dual 100BASE-FX (LC connector) 10 mA (at 24 V) Rated Impulse Withstand Voltage (U 4000 V Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 38 0.5 J, 4.7 kV on power supply, contact I/O, ac current and voltage inputs Communications Protocols 0.5 J, 530 V on analog output SEL, Modbus, DNP3, FTP, TCP/IP, Telnet, IEC 61850, M IRRORED RFI and Interference Tests Communications, EVMSG, C37.118 (synchrophasors) and DeviceNet.
  • Page 39 (1 A nominal) Pickup/Dropout Time: <10 cycles Accuracy: ±5% of setting ±0.02 • I A secondary (Steady State pickup) Time Delay: 0.00–5.00 seconds, 0.01 seconds steps Pickup/Dropout Time: <1.5 cycles Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 40 25 ohm max. per lead Lead Length: <10 m to meet IEC 60255-22-1 and IEC 60255-22-5 Update Rate: <3 s Noise Immunity on RTD Inputs: up to 1.4 Vac (peak) at 50 Hz or greater frequency SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 41 SEL-751A. Use these drawings as a starting point for planning your particular relay application. The instructions for using the versatile front-panel custom label option are available on the SEL-751A product page on the SEL website. This allows you OGIC ® to use SEL control equations and slide-in configurable front-panel labels to change the function and identification of target LEDs.

  • Page 42: I/O Configuration

    Your SEL-751A offers flexibility in tailoring I/O to your specific application. In total, the SEL-751A has six rear-panel slots, labeled as Slots A, B, C, D, E, and Z. Slots A, B, and Z are base unit slots, each associated with a specific function.
  • Page 43 Ethernet port (P1) and dual copper Ethernet port (P1) that have Port 3 as an EIA-232 serial port and can input IRIG-B via the EIA-232 port and an SEL communications processor). IRIG-B input is also supported via Port 2 (optional EIA-232 fiber-optic serial port).
  • Page 44 EIA-485 serial port Port F supports the following protocols: ➤ BOOT ➤ ® Modbus RTU Slave ➤ SEL ASCII and Compressed ASCII ➤ SEL Settings File Transfer ➤ Event Messenger ➤ C37.118 (Synchrophasor Data) Port 1 (Ethernet) supports the following protocols: ➤...
  • Page 45 Supported in Slot E only, order this card when you have either single or three-phase (wye or delta) PTs. With a voltage card installed, (3 AVI) the SEL-751A tracks the frequency (using positive-sequence voltage) and samples at 16 times a cycle—see Processing Specifications on page 1.23 more information.
  • Page 46 Supported in Slot E only, order this card when you have voltage inputs including synchronism-check voltage input and station dc Card Option With battery monitor input. With a voltage card installed, the SEL-751A tracks the Monitoring Package frequency (using positive-sequence voltage) and samples at 16 times-a-cycle.
  • Page 47 You can order one of three neutral CT ratings, 1 A, 5 A, 50 mA, or 2.5 mA 0.05 A (1 A). (high sensitivity). With a current card installed, the SEL-751A tracks the frequency (using positive-sequence current) and samples at 16 times a cycle—...
  • Page 48 (3 DI/4 DO/1 AO) terminal allocation. Table 2.9 I/O (3 DI/4 DO/1 AO) Card Terminal Allocation Terminal Number Software Reference, Description 01, 02 OUTx01, driven by OUTx01 SEL equation OGIC 03, 04 OUTx02, driven by OUTx02 SEL equation OGIC...
  • Page 49 When an I/O board is moved from one slot to a different slot, the associated settings for the slot the card is moved from will be lost. For example, if a 4 DI/4 DO card is installed in Slot 4 (Slot D), the SEL settings OGIC OUT401-404 would be available.
  • Page 50 Also, a communications card installed in Slot C will be reflected as an empty slot in the part number. Use the Status command to view the part number. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 51 Figure 2.5 shows JMP4 selected as a current analog output. The current analog output selection is the default setting for JMP1 through JMP4. Figure 2.6 shows JMP1 selected as a voltage analog output. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 52 Password Bypassed A B C A B C JMP1 Remote Breaker Control Allowed A B C JMP1 BOOT Forced A B C Figure 2.7 Pins for Password, Breaker Control, and SEL Jumper BOOT SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 53 2.13 I/O Configuration Pins labeled A bypass the password requirement, pins labeled B enable breaker control, and pins labeled C force the relay to the SEL operating system called SEL . In the unlikely event that the SEL-751A suffers an BOOT internal failure, communications with the relay may be compromised.
  • Page 54 Card 10: Main Board with Single, Copper Ethernet, Fiber-Optic Serial, and EIA-232 Rear Ports Card 11: Main Board with Dual, Fiber-Optic Ethernet, Fiber-Op- tic Serial, and EIA-232 Rear Ports Figure 2.8 Rear-Panel Connections of Selected Cards SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 55: Rear-Panel Connections

    Installation 2.15 Rear-Panel Connections Rear-Panel Connections Rear-Panel and The physical layout of the connectors on the rear-panel and side-panel diagrams of three sample configurations of the SEL-751A are shown in Side-Panel Diagrams Figure 2.9, Figure 2.10, and Figure 2.11. 710_IM_0133_IRIG-BRP-B_i3970c.eps...
  • Page 56 Figure 2.10 Fiber-Optic Serial, Ethernet, 8 DI, RTD, and 4 AI/4 AO Option i4247a i4246a (A) Rear-Panel Layout (B) Side-Panel Input and Output Designations Figure 2.11 Dual Fiber-Optic Ethernet, Fiber-Optic Serial, DeviceNet, Fast Hybrid 4 DI/4 DO, and Voltage Option With Monitoring Package SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 57 EIA-485 (4A) and an EIA-232 (4C) port, only one port is available at a time. Use the Port 4 communications interface COMMINF setting to select between EIA-485 and EIA-232. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 58 SEL-2812MT Transceiver to connect to the SEL-2030 or SEL-2032 and bring IRIG-B signal with the EIA-232 input. Use a fiber-optic cable pair with ST connectors (C805 or C807) to connect to the Port 2 on the SEL-751A. Refer to Section 7: Communications for details on IRIG-B connections examples and on SEL-2401/2407/2404 for time source.
  • Page 59 48, 110, 125, 220, or 250 Vac/Vdc. Standard required to connect the SEL with OGIC inputs IN101/102 may have a different an SEL-2600 series RTD Module. This rating than the optional IN401/402/403/404 fiber-optic cable should be 1000 meters (not shown). or shorter.

  • Page 60: Ac/Dc Control Connection Diagrams

    ➤ The relay coil is energized continuously if the SEL-751A is powered and operational. ➤ When the SEL-751A generates a trip signal, the relay coil is de- energized. ➤ The relay coil is also de-energized if the SEL-751A power supply voltage is removed or if the SEL-751A fails (self-test status is FAIL).
  • Page 61 Single Phase-Neutral VT Connection SEL-751A Single Phase-Phase VT Connection SEL-751A Figure 2.17 Single-Phase Voltage Connections Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 62 2.22 Installation AC/DC Control Connection Diagrams Direct Connection F1, F2, and F3 are fuses SEL-751A Wye-Wye VT Connection SEL-751A Open-Delta VT Connection SEL-751A Figure 2.18 Voltage Connections SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 63 Station DC Battery Use the station dc battery monitor (one of the options available with the Voltage Card options) in the SEL-751A to alarm for undervoltage and Monitor overvoltage dc battery conditions and to view how station dc battery voltage fluctuates during tripping, closing, and other dc control functions.
  • Page 64 ). But in this residual connection example, the neutral ground and residual ground overcurrent elements operate the same because Figure 2.20 SEL-751A Provides Overcurrent Protection and Reclosing for a Distribution Feeder (Includes Fast Bus Trip Scheme) (Delta-Connected PTs) SEL-751A Relay...
  • Page 65 Although automatic reclosing is probably not needed in this example, output contact OUT102 can close the ciruit breaker via initiation from various means (serial port communications, optoisolated input assertion, etc.) with desired supervision (e.g., synchronism check). Figure 2.21 SEL-751A Provides Overcurrent Protection for a Distribution Bus (Includes Fast Bus Trip Scheme) (Wye-Connected PTs) Date Code 20100129...
  • Page 66 Voltage option is needed for voltage elements and metering (e.g., voltage, KW, KVAR). INxxx and OUTxxx indicate user- configurable optional digital inputs and outputs. For sensitive earth fault (SEF) applications, the SEL-751A should be ordered with Channel IN rated at 2.5 mA nominal. See current input specifications in the subsection Specifications, General on page 1.20.
  • Page 67 Voltage option is needed for voltage elements and metering (e.g., voltage, KW, KVAR). INxxx and OUTxxx indicate user- configurable optional digital inputs and outputs. Figure 2.23 SEL-751A Provides Overcurrent Protection for a Transformer Bank With a Tertiary Winding (Wye-Connected PTs)
  • Page 68 Pass neutral (N) through the core-balance CT only if the neutral is brought out and it is grounded only at the source. For sensitive earth fault (SEF) applications, the SEL-751A should be ordered with Channel IN rated at 2.5 mA nominal.

  • Page 69: Arc-Flash Protection: System Installation

    I/O designations for a relay model with the 3 AVI/4 AFDI card for arc-flash protection. Figure 2.25 SEL-751A With an Arc-Flash Option Card and Fiber-Optic- Based Point-Sensor Light-Sensor An arc-flash system installation starts by selecting the best sensor location and the safest path for bringing the sensor fibers back to the relay.
  • Page 70 Although easily detected by the sensor diagnostics, such problems can be eliminated through careful installation planning. Once routed, fiber sensors are connected to the SEL-751A relay as shown in Figure 2.27.
  • Page 71 60° 290° 70° 280° 80° 270° 90° 260° 100° 250° 110° 240° 120° 230° 130° 220° 140° 210° 150° 200° 160° 190° 170° 180° Figure 2.30 Point-Sensor Directivity (0–360° Around the Mounting Plane) Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 72 70° 280° 80° 270° 90° 260° 100° 250° 110° 240° 120° 230° 130° 220° 140° 210° 150° 200° 160° 190° 170° 180° Figure 2.32 Point-Sensor Directivity (Left to Right, Above the Mounting Plane) SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 73 For correct operation, a bare-fiber sensor must be located within 2 m of the arcing site, with at least 0.5 m of the fiber exposed to the light. The maximum length of the bare-fiber sensor is limited to 70 m and includes both, bare- and Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 74 (outgoing) feeders. All three feeders are protected with an SEL-751A relay controlling breakers 1, 2, and 3. Radial feeder breakers 2 and 3 must be tripped for downstream faults, normally located in the outgoing cable termination compartment.

  • Page 75: Upgrade Instructions

    Field Serviceability LS1—LS4 are arc-flash detection inputs, point or bare-fiber sensors. Figure 2.37 Switchgear Application Example Field Serviceability The SEL-751A firmware may be upgraded in the field; refer to Appendix B: Firmware Upgrade Instructions for firmware upgrade instructions. You may...
  • Page 76 Step 6. Install the new battery with the positive (+) side facing up. Step 7. Insert the printed circuit board into Slot B. Step 8. Replace the relay rear panel and energize the relay. Step 9. Set the relay date and time. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 77 Table 3.2 QuickSet SEL-5030 Software ERATOR Terminal Provides a direct connection to the SEL device. Use this communication method to inter- face directly with the device. Rules-Based Settings Editor Provides on-line or off-line relay settings that include interdependency checks. Use this feature to create and manage settings for multiple relays in a database.

  • Page 78: Setup

    ERATOR Communications communications Port 1 through Port 4, or QuickSet uses ERATOR relay Port F (front panel) to communicate with the SEL-751A. Perform the following steps to configure QuickSet to communicate ERATOR effectively with the relay Step 1. Select Communications from the...
  • Page 79 PC Software Setup Figure 3.2 Serial Port Communication Parameters Dialog Box Figure 3.3 Network Communication Parameters Dialog Box Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 80: Terminal

    "DEVCODE=69","0316" "PARTNO=751A01B6X3X7183021X","06D9" "CONFIG=11251201","03F0" "iedName =TEMPLATE","05DC" "type =SEL_751A","04B0" "configVersion =ICD-751A-R100-V0-Z001001-D20070326","0D75" Figure 3.5 Device Response to the ID Command Locate and record the Z number (Z001001) in the FID string. The first portion of the Z number (Z001…) determines the QuickSet relay...

  • Page 81: Settings Database Management And Drivers

    > Database Manager. A dialog box appears. The default database file already configured in ERATOR QuickSet is Relay.rdb. This database contains example settings files for the SEL products with which you can use QuickSet. ERATOR Step 2. Enter descriptions for the database and for each...
  • Page 82 ERATOR relay efficient. However, you do not have to use QuickSet to ERATOR configure the SEL-751A; you can use an ASCII terminal or a computer running terminal emulation software. QuickSet provides the ERATOR OGIC ® advantages of rules-based settings checks, SEL...
  • Page 83 FID string to create a particular version of settings. To get started making SEL-751A settings with the Settings Editor in the Editor Mode, select File > New from the main menu bar, and SEL-751A and 004 from the Settings Editor Selection window as shown in Figure 3.6.
  • Page 84 When the Read menu item is selected, QuickSet reads the ERATOR device settings from a connected device. As QuickSet reads ERATOR the device, a Transfer Status window appears. QuickSet uses ERATOR serial protocols to read settings from SEL devices. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 85 (Logic Settings > performance. QuickSet simplifies this process with the ERATOR Enable) before using OGIC Expression Builder, a rules-based editor for programming SEL control Expression Builder. OGIC equations. The Expression Builder organizes device elements, analog quantities, and SEL control equation variables.
  • Page 86 Select Send from the File menu. In the dialog box that opens, select the settings section you want transferred to the relay by checking the appropriate box. SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 87: Event Analysis

    QuickSet has integrated analysis tools that help you retrieve ERATOR information about relay operations quickly and easily. Use the event information that the SEL-751A stores to evaluate the performance of a system (select Tools > Events > Get Event Files). Figure 3.10 shows composite screens for retrieving events.

  • Page 88: Meter And Control

    QuickSet should save the event record. ERATOR View Event Files To view the saved events, you need the SEL-5601 software package. Use the View Event Files function from the Tools > Events menu to select the event you want to view (...
  • Page 89 The front-panel LEDs display the status of the 16 front-panel LEDs. Use the front-panel settings to change the front-panel LED assignment. Figure 3.12 Device Overview Screen The Fundamental, Min/Max, Energy, etc., screens display the corresponding values. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 90 If supported, you can run arc-flash sensor diagnostic tests. Figure 3.13 Control Screen To control the Remote bits, click on the appropriate square, then select the operation from the box shown in Figure 3.14. Figure 3.14 Remote Operation Selection SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 91: Help

    Help Description General QuickSet Select Help from the main menu bar ERATOR SEL-751A Settings Select Settings Help from the Help menu bar while the Settings Editor is open. Database Manager Select Help from the bottom of the Database Manager window...
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  • Page 93 Protection and Logic Functions Overview NOTE: Each SEL-751A is shipped This section describes the SEL-751A Feeder Protection Relay settings, with default factory settings. Calculate including the protection elements and basic functions, control I/O logic, as the settings for your application to...
  • Page 94 (SEL-751A Settings Sheets) and various methods of accessing them. All current and voltage settings in the SEL-751A are in secondary. NOTE: The DeviceNet port You can enter the settings by using the front-panel function (see...

  • Page 95: Application Data

    Protection and Logic Functions Application Data Application Data It is faster and easier for you to calculate settings for the SEL-751A if you collect the following information before you begin: ➤ Highest expected load current ➤ Current transformer primary and secondary ratings and connections ➤...
  • Page 96 Balanced voltages are assumed for power, power factor, VG, and 3V2 metering. Relays that are not equipped with phase voltage inputs hide these settings and disable voltage-based protection and metering functions. SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 97: Basic Protection

    Table 4.7 and in Figure 4.1. Each element can be torque controlled using appropriate SEL control OGIC equations (e.g., when 50P1TC := IN401, the 50P1 element will be operational only if IN401 is asserted). Table 4.4 Maximum Phase Overcurrent Settings...
  • Page 98 For any phase instantaneous overcurrent element in the SEL-751A relay set above eight times the relay current input rating (40 A in a 5 A relay), the overcurrent element also operates on the output of a bipolar peak detector if the current waveform is highly distorted, as is the case with severe CT saturation.
  • Page 99 Torque Control switch position = Closed when corresponding control bit is asserted (e.g., 50P1TC = 1), Open when it is de-asserted. x = 2, 3, or 4 n = 1, 2, 3, or 4 Figure 4.1 Instantaneous Overcurrent Element Logic Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 100 The resistor is sized to limit the current to 10 A primary. The three feeder leads are passed through the window of a 10:1 core-balance CT. The CT secondary is connected to the SEL-751A current input (terminals Z07, Z08), as shown in Figure 4.2.
  • Page 101 51_MR respectively, each assumed equal to zero). Use the 51_CT if you want to raise the curves by a constant time. Also, you can use the 51_MR if you want to ensure the curve times no faster than a minimum response time. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 102 4.10 Protection and Logic Functions Basic Protection Each element can be torque controlled using appropriate SEL equations OGIC (e.g., when 51P1TC := IN401 the 51P1 element will be operational only if IN401 is asserted). Table 4.8 Phase A, B, and C Time-Overcurrent Settings...
  • Page 103 Setting Range Factory Default TOC TRIP LVL OFF, 0.50–16.00 A 51P1P := 6.00 0.10–3.20 A 51P1P := 1.2 TOC CURVE SEL U1, U2, U3, U4, U5, C1, C2, 51P1C := U3 C3, C4, C5 TOC TIME DIAL 0.50–15.00 51P1TD := 3.00 0.05–1.00...
  • Page 104 Setting Range Factory Default TOC TRIP LVL OFF, 0.50–16.00 A 51QP := 6.00 0.10–3.20 A 51QP := 1.2 TOC CURVE SEL U1, U2, U3, U4, U5, C1, C2, 51QC := U3 C3, C4, C5 TOC TIME DIAL 0.50–15.00 51QTD := 3.00 0.05–1.00...
  • Page 105 Factory Default TOC TRIP LVL OFF, 0.50–16.00 A 51N1P := OFF 0.10–3.20 A 0.13–2.00 mA 5.0–160.0 mA TOC CURVE SEL U1, U2, U3, U4, U5, 51N1C := U3 C1, C2, C3, C4, C5 TOC TIME DIAL 0.50–15.00 51N1TD := 1.50 0.05–1.00...
  • Page 106 Setting Range Factory Default TOC TRIP LVL OFF, 0.50–16.00 A 51G1P := 0.50 0.10–3.20 A 51G1P := 0.10 TOC CURVE SEL U1, U2, U3, U4, U5, C1, C2, 51G1C := U3 C3, C4, C5 TOC TIME DIAL 0.50–15.00 51G1TD := 1.50 0.05–1.00...
  • Page 107 Basic Protection Table 4.12 Residual Time-Overcurrent Settings (Sheet 2 of 2) Setting Name := Setting Prompt Setting Range Factory Default TOC CURVE SEL U1, U2, U3, U4, U5, C1, C2, 51G2C := U3 C3, C4, C5 TOC TIME DIAL 0.50–15.00 51G2TD := 1.50...
  • Page 108 ------------- - • ------------- - • ⎝ ⎠ ⎝ ⎠ – – C5 (Short-Time Inverse) Figure 4.17 ⎛ 0.05 ⎞ ⎛ 4.85 ⎞ ---------------------- • ---------------- • ⎝ ⎠ ⎝ ⎠ 0.04 – – SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 109 3.00 30 (25) 2.00 15 (12.5) 1.00 6 (5) 0.50 3 (2.5) .5 .6 .7 .8 .9 1 5 6 7 8 9 Multiples of Pickup Figure 4.8 U.S. Moderately Inverse Curve: U1 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 110 4.00 3.00 30 (25) 2.00 15 (12.5) 1.00 6 (5) 0.50 3 (2.5) .5 .6 .7 .8 .9 1 5 6 7 8 9 Multiples of Pickup Figure 4.9 U.S. Inverse Curve: U2 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 111 30 (25) 4.00 3.00 15 (12.5) 2.00 1.00 6 (5) 0.50 3 (2.5) .5 .6 .7 .8 .9 1 5 6 7 8 9 Multiples of Pickup Figure 4.10 U.S. Very Inverse Curve: U3 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 112 6.00 15 (12.5) 5.00 4.00 3.00 6 (5) 2.00 3 (2.5) 1.00 0.50 .5 .6 .7 .8 .9 1 6 7 8 9 Multiples of Pickup Figure 4.11 U.S. Extremely Inverse Curve: U4 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 113 30 (25) 8.00 6.00 5.00 15 (12.5) 4.00 3.00 2.00 6 (5) 1.00 3 (2.5) 0.50 .5 .6 .7 .8 6 7 8 9 Multiples of Pickup Figure 4.12 U.S. Short-Time Inverse Curve: U5 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 114 30 (25) 0.20 15 (12.5) 0.10 0.05 6 (5) 3 (2.5) .5 .6 .7 .8 .9 1 5 6 7 8 9 Multiples of Pickup Figure 4.13 IEC Class A Curve (Standard Inverse): C1 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 115 15 (12.5) 0.50 0.40 0.30 6 (5) 0.20 3 (2.5) 0.10 0.05 .5 .6 .7 .8 .9 1 6 7 8 9 Multiples of Pickup Figure 4.14 IEC Class B Curve (Very Inverse): C2 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 116 0.80 0.70 0.60 3 (2.5) 0.50 0.40 0.30 0.20 0.10 0.05 .5 .6 .7 .8 .9 1 6 7 8 9 Multiples of Pickup Figure 4.15 IEC Class C Curve (Extremely Inverse): C3 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 117 1500 (1250) 600 (500) 300 (250) 1.00 0.90 0.80 0.70 0.60 150 (125) 0.50 0.40 0.30 60 (50) 0.20 30 (25) 0.10 0.05 Multiples of Pickup Figure 4.16 IEC Long-Time Inverse Curve: C4 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 118 15 (12.5) 0.70 0.60 0.50 0.40 0.30 6 (5) 0.20 3 (2.5) 0.10 0.05 .5 .6 .7 .8 .9 6 7 8 9 Multiples of Pickup Figure 4.17 IEC Short-Time Inverse Curve: C5 SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 119: Rtd-Based Protection

    Protection and Logic Functions 4.27 RTD-Based Protection RTD-Based Protection RTD Input Function When you connect an SEL-2600 RTD Module or order the internal RTD card option, the SEL-751A offers several protection and monitoring functions, settings for which are described in Table 4.15. See Figure 2.13...
  • Page 120 120-ohm nickel (NI120) ➤ 10-ohm copper (CU10) RTD Trip/Warning Levels The SEL-751A provides temperature warnings and trips through use of the RTD temperature measurements and the warning and trip temperature settings Table 4.15. The relay issues a winding temperature warning if any of the healthy winding RTDs (RTD location setting equals WDG) indicate a temperature greater than the relay RTD warning temperature setting.

  • Page 121: Voltage-Based Protection

    UVS LEVEL 1 OFF, 2.00–300.00 V 27S1P := OFF UVS DELAY 1 0.0–120.0 sec 27S1D := 0.5 UVS LEVEL 2 OFF, 2.00–300.00 V 27S2P := OFF UVS DELAY 2 0.0–120.0 sec 27S2D := 0.5 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 122 OVS DELAY 2 0.0–120.0 sec 59S2D := 0.5 NOTE: The under- and overvoltage When you connect the SEL-751A voltage inputs to phase-to-phase connected level settings 27P and 59P are in per VTs (single-phase or three-phase), as in Figure 2.17 Figure 2.18, the relay...
  • Page 123 27P1T |VPP| min |VP| min 27P2 27P2 27P2D 27P2D 27P2P • Vnm 27P2P • Vnm 27P2T 27P2T 27S1P, 27S2P, 27P1P, 27P2P = Settings Vnm = Effective Nominal Voltage Figure 4.18 Undervoltage Element Logic Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 124 59Q2P 59Q2P 59Q2T 59Q2T |3V0| 59G1 59G1D 59G1P 59G1T 59G2 59G2D 59G2P 59G2T 59S1P, 59S2P, 59P1P, 59P2P, 59Q1P, 59Q2P, 59G1P, 59G2P = Settings Vnm = Effective Nominal Voltage Figure 4.19 Overvoltage Element Logic SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 125 Angle Difference Slip Calculator—to Figure 4.21 Frequency Calculator Slip Slip Frequency Absolute Value Frequency Element Setting Maximum Slip Frequency to Figure 4.21 25SF Figure 4.20 Synchronism-Check Voltage Window and Slip Frequency Elements Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 126 Angle Difference Increasing Last Check of Setting OGIC 79CLS (w) q From Figure 4.20; w see Figure 4.31. Figure 4.21 Synchronism-Check Elements These synchronism-check elements are explained in detail in the following text. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 127 VS cannot be in phase with VA, VB, or VC, the angle setting := VA or SYNCPH := 0). choices (0, 30, …, 300, or 330 degrees) are referenced to VA. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 128 (1.732*PTRS). This will be 0.58 if the PTR and PTRS are equal. See the Application Guide entitled Compensate for Constant Phase Angle Difference in Synchronism Check with the SEL-351 Relay Family (also applies to SEL-751A) for more information on setting SYNCPH with an angle setting. Synchronism-Check Elements Voltage Inputs...
  • Page 129 4.20. The synchronism-check element Slip Frequency Calculator in Figure 4.20 runs if voltages VP and VS are healthy (59VP and 59VS asserted to logical 1) and the SEL control equation setting OGIC BSYNCH (Block Synchronism Check) is deasserted (= logical 0). The Slip Frequency Calculator output is: Slip Frequency = fP –...
  • Page 130 VP and VS are “slipping” with respect to one another. Thus, synchronism- check elements 25A1 or 25A2 assert to logical 1 if the Angle Difference is less than corresponding maximum angle setting 25ANG1 or 25ANG2. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 131 4.22). The Angle Difference Calculator calculates the Angle Difference between voltages VP and VS, compensated with the breaker close time: Angle Difference = |(∠VP – ∠VS) + [(fP – fS) • TCLOSD • (1 / 1000) • (360°/slip cycle)]| Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 132 SV06 := 25A1 CL := CC and SV06T Set SV06PU with enough pickup delay to ensure that the slip frequency is low enough for the circuit breaker to close within the synchronism-check window. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 133 4.32). Refer to the top of Figure 4.31. If timer 79CLSD is set to zero (79CLSD := 0.00), SEL control equation setting 79CLS OGIC (Reclose Supervision) is checked only once to see if it is asserted to logical 1. If it is not asserted to logical 1, the relay goes to the Lockout State.
  • Page 134 Power Elements You can enable up to two independent three-phase power elements in the SEL-751A relay. Each enabled element can be set to detect real power or reactive power. When voltage inputs to the relay are from delta connected PTs or when single voltage input is used, the relay cannot account for unbalance in the voltages in calculating the power.
  • Page 135 Where n = 1 or 2 |V AB | 3PWRnT Setting Switch A Switch B PWRnT Position Position +WATTS |V BC | –WATTS +VARS –VARS 20 V Figure 4.23 Three-Phase Power Elements Logic Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 136 The two power element time delay settings (PWR1D and PWR2D) can be set to have no intentional delay for testing purposes. For protection applications involving the power element Relay Word bits, SEL recommends a minimum time delay setting of 0.1 second for general applications. The classical power calculation is a product of voltage and current, to determine the real and reactive power quantities.
  • Page 137 Refer to Figure 5.1 for the relay power measurement convention. Relay Word 55DLY Measured Power Factor PF Leading Settings Relay 55LDAP Word Bits 55AD 55LGAP 55LDTP 55TD 55LGTP Figure 4.25 Power Factor Elements Logic Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 138 Protection and Logic Functions Voltage-Based Protection Loss-of-Potential The SEL-751A sets Relay Word bit LOP (loss-of-potential) upon detecting a loss of relay ac voltage input such as that caused by blown potential fuses or (LOP) Protection by the operation of molded-case circuit breakers. Because accurate relaying...

  • Page 139: Frequency Protection

    81D4TD := 1.00 FREQ5 TRIP LEVEL OFF, 20.00–70.00 Hz 81D5TP := OFF FREQ5 TRIP DELAY 0.00–240.00 81D5TD := 1.00 FREQ6 TRIP LEVEL OFF, 20.00–70.00 Hz 81D6TP := OFF FREQ6 TRIP DELAY 0.00–240.00 81D6TD := 1.00 Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 140: Rate-Of-Change Of Frequency Protection

    Rate-of-Change of Frequency Protection NOTE: The relay measures system The SEL-751A provides six trip over- or underfrequency elements with frequency for these elements with the independent level and time-delay settings. When an element level setting is positive-sequence voltage if the...
  • Page 141 Use E81R setting to enable number of the elements desired, Figure 4.28 shows the element logic. The SEL-751A measures frequency (mf1) and second frequency (mf2) after a time window (dt) determined by Trip Level setting (81RnTP). Hysteresis is such that pickup is 100% of 81RnTP setting and dropout is 95%.

  • Page 142: Trip/Close Logic

    OR 55T OR REMTRIP OR SV01 OR OC OR SV04T REMTRIP := 0 REMOTE TRIP EQN ULTRIP := NOT (51P1P OR UNLATCH TRIP 51G1P OR 51N1P OR 52A) 52A := 0 BREAKER STATUS SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 143 UNLATCH CLOSE NOTE: The factory default The SEL-751A tripping logic is designed to trip the circuit breakers. The relay assignment of the Relay Word bit TRIP logic lets you define the conditions that cause a trip, the conditions that is the output OUT103. See Table 4.38...
  • Page 144 52A Breaker Status Conditions SEL Control Equation OGIC You can connect an auxiliary contact of the breaker to the relay. The SEL OGIC control equation 52A allows you to configure the relay for either 52b or 52a contact input (or other contact that indicates a closed breaker). The factory default setting assumes no auxiliary contact connection (52A := 0).
  • Page 145 Figure 4.31 Figure 4.30 Close Logic CL Close SEL Control Equation OGIC The SEL-751A Close Logic offers three ways to close the circuit breaker: ➤ Conditions mapped to CL ➤ Front-panel or serial port (including Modbus and DeviceNet) CLOSE command ➤...

  • Page 146: Reclose Supervision Logic

    Pulses (logical 1) for one The above logic satisfies most processing interval and applications. drives the reclose state to lockout if SEL control OGIC Operation of Reclose Supervision Logic if equation setting 79CLS is not timer setting 79CLSD is set:...
  • Page 147 79CLSD := 0.00 With this setting, the logic in the top of Figure 4.31 is operative. When an open interval times out, the SEL control equation reclose supervision OGIC setting 79CLS is checked just once. Date Code 20100129...
  • Page 148 79CLSD := 1.00 second With this setting, the logic in the bottom of Figure 4.31 is operative. When an open interval times out, the SEL control equation reclose supervision OGIC setting 79CLS is then checked for a time window equal to setting 79CLSD.
  • Page 149 Refer to the top of Figure 4.31 Figure 4.33 SEL-751A relays are installed at both ends of a transmission line in a high-speed reclose scheme. After both circuit breakers open for a line fault, the SEL-751A(1) recloses circuit breaker 52/1 first, followed by the SEL-751A(2) reclosing circuit breaker 52/2, after a synchronism check across circuit breaker 52/2.
  • Page 150 79STL := 0 The SEL-751A(2) starts open interval timing after circuit breaker 52/1 at the remote end has reenergized the line. The SEL-751A(2) has to see Bus 2 hot, transmission line hot, and in synchronism across open circuit breaker 52/2 for open interval timing to begin.

  • Page 151: Reclose Logic

    Lockout State. Reclose Logic Note that input: Reclosing Relay Open Interval Time-Out Figure 4.31 is the logic input that is qualified by SEL control equation OGIC setting 79CLS, and then propagated on to the close logic in Figure 4.30 automatically reclose a circuit breaker.
  • Page 152 States and General Operation Reset State The circuit breaker has been closed for a qualifying reset time. The SEL-751A is ready to go through an automatic reclosing sequence in the reclose cycle state if the circuit breaker trips open and reclose initiation is successful.
  • Page 153 The shot counter is equal to or greater than the last shot at time of reclose initiation (e.g., all automatic reclosing attempts are unsuccessful—see Figure 4.32). ➤ Reclose initiation is unsuccessful because of SEL control OGIC equation setting 79RIS [see Reclose Initiate and Reclose Initiate Supervision Settings (79RI and 79RIS, Respectively) on page 4.66].
  • Page 154 For example, if 52A := IN101, a 52a circuit breaker auxiliary contact is connected to input IN101. If the reclosing relay does not exist, the close logic still operates, allowing closing to take place via SEL control equation OGIC setting CL (close conditions, other than automatic reclosing).
  • Page 155 79BRS := TRIP SEQ COORDINATION 79SEQ := 0 RCLS SUPERVISION 79CLS := 1 The operation of open interval timers is affected by SEL control equation OGIC settings discussed later in this section. Open Interval Timers The reclose enable setting, E79, determines the number of open interval time settings that can be set.
  • Page 156 Reset Timer The reset timer qualifies circuit breaker closure before taking the relay to the Reset State from the Reclose Cycle State or the Lockout State. Circuit breaker status is determined by the SEL control equation setting 52A. (See Trip/ OGIC Close Logic on page 4.50...
  • Page 157 The 79RSD and 79RSLD settings are set independently (setting 79RSLD can even be set greater than setting 79RSD, if desired). SEL control equation OGIC...
  • Page 158 1) at the instant of the first trip of the auto-reclose cycle in order for the SEL-751A to successfully initiate reclosing and start timing on the first open interval. The SEL-751A is not yet in the reclose cycle state (79CY = logical 0) at the instant of the first trip.
  • Page 159 SEL-751A sees the circuit breaker close. If a flashover occurs in a circuit breaker tank during an open interval (circuit breaker open and the SEL-751A calls for a trip), the SEL-751A goes immediately to lockout. EXAMPLE 4.8 Additional Settings Example The preceding settings example initiates open interval timing on rising edge of the TRIP Relay Word bit.
  • Page 160 4.67). Then the drive-to-lockout condition overlaps reclose initiation and the SEL-751A stays in lockout after the breaker trips open. When 79DLS = logical 1, the reclosing relay goes to the last shot, if the shot counter is not at a shot value greater than or equal to the calculated last shot...
  • Page 161 79STL = logical 0, open interval timing resumes where it left off. Use the OPTMN Relay Word bit to monitor open interval timing (see Monitoring Open Interval and Reset Timing on page 4.65). Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 162 50P2P. EXAMPLE 4.13 Additional Settings Example 2 If the SEL-751A Relay is used on a feeder with a line-side independent power producer (cogenerator), the utility should not reclose into a line still energized by an islanded generator. To monitor line voltage...
  • Page 163 When reset timing starts again, the reset timer is fully loaded. Thus, successful reset timing has to be continuous. Use the RSTMN Relay Word bit to monitor reset timing (see Monitoring Open Interval and Reset Timing on page 4.65). Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 164 This assertion/deassertion indicates that a downstream device (e.g., line recloser—see Figure 4.37) has operated to clear a fault. Incrementing the shot counter keeps the SEL-751A “in step” with the downstream device, as is shown in Additional Settings Example 1 on page 4.73 Additional Settings Example 2 on page 4.74.
  • Page 165 Fast Curve (Line Recloser) 51P1 Figure 4.37 Sequence Coordination Between the SEL-751A and a Line Recloser Assume that the line recloser is set to operate twice on the fast curve and then twice on the slow curve. The slow curve is allowed to operate after two fast curve operations because the fast curves are then inoperative for tripping.
  • Page 166 Figure 4.38 Operation of SEL-751A Shot Counter for Sequence Coordination With Line Recloser (Additional Settings Example 1) If the SEL-751A is in the Reset State (79RS = logical 1) and then a permanent fault beyond the line recloser occurs (fault current I Figure 4.37), the line recloser fast curve operates to clear the fault.
  • Page 167 Refer to Figure 4.39. If the SEL-751A is in the Reset State (79RS = logical 0) with the shot counter reset (shot = 0; SH0 = logical 1) and then a permanent fault beyond the line recloser occurs (fault current I Figure 4.37), the...

  • Page 168: Demand Metering

    79SEQ := 79RS AND 51P1P AND (logical 0) = Logical 0 The shot counter stays at shot = 1. Thus, if there is a coincident fault between the SEL-751A and the line recloser, the SEL-751A will operate on 51AT, 51BT, or 51CT and then reclose once, instead of going straight to the Lockout State (shot = 1 <...
  • Page 169 Should the relay lose control power, it will restore the peak demand values saved by the relay. Demand metering peak recording is momentarily suspended when SEL OGIC control equation setting FAULT is asserted (= logical 1). The differences between thermal and rolling demand metering are explained in the following discussion.
  • Page 170 Time (Minutes) DMTC = 15 minutes Rolling Demand Meter Response (EDEM = ROL) Time (Minutes) Figure 4.41 Response of Thermal and Rolling Demand Meters to a Step Input (Setting DMTC = 15 minutes) SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 171 (1.0 per unit) after a time period equal to setting DMTC = 15 minutes, referenced to when the step current input is first applied. The SEL-751A updates thermal demand values approximately every second. Rolling Demand Meter Response The response of the rolling demand meter in Figure 4.41...
  • Page 172 –5 to 0 minutes 1.0 per unit 0 to 5 minutes 1.0 per unit 5 to 10 minutes 2.0 per unit Rolling demand meter response at “Time = 10 minutes” = 2.0/3 = 0.67 per unit. SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 173: Logic Settings (Set L Command)

    Latch control switches (latch bits are the outputs of these switches) replace traditional latching devices. Traditional latching devices maintain output contact state. The SEL-751A latch control switch also retains state even when power to the device is lost. If the latch control switch is set to a programmable...
  • Page 174 RSTn asserts to logical 1, latch bit LTn deasserts to logical 0. If both settings SETn and RSTn assert to logical 1, setting RSTn has priority and latch bit LTn deasserts to logical 0. You can use these latch bits in SEL control OGIC equations to create custom logic for your application.
  • Page 175 LT01 through LT32) are retained, as in the preceding Power Loss on page 4.83 explanation. If the individual settings change causes a change in SEL OGIC control equation settings SETn or RSTn (n = 1 through 32), the retained states of the latch bits can be changed, subject to the newly enabled settings SETn or RSTn.
  • Page 176 +16777215.99. Comments can be added to both boolean and math SEL control equations OGIC by inserting a # symbol. Everything following the # symbol in a SEL OGIC control equation is treated as a comment. See Table 4.34 for this and other Boolean and math operators and values.
  • Page 177 <> Boolean Boolean (lowest prece- dence) Parentheses Operator ( ) You can use more than one set of parentheses in a SEL control equation OGIC setting. For example, the following Boolean SEL control equation setting OGIC has two sets of parentheses:...
  • Page 178 Relay Word bit asserts (going from logical 0 to logical 1), R_TRIG interprets this logical 0 to logical 1 transition as a “rising edge” and asserts to logical 1 for one processing interval. For example, the Boolean SEL control equation event report generation OGIC...
  • Page 179 (“\” is entered only at the Mathematical end of a line) Timers Reset When If the device loses power or settings change, the SEL control equation OGIC variables/timers reset. Relay Word bits SVn and SVnT (n = 01–32) reset to Power Lost or logical 0 after power restoration or a settings change.
  • Page 180 SV/Timers Settings The SEL-751A includes 32 SEL variables. Table 4.35 shows the pickup, OGIC dropout, and equation settings for SV01 and SV02. The remaining SEL OGIC variables have the same default settings as SV02. Table 4.35 SEL Variable Settings OGIC...
  • Page 181 (SCn = 0, n = 01 to 32). SCnn Output Value This counter output is an analog value that may be used with analog comparison operators in a SEL OGIC control equation and viewed using the COU com- mand.
  • Page 182 0 (SCnn := 0), causing Relay Word bit SCnnQD to assert (SCnnQD := logical 1), and Relay Word bit SCnnQU to deassert (SCnnQU := logical 0). SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 183 • • • • • The SEL-751A provides the ability to use SEL control equations to map OGIC protection (trip and warning) and general-purpose control elements to the outputs. In addition, you can enable fail-safe output contact operation for relay contacts on an individual basis.

  • Page 184: Global Settings (Set G Command)

    OGIC minimum metering, energy metering, and demand metering. Event Messenger The SEL-751A can be configured to automatically send ASCII message on a communications port when trigger condition is satisfied. Use the SET P Points command to set PROTO := EVMSG on the desired port to select the port. This feature is designed to send messages to the SEL-3010 Event Messenger, however, any device capable of receiving ASCII messages can be used.
  • Page 185 Formatted message out when triggered: THE LOAD CURRENT IS 157.44 AMPERES MPTX01 := THE LOAD CURRENT IS %d AMPERES MPAQ01 value = 157.44 Formatted message out when triggered: THE LOAD CURRENT IS 157 AMPERES Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 186: Synchrophasor Measurement

    Group 1, 2, and 3 are active. With the settings shown above, SS1 is set equal to logical 1, thus setting Group 1 always is active. Synchrophasor Measurement The SEL-751A relay provides Phasor Measurement Control Unit (PMCU) capabilities when connected to an IRIG-B time source. See Appendix H:...

  • Page 187: Arc-Flash Protection

    0.02 • I Figure 4.51 Breaker Failure Logic Arc-Flash Protection The SEL-751A offers advanced arc-flash protection capability aimed at minimizing the hazards associated with high energy arc (faults) in metal- enclosed and metal-clad switchgear. The system supports four fiber-optic light sensors capable of detecting the high energy arc-flash events and tripping the breaker within milliseconds of the fault.
  • Page 188 50PAF Element Shown, 50NAF Element is Similar Figure 4.52 Arc-Flash Instantaneous Overcurrent Element Logic Arc-Flash Time- The SEL-751A relay offers four fiber-optic light sensor inputs. Each input is associated with one inverse time-over light element offering enhanced security Overlight Elements coupled with exceptionally fast operation.
  • Page 189 Setting range with point sensor. Setting range with fiber sensor. The default processing interval in the SEL-751A is ¼ of the power system cycle. However, to obtain a faster arc-flash protection you can select two outputs that will be processed every 1/16 of a power system cycle. Use the setting AOUTSLOT to select these outputs.
  • Page 190 AND of the 50PAF and TOLn outputs. In applications where intermittent loss of load can be tolerated (non critical loads), it may be desirable to operate without overcurrent element supervision (OUTxxx := TOLn), relying only on the light detection element instead of SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 191 TOL2 OR TOL3) EXAMPLE 4.24 Output Logic Programming Example 2: SEL-751A applied at the radial feeder breaker. Assume light sensors LS1 and LS2 are located downstream, LS3 is located upstream of the feeder breaker, and output contacts in slot 3 are selected for the high speed processing (AOUTSLOT := 301_2).

  • Page 192: Analog Inputs

    ±1 uA or ±1 mV. Signal offset compensation factor calculation procedure: Step 1. Turn the SEL-751A on and allow it to warm up for a few minutes. Step 2. Set the analog inputs for each analog channel to the desired range using the AIxxxTYP, AIxxxL, AIxxxH, AIxxxEL, and AIxxxEH settings (for example, ±1 mA).
  • Page 193 AI301NAM:= AI301 ? Use the Instrument Tag Name to give the analog quantity a more descriptive name. This tag name appears in reports (EVENT, METER, and SUMMARY) instead of the default name of AI301. SEL control equations, Signal OGIC Profiles, and Fast Message Read use the default names. Use up to eight valid tag name characters to name the analog quantity.
  • Page 194 Although the device accepts alphanumeric characters, the name AI301NAM setting must begin with an alpha character (A–Z) and not a number. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 195 Voltage setting range for a voltage transducer, i.e., when AI301TYP := V Analog Outputs If an SEL-751A configuration includes the four analog inputs and four analog outputs (4 AI/4 AO) card, the analog outputs are allocated to output numbers 1-4.

  • Page 196: Analog Outputs

    Figure 4.58 Analog Output Settings Station DC Battery Monitor The station dc battery monitor in the SEL-751A can alarm for under- or overvoltage dc battery conditions and give a view of how much the station dc battery voltage dips when tripping, closing, and other dc control functions take place.

  • Page 197: Breaker Monitor

    Protection and Logic Functions 4.105 Breaker Monitor Breaker Monitor The breaker monitor in the SEL-751A helps in scheduling circuit breaker maintenance. Refer to Breaker Monitor on page 5.15 for a detailed description Table 5.10 for settings. Digital Input Debounce To comply with different control voltages, the SEL-751A offers dc debounce as well as ac debounce modes.
  • Page 198 0. Table 4.49 shows the settings prompt, setting range, and factory default settings for a card in Slot C. See the SEL-751A Settings Sheets for a complete list of input debounce settings. Table 4.49 Slot C Input Debounce Settings...

  • Page 199: Data Reset

    DISABLE SETTINGS DSABLSET := 0 OGIC Time Synchronization Source The SEL-751A accepts a demodulated IRIG-B time signal. Table 4.51 shows the setting to identify the input for the signal. Set TIME_SRC := IRIG1 when you use relay terminals B01/B02 or EIA-232 serial Port 3 for the time signal input.

  • Page 200: Time Synchronization Source

    IRIG TIME SOURCE IRIG1, IRIG2 TIME_SRC := IRIG1 Port Settings (SET P Command) The SEL-751A provides settings that allow you to configure the parameters for the communications ports. See Section 2: Installation for a detailed description of port connections. On the base unit: Port F (front panel) is an EIA-232 port;...
  • Page 201 PORT 2 Table 4.54 Fiber-Optic Serial Port Settings Setting Name := Setting Prompt Setting Range Factory Default PROTOCOL SEL, DNP, MOD, PROTO := SEL EVMSG, PMU, MBA, NOTE: For additional settings when MBB, MB8A, MB8B, PROTO := MBxx, see Table I.5...
  • Page 202 PORT 3 Table 4.55 Rear-Panel Serial Port (EIA-232) Settings Setting Name := Setting Prompt Setting Range Factory Default PROTOCOL SEL, DNP, MOD, PROTO := SEL EVMSG, PMU, MBA, NOTE: For additional settings when MBB, MB8A, MB8B, PROTO := MBxx, see Table I.5...
  • Page 203 Protection and Logic Functions 4.111 Front-Panel Settings (SET F Command) Set PROTO := SEL (standard SEL ASCII protocol), MOD (Modbus RTU protocol), or one of the M protocols, as needed for your IRRORED application. For detailed information, refer to Appendix C: SEL...

  • Page 204: Front-Panel Settings (Set F Command)

    Name as valid, a display point with an empty Name setting is always hidden (see below). Commas are significant in identifying and separating the four strings. Use quotation marks only if the SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 205 After connecting a form a (normally open) auxiliary contact from the HV circuit breaker to Input IN101 and a similar contact from the LV circuit breaker to Input IN102 of the SEL-751A, we are ready to program the display points, using the following information for the HV breaker (LV breaker similar): ➤...
  • Page 206 Clear String (TRFR 1 HV BRKR). When both breakers are closed, the relay has the set state information for both HV and LV breakers, and the relay displays the information as shown in Figure 4.65. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 207 Figure 4.68 Front-Panel Display for a Binary Entry in the Name String Only Analog Display Point Entry Composition In general, the legal syntax for analog display points consists of the following two fields or strings: Name, “User Text and Formatting.” Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 208 DP02 := TID, “{16}” ? AI301,TEMPERATURE: <Enter> Table 4.64 Entry in the Name String and the Alias Strings Name Alias Set String Clear String IN101 INPUT IN101 — — AI301 TEMPERATURE — — SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 209 To measure these temperatures, we have installed an analog card in relay Slot C, and connected 4–20 mA transducers inputs to analog inputs AI301 (hot-spot temperature), AI302 (oil temperature), and AI303 (winding temperature). Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 210 TRFR 1 HV BRKR:= Screen 1 TRFR 1 LV BRKR:= Figure 4.73 Rotating Display To change the temperature units to more descriptive engineering units, enter the desired units with the AIxxxEU (e.g., AI302EU) setting. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 211 Local bit 2 starts a fan motor (START) that only needs a short pulse to seal itself in, and we use the clear/pulse combination. Figure 4.74 shows the settings to program the two local bits. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 212 Save changes (Y,N)? Y <Enter> Settings Saved =>> Figure 4.74 Adding Two Local Bits Target LED Settings The SEL-751A offers the following two types of LEDs. See Figure 8.1 Figure 8.26 for the programmable LED locations: ➤ Six Target LEDs ➤...
  • Page 213 AND NOT TRGTR Pushbutton LEDs Enter any of the Relay Word bits (or combinations of Relay Word bits) as conditions in the PBp_LED (p = 1A, 1B, . . . 4A, 4B) SEL control OGIC equation settings. When these Relay Word bits assert, the corresponding LED also asserts.

  • Page 214: Report Settings (Set R Command)

    SER settings. Any auto-deletion notice entry will be lost during changes of settings. The deleted items can be viewed in the SER Delete Report (command SER D—refer to Section 7: Communications for additional information). SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 215 Setting Prompt Alias Word Bit Text Text ALIAS1 := PB01 FP_AUX1 PICKUP DROPOUT ALIAS2 := PB02 FP_LOCK PICKUP DROPOUT ALIAS3 := PB03 FP_CLOSE PICKUP DROPOUT ALIAS4 := PB04 FP_TRIP PICKUP DROPOUT ALIAS5 –ALIAS20 Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 216: Dnp Map Settings (Set Dnp N Command, N = 1, 2, Or 3)

    DNP Binary Input Label Name 10 characters BI_02 := TLED_01 DNP Binary Input Label Name 10 characters BI_03 := TLED_02 · · · DNP Binary Input Label Name 10 characters BI_99 := NA SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 217: Modbus Map Settings (Set M Command)

    MOD_001 := • • • • • • • • • USER REG#125 NA, 1 Modbus Register Label MOD_125 := Appendix E: Modbus RTU Communications for Modbus Register Labels and factory default settings. Date Code 20100129 Instruction Manual SEL-751A Relay...
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  • Page 219: Station Dc Battery Monitor

    (selected from the Analog Quantities) every 5, 10, 15, 30, or 60 minutes. The data are stored in nonvolatile memory. As many as 4000 time samples are stored. Station DC Battery Monitor is available as an option in the SEL-751A relay. Refer to Station DC Battery Monitor on page 5.11 for description and application details.

  • Page 220: Power Measurement Conventions

    Metering and Monitoring Power Measurement Conventions Power Measurement Conventions The SEL-751A uses the IEEE convention for power measurement. The implications of this convention are depicted in Figure 5.1. Source I lags V I lags V Direction of Q+ (VAR) W = –...
  • Page 221 Metering and Monitoring Metering Fundamental Table 5.1 details each of the fundamental meter data types in the SEL-751A. Section 8: Front-Panel Operations Section 7: Communications describe Metering how to access the various types of meter data using the relay front panel and communications ports.
  • Page 222 RTDs if any have failed (see Table 5.3 for details). Table 5.2 Thermal Meter Values Relay Option Thermal Values With External SEL-2600 RTD Module or All RTD Temperatures Internal RTD Option SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 223 Figure 5.3 METER T Command Report With RTDs Energy Metering The SEL-751A with the voltage option includes energy metering. Use this form of metering to quantify real, reactive, and apparent energy supplied to the feeder load. Below are the energy meter values.
  • Page 224 Maximum and minimum real, reactive and apparent 3-phase power (kW, kVAR, kVA) With RTD option or Maximum and minimum RTD temperatures (°C) SEL-2600 RTD Module With analog input option Maximum and minimum analog input values (engineering units) All maximum and minimum metering values will have the date and time that they occurred.
  • Page 225 Math Variable The SEL-751A includes 32 math variables. When you receive your SEL-751A, no math variables are enabled. To use math variables, enable the Metering number of math variables (between 1 and 32) you require, using the EMV setting in the Logic setting category.
  • Page 226 =>> Figure 5.9 Device Response to the METER RMS Command Analog Input The SEL-751A can monitor analog (transducer) quantities that it is measuring if equipped with optional analog inputs. Analog input metering shows Metering transducer values from standard voltage and current transducers. These values can then be used for automation and control applications within an industrial plant or application.
  • Page 227 Metering and Monitoring Metering Arc-Flash Light When the SEL-751A is ordered with the arc-flash detection (AFD) option (order the 3 AVI / 4 AFDI card for slot E), the relay provides light metering Intensity Metering data with the METER LIGHT (METER L command) report. The light inputs LS1–LS4 are given in percent of full scale.
  • Page 228 NOTE: In order to have the MET PM The METER PM command will only operate when the SEL-751A is in the xx:yy:zz response transmitted from a IRIG timekeeping mode, as indicated by Relay Word bit TSOK = logical 1.

  • Page 229: Load Profiling

    Figure 5.14 Device Response to the LDP Command Station DC Battery Monitor The station dc battery monitor in the SEL-751A can alarm for under- or overvoltage dc battery conditions and give a view of how much the station dc battery voltage dips when tripping, closing, and other dc control functions take place.
  • Page 230 This range allows the SEL-751A to monitor nominal battery voltages of 24, 48, 110, 125, 220, and 250V. When testing the pickup settings DCLOP and DCHIP, do not operate the SEL-751A outside of its power supply limits. See Specifications: General on page 1.20 for the various power supply specifications.
  • Page 231 SVn = DCLO * DCHI DCLOP SVnPU DCLO * DCHI SVnT SVnDO DCHIP OUTxxx = SVnT Figure 5.16 Create DC Voltage Elements With SEL Control Equations OGIC DCLO < DCHI (Top of Figure 5.16) Output contact OUTxxx asserts when: ≤ DCLOP or V ≥...
  • Page 232 Vdc in the event report. To generate an event report for external trips, program an optoisolated input INxyz (monitoring the trip bus) in the SEL control equation event report OGIC generation setting: ER = R_TRIG(INxyz) OR…...
  • Page 233 Metering and Monitoring 5.15 Breaker Monitor Station DC Battery Voltage Dips During Circuit Breaker Closing To generate an event report when the SEL-751A closes the circuit breaker, make the SEL control equation event report generation setting: OGIC ER = R_TRIG(OUT102) OR…...
  • Page 234 The action of a circuit breaker closing and then later opening is counted as one close/open operation. Connect the plotted points in Figure 5.17 for a breaker maintenance curve. To estimate this breaker maintenance curve in the SEL-751A breaker monitor, three set points are entered: Set Point 1 maximum number of close/open operations with COSP1 corresponding current interruption level.
  • Page 235 COSP3 = 12 KASP1 = 1.20 KASP2 = 8.00 KASP3 = 20.00 10,000 1000 6 7 8 9 kA Interrupted per Operation Figure 5.17 Plotted Breaker Maintenance Points for a 25 kV Circuit Breaker Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 236 COSP3 = 12 6 7 8 9 kA Interrupted per Operation Figure 5.18 SEL-751A Breaker Maintenance Curve for a 25 kV Circuit Breaker In this example, set point KASP2, COSP2 happens to be from an in-between breaker maintenance point in the breaker maintenance information in Table 5.9...
  • Page 237 The acquired current values are then applied to the breaker maintenance curve and the breaker monitor accumulated currents/trips (see references in previous paragraph). In the factory default settings, the SEL control equation breaker monitor OGIC...
  • Page 238 10 percent curve has only 1/10 of the close/open operations of the 100 percent curve. 100% 10,000 1000 6 7 8 9 kA Interrupted per Operation Figure 5.20 Breaker Monitor Accumulates 10 Percent Wear SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 239 25 percent curve has only 1/4 of the close/open operations of the 100 percent curve. 100% 10,000 1000 6 7 8 9 kA Interrupted per Operation Figure 5.21 Breaker Monitor Accumulates 25 Percent Wear Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 240 50 percent curve has only 1/2 of the close/open operations of the 100 percent curve. 100% 10,000 1000 6 7 8 9 kA Interrupted per Operation Figure 5.22 Breaker Monitor Accumulates 50 Percent Wear SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 241 BRE R command. Additionally, logic outputs assert for alarm or other control applications—see the following discussion. 100% 10,000 1000 6 7 8 9 kA Interrupted per Operation Figure 5.23 Breaker Monitor Accumulates 100 Percent Wear Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 242 Relay Word bit BCWA to deassert (BCWA = logical 0). Via Front Panel The information and reset functions available via the previously discussed serial port commands BRE and BRE R are also available via the front-panel. Section 8: Front-Panel Operations for details. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 243 Relay initiated trips (Rly Trips) are also referred to as internally initiated trips (Int Trips) in the course of this manual; the terms are interchangeable. EXAMPLE 5.2 Factory Default Setting Example As discussed previously, the SEL control equation breaker OGIC...
  • Page 244 OGIC set: BKMON = INxxx then the SEL-751A breaker monitor sees all trips. If output contact OUT101 asserts, energizing the trip bus, the breaker monitor will deem it a relay initiated trip. This is because when BKMON is newly asserted (input INxxx energized), the TRIP Relay Word bit is asserted.
  • Page 245 Section 6 Settings Overview The SEL-751A Feeder Protection Relay stores the settings you enter in nonvolatile memory. Settings are divided into the following eight setting classes: 1. Relay Group n (where n = 1, 2, or 3) 2. Logic Group n (where n = 1, 2, or 3) 3.

  • Page 246: View/Change Settings With Front Panel

    {ESC} pushbutton until the following changing the RELAY message appears: Save Changes? NOTE: Each SEL-751A is shipped with default factory settings. Select and enter the appropriate command by pushing the {ENT} pushbutton. Calculate the settings for your application to ensure secure and Select to save the settings changes and to discard the changes.
  • Page 247 Config Settings Max Ph Overcurr • Demand Mtr Set Freq Settings Trip/Close Logic Config Menu CTRN 120.00 • • • SINGLEV PTR Setting PHASE PT RATIO PTR=00120.00 Figure 6.1 Front-Panel Setting Entry Example Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 248: View/Change Settings Over Communications Port

    You may append a setting name to each of the commands to specify the first setting to display (e.g., SET 50P1P displays the relay settings starting with setting 50P1P). The default is the first setting. SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 249: Setting Entry Error Messages

    Saves Settings? before the settings are stored. If any of these checks fail, the relay issues a self-explanatory error message, and returns you to the settings list for a correction. Date Code 20100129 Instruction Manual SEL-751A Relay...
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  • Page 251 See Section 4: Protection and Logic Functions detailed descriptions of the settings. ➤ Some settings require an optional module. (Refer to SEL-751A Model Option Table, Table 1.1, and notes with the settings below for details.) ➤...
  • Page 252 50P3P 0.10–20.00 A {1 A nom.}) MAXP OC TRIP DLY (0.00–5.00 sec) 50P3D (Hidden if 50P3P := OFF) MAXP OC TRQ CON (SEL 50P3TC (Hidden if 50P3P := OFF) OGIC MAXP OC TRIP LVL (OFF, 0.50–100.00 A {5 A nom.}, 50P4P 0.10–20.00 A {1 A nom.})
  • Page 253 TOC TRIP LVL (OFF, 0.50–16.00 A {5 A nom.}, 51AP 0.10–3.20 A {1 A nom.}) TOC CURVE SEL (U1, U2, U3, U4, U5, C1, C2, C3, C4, C5) 51AC (Hidden if 51AP := OFF) TOC TIME DIAL (0.50–15.00 {if 51_C := U_}, 0.05–1.00 {if...
  • Page 254 SET.4 SEL-751A Settings Sheets Date________________ of 68 Group Settings (SET Command) TOC CURVE SEL (U1, U2, U3, U4, U5, C1, C2, C3, C4, C5) 51BC (Hidden if 51BP := OFF) TOC TIME DIAL (0.50–15.00 {if 51_C := U_}, 51BTD 0.05–1.00 {if 51_C := C_})
  • Page 255 TOC TRIP LVL (OFF, 0.50–16.00 A {5 A nom.}, 0.10–3.20 A 51QP {1 A nom.}) TOC CURVE SEL (U1, U2, U3, U4, U5, C1, C2, C3, C4, C5) 51QC (Hidden if 51QP := OFF) TOC TIME DIAL (0.50–15.00 {if 51_C := U_}, 0.05–1.00 {if...
  • Page 256 TOC TRIP LVL (OFF, 0.50–16.00 A {5 A nom.}, 0.10–3.20 A 51G1P {1 A nom.}) TOC CURVE SEL (U1, U2, U3, U4, U5, C1, C2, C3, C4, C5) 51G1C (Hidden if 51G1P := OFF) TOC TIME DIAL (0.50–15.00 {if 51_C := U_}, 0.05–1.00 {if...
  • Page 257 Date _______________ SEL-751A Settings Sheets SET.7 Group Settings (SET Command) of 68 RTD3 LOCATION (OFF, WDG, BRG, AMB, OTH) RTD3LOC := RTD3 TYPE (PT100, NI100, NI120, CU10) RTD3TY (Hidden if RTD3LOC := OFF) RTD3 TRIP LEVEL (OFF, 1–250 degC) TRTMP3 (Hidden if RTD3LOC := OFF) RTD3 WARN LEVEL (OFF, 1–250 degC)
  • Page 258 SET.8 SEL-751A Settings Sheets Date________________ of 68 Group Settings (SET Command) RTD9 TYPE (PT100, NI100, NI120, CU10) RTD9TY (Hidden if RTD9LOC := OFF) RTD9 TRIP LEVEL (OFF, 1–250 degC) TRTMP9 (Hidden if RTD9LOC := OFF) RTD9 WARN LEVEL (OFF, 1–250 degC)
  • Page 259 Date _______________ SEL-751A Settings Sheets SET.9 Group Settings (SET Command) of 68 UVS LEVEL 2 (OFF, 2.00–300.00 V) 27S2P UVS DELAY 2 (0.0–120.0 sec) 27S2D (Hidden if 27S2P := OFF) Overvoltage (All or some of the settings below are hidden if appropriate Voltage Card Option not...
  • Page 260 SET.10 SEL-751A Settings Sheets Date________________ of 68 Group Settings (SET Command) SYNCPH PHASE SYNCPH (VAB, VBC, VCA, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330 deg lag VAB) (Hidden if E25 := N) (Hidden if DELTA_Y := WYE) BRKR CLOSE TIME (OFF, 1–1000 ms)
  • Page 261 Date _______________ SEL-751A Settings Sheets SET.11 Group Settings (SET Command) of 68 Rate-of-Change of Frequency (Hidden if Voltage Card Option Is Not xx73xx or xx74xx, see Table 1.1) ENABLE 81R (OFF,1–4) (All Rate of Change of Frequency E81R settings below Hidden if E81R := NONE 81R VOLTAGE SUP (OFF,0.1–1.3 xVnm)
  • Page 262 SET.12 SEL-751A Settings Sheets Date________________ of 68 Group Settings (SET Command) Power (Hidden if Voltage Card Option Is Not xx73xx or xx74xx, see Table 1.1) ENABLE PWR ELEM (N, 3P1, 3P2) EPWR (All Power element settings below hidden if EPWR := N) 3PH PWR ELEM PU (OFF, 0.2–1300.00 VA {1 A phase CTs},...
  • Page 263 Date _______________ SEL-751A Settings Sheets SET.13 Logic Settings (SET L Command) of 68 RCLS INIT SUPVSN (SEL 79RIS OGIC DRIVE-TO-LOCKOUT (SEL 79DTL OGIC DRIVE-TO-LSTSHOT (SEL 79DLS OGIC SKIP SHOT (SEL 79SKP OGIC STALL OPN INTRVL (SEL 79STL OGIC BLOCK RESET TMNG (SEL...
  • Page 264 SET.14 SEL-751A Settings Sheets Date________________ of 68 Logic Settings (SET L Command) RST10 SET11 RST11 SET12 RST12 SET13 RST13 SET14 RST14 SET15 RST15 SET16 RST16 SET17 RST17 SET18 RST18 SET19 RST19 SET20 RST20 SET21 RST21 SET22 RST22 SET23 RST23 SET24...
  • Page 265 Date _______________ SEL-751A Settings Sheets SET.15 Logic Settings (SET L Command) of 68 RST29 SET30 RST30 SET31 RST31 SET32 RST32 SV/Timers SV TIMER PICKUP (0.00–3000.00 sec) SV01PU SV TIMER DROPOUT (0.00–3000.00 sec) SV01DO SV INPUT (SEL SV01 OGIC SV TIMER PICKUP (0.00–3000.00 sec) SV02PU SV TIMER DROPOUT (0.00–3000.00 sec)
  • Page 266 SET.16 SEL-751A Settings Sheets Date________________ of 68 Logic Settings (SET L Command) SV INPUT (SEL SV09 OGIC SV TIMER PICKUP (0.00–3000.00 sec) SV10PU SV TIMER DROPOUT (0.00–3000.00 sec) SV10DO SV INPUT (SEL SV10 OGIC SV TIMER PICKUP (0.00–3000.00 sec) SV11PU SV TIMER DROPOUT (0.00–3000.00 sec)
  • Page 267 Date _______________ SEL-751A Settings Sheets SET.17 Logic Settings (SET L Command) of 68 SV TIMER PICKUP (0.00–3000.00 sec) SV21PU SV TIMER DROPOUT (0.00–3000.00 sec) SV21DO SV INPUT (SEL SV21 OGIC SV TIMER PICKUP (0.00–3000.00 sec) SV22PU SV TIMER DROPOUT (0.00–3000.00 sec)
  • Page 268 SV INPUT (SEL SV32 OGIC Counters Equations SC PRESET VALUE (1–65000) SC01PV SC RESET INPUT (SEL SC01R OGIC SC LOAD PV INPUT (SEL SC01LD OGIC SC CNT UP INPUT (SEL SC01CU OGIC SC CNT DN INPUT (SEL SC01CD OGIC SC PRESET VALUE (1–65000)
  • Page 269 SET.19 Logic Settings (SET L Command) of 68 SC PRESET VALUE (1–65000) SC07PV SC RESET INPUT (SEL SC07R OGIC SC LOAD PV INPUT (SEL SC07LD OGIC SC CNT UP INPUT (SEL SC07CU OGIC SC CNT DN INPUT (SEL SC07CD OGIC SC PRESET VALUE (1–65000)
  • Page 270 SET.20 SEL-751A Settings Sheets Date________________ of 68 Logic Settings (SET L Command) SC CNT DN INPUT (SEL SC13CD OGIC SC PRESET VALUE (1–65000) SC14PV SC RESET INPUT (SEL SC14R OGIC SC LOAD PV INPUT (SEL SC14LD OGIC SC CNT UP INPUT (SEL...
  • Page 271 Date _______________ SEL-751A Settings Sheets SET.21 Logic Settings (SET L Command) of 68 SC CNT UP INPUT (SEL SC20CU OGIC SC CNT DN INPUT (SEL SC20CD OGIC SC PRESET VALUE (1–65000) SC21PV SC RESET INPUT (SEL SC21R OGIC SC LOAD PV INPUT (SEL...
  • Page 272 SET.22 SEL-751A Settings Sheets Date________________ of 68 Logic Settings (SET L Command) SC LOAD PV INPUT (SEL SC27LD OGIC SC CNT UP INPUT (SEL SC27CU OGIC SC CNT DN INPUT (SEL SC27CD OGIC SC PRESET VALUE (1–65000) SC28PV SC RESET INPUT (SEL...
  • Page 273 Date _______________ SEL-751A Settings Sheets SET.23 Logic Settings (SET L Command) of 68 MV06 MV07 MV08 MV09 MV10 MV11 MV12 MV13 MV14 MV15 MV16 MV17 MV18 MV19 MV20 MV21 MV22 MV23 MV24 MV25 MV26 MV27 MV28 MV29 MV30 MV31 MV32...
  • Page 274 SET.24 SEL-751A Settings Sheets Date________________ of 68 Logic Settings (SET L Command) Slot C Output (Hidden If Output Option Not Included) OUT301 FAIL-SAFE (Y, N) OUT301FS := OUT301 OUT302 FAIL-SAFE (Y, N) OUT302FS := OUT302 OUT303 FAIL-SAFE (Y, N) OUT303FS :=...
  • Page 275 Date _______________ SEL-751A Settings Sheets SET.25 Global Settings (SET G Command) of 68 TMB4A TMB5A TMB6A TMB7A TMB8A TMB1B TMB2B TMB3B TMB4B TMB5B TMB6B TMB7B TMB8B Global Settings (SET G Command) General PHASE ROTATION (ABC, ACB) PHROT RATED FREQ. (50, 60 Hz)
  • Page 276 SET.26 SEL-751A Settings Sheets Date________________ of 68 Global Settings (SET G Command) MESSENGER POINT MP05 TRIGGER ( MPTR05 Off, 1 Relay Word bit MESSENGER POINT MP05 AQ ( MPAQ05 None, 1 analog quantity MESSENGER POINT MP05 TEXT ( MPTX05 148 characters...
  • Page 277 Date _______________ SEL-751A Settings Sheets SET.27 Global Settings (SET G Command) of 68 MESSENGER POINT MP16 AQ ( MPAQ16 None, 1 analog quantity MESSENGER POINT MP16 TEXT ( MPTX16 148 characters MESSENGER POINT MP17 TRIGGER ( MPTR17 Off, 1 Relay Word bit...
  • Page 278 SET.28 SEL-751A Settings Sheets Date________________ of 68 Global Settings (SET G Command) MESSENGER POINT MP27 TEXT ( MPTX27 148 characters MESSENGER POINT MP28 TRIGGER ( MPTR28 Off, 1 Relay Word bit MESSENGER POINT MP28 AQ ( MPAQ28 None, 1 analog quantity...
  • Page 279 Date _______________ SEL-751A Settings Sheets SET.29 Global Settings (SET G Command) of 68 TRIG REASON BIT 1 (SEL TREA1 OGIC TRIG REASON BIT 2 (SEL TREA2 OGIC TRIG REASON BIT 3 (SEL TREA3 OGIC TRIG REASON BIT 4 (SEL TREA4...
  • Page 280 SET.30 SEL-751A Settings Sheets Date________________ of 68 Global Settings (SET G Command) If AIx01TYP = I AIx01 LOW IN VAL (–20.480 to +20.480; mA) AIx01L AIx01 HI IN VAL (–20.480 to +20.480; mA) AIx01H If AIx01TYP = V AIx01 LOW IN VAL (–10.240 to +10.240 V) AIx01L AIx01 HI IN VAL (–10.240 to +10.240 V)
  • Page 281 Date _______________ SEL-751A Settings Sheets SET.31 Global Settings (SET G Command) of 68 AIx03 TAG NAME (8 characters 0–9, A–Z, _) AIx03NAM := AIx03 TYPE (I, V) AIx03TYP := If AIx03TYP = I AIx03 LOW IN VAL (–20.480 to +20.480; mA) AIx03L AIx03 HI IN VAL (–20.480 to +20.480;...
  • Page 282 SET.32 SEL-751A Settings Sheets Date________________ of 68 Global Settings (SET G Command) AIx04 HI ALARM (OFF, –99999.000 to +99999.000) AIx04HAL := AIx05 TAG NAME (8 characters 0–9, A–Z, _) AIx05NAM := AIx05 TYPE (I, V) AIx05TYP := If AIx05TYP = I AIx05 LOW IN VAL (–20.480 to +20.480;...
  • Page 283 Date _______________ SEL-751A Settings Sheets SET.33 Global Settings (SET G Command) of 68 AIx06 HI WARN L1 (OFF, –99999.000 to +99999.000) AIx06HW1 := AIx06 HI WARN L2 (OFF, –99999.000 to +99999.000) AIx06HW2 := AIx06 HI ALARM (OFF, –99999.000 to +99999.000) AIx06HAL := AIx07 TAG NAME (8 characters 0–9, A–Z, _)
  • Page 284 SET.34 SEL-751A Settings Sheets Date________________ of 68 Global Settings (SET G Command) AIx08 LO WARN L2 (OFF, –99999.000 to +99999.000) AIx08LW2 := AIx08 LO ALARM (OFF, –99999.000 to +99999.000) AIx08LAL := AIx08 HI WARN L1 (OFF, –99999.000 to +99999.000) AIx08HW1 := AIx08 HI WARN L2 (OFF, –99999.000 to +99999.000)
  • Page 285 Date _______________ SEL-751A Settings Sheets SET.35 Global Settings (SET G Command) of 68 AOx03 HI OUT VAL (–20.480 to +20.480 mA) AOx03H If AOx03TYP = V AOx03 LO OUT VAL (–10.240 to +10.240 V) AOx03L AOx03 HI OUT VAL (–10.240 to +10.240 V)
  • Page 286 SET.36 SEL-751A Settings Sheets Date________________ of 68 Global Settings (SET G Command) Input Debounce Settings (Slot D) (Hidden If Input Option Not Included) IN401 Debounce (AC, 0–65000 ms) IN401D IN402 Debounce (AC, 0–65000 ms) IN402D IN403 Debounce (AC, 0–65000 ms) IN403D IN404 Debounce (AC, 0–65000 ms)
  • Page 287 (Hidden if Fiber-Optic Port 2 Not Available) IRIG TIME SOURCE (IRIG1, IRIG2) TIME_SRC := SET PORT p (p = F, 1, 2, 3, or 4) Command PORT F PROTOCOL (SEL, MOD, EVMSG, PMU) PROTO Communications SPEED (300, 1200, 2400, 4800, 9600, 19200, 38400 bps) SPEED...
  • Page 288 SET.38 SEL-751A Settings Sheets Date________________ of 68 SET PORT p (p = F, 1, 2, 3, or 4) Command TCP Keep-Alive Interval Range (1–20 sec) KAINTV Hidden if ETCPKA := N TCP Keep-Alive Count Range (1–20) ( KACNT Hidden if ETCPKA := N...
  • Page 289 Date _______________ SEL-751A Settings Sheets SET.39 SET PORT p (p = F, 1, 2, 3, or 4) Command of 68 Analog Input Default Variation (1–6) DVARAI1 := Class for Binary Event Data (0–3) ECLASSB1 := Class for Counter Event Data (0–3) ECLASSC1 := Class for Analog Event Data (0–3)
  • Page 290 SET.40 SEL-751A Settings Sheets Date________________ of 68 SET PORT p (p = F, 1, 2, 3, or 4) Command Class for Binary Event Data (0–3) ECLASSB2 := Class for Counter Event Data (0–3) ECLASSC2 := Class for Analog Event Data (0–3) ECLASSA2 := Currents Scaling Decimal Places (0–3)
  • Page 291 (Hidden if UNSOL3 := N) PORT 2 (Fiber-Optic Serial Port in Slot B) (Hidden if E49RTD := EXT or Port 2 Not Included) PROTOCOL (SEL, DNP, MOD, EVMSG, PMU, MBA, MBB, PROTO MB8A, MB8B, MBTA, MBTB) Communications SPEED (300, 1200, 2400, 4800, 9600, 19200, 38400 bps)
  • Page 292 MODBUS SLAVE ID (1–247) SLAVEID (Hidden if PROTO := SEL, EVMSG, or MB_) DNP3 Protocol (Hidden if PROTO := SEL, EVMSG, MB, PMU, or MOD.) DNP Address (0–65519) DNPADR DNP Address to Report to (0–65519) REPADR1 := DNP Map (1–3) DNPMAP1 := Analog Input Default Variation (1–6)
  • Page 293 Unsolicited Message Offline Time-Out (1–5000 sec) UTIMEO1 := (Hidden if UNSOL1 := N) Protocol IRRORED (Hidden if PROTO := SEL, EVMSG, or MOD) MB Transmit Identifier (1–4) TXID MB Receive Identifier (1–4) RXID MB RX Bad Pickup Time (0–10000 seconds) RBADPU PPM MB Channel Bad Pickup (1–10000)
  • Page 294 MODBUS SLAVE ID (1–247) SLAVEID (Hidden if PROTO := SEL, EVMSG, or MB_) DNP3 Protocol (Hidden if PROTO := SEL, EVMSG, MB, PMU or MOD.) DNP Address (0–65519) DNPADR DNP Address to Report to (0–65519) REPADR1 := DNP Map (1–3) DNPMAP1 := Analog Input Default Variation (1–6)
  • Page 295 Time to Attempt Dial (5–300 sec) MDTIME Time Between Dial-Out Attempts (5–3600 sec) MDRET Protocol IRRORED (Hidden if PROTO := SEL, EVMSG, or MOD) MB Transmit Identifier (1–4) TXID MB Receive Identifier (1–4) RXID MB RX Bad Pickup Time (0–10000 seconds) RBADPU PPM MB Channel Bad Pickup (1–10000)
  • Page 296 RMB8 Dropout Debounce Messages (1–8) RMB8DO := PORT 4 (EIA-232/485 Port or DeviceNet Port in Slot C) (Hidden If Option Not Included) PROTOCOL (SEL, DNP, MOD, DNET, EVMSG, PMU, MBA, PROTO MBB, MB8A, MB8B, MBTA, MBTB) Interface Select (Hidden if PROTO := DNET)
  • Page 297 MODBUS SLAVE ID (1–247) SLAVEID (Hidden if PROTO := SEL, EVMSG, MB_, or DNET) DNP3 Protocol (Hidden if PROTO := SEL, EVMSG, MB, PMU , DNET or MOD.) DNP Address (0–65519) DNPADR DNP Address to Report to (0–65519) REPADR1 := DNP Map (1–3)
  • Page 298 Time to Attempt Dial (5–300 sec) MDTIME Time Between Dial-Out Attempts (5–3600 sec) MDRET Protocol IRRORED (Hidden if PROTO := SEL, EVMSG, or MOD) MB Transmit Identifier (1–4) TXID MB Receive Identifier (1–4) RXID MB RX Bad Pickup Time (0–10000 seconds) RBADPU PPM MB Channel Bad Pickup (1–10000)
  • Page 299 Date _______________ SEL-751A Settings Sheets SET.49 Front-Panel Settings (SET F Command) of 68 RMB6 Pickup Debounce Messages (1–8) RMB6PU RMB6 Dropout Debounce Messages (1–8) RMB6DO := RMB7 Pickup Debounce Messages (1–8) RMB7PU RMB7 Dropout Debounce Messages (1–8) RMB7DO := RMB8 Pickup Debounce Messages (1–8) RMB8PU RMB8 Dropout Debounce Messages (1–8)
  • Page 300 SET.50 SEL-751A Settings Sheets Date________________ of 68 Front-Panel Settings (SET F Command) PB3B_LED EQUATION (SEL PB3B_LED := OGIC PB4A_LED EQUATION (SEL PB4A_LED := OGIC PB4B_LED EQUATION (SEL PB4B_LED := OGIC Display Points Display Point Settings (maximum 60 characters): ➤ (Boolean): Relay Word Bit Name, "Alias", "Set String", "Clear String"...
  • Page 301 Date _______________ SEL-751A Settings Sheets SET.51 Front-Panel Settings (SET F Command) of 68 DISPLAY POINT DP28 (60 characters) DP28 DISPLAY POINT DP29 (60 characters) DP29 DISPLAY POINT DP30 (60 characters) DP30 DISPLAY POINT DP31 (60 characters) DP31 DISPLAY POINT DP32 (60 characters)
  • Page 302 SET.52 SEL-751A Settings Sheets Date________________ of 68 Front-Panel Settings (SET F Command) PULSE LB_ LABEL (7 characters) PLB07 LB_NAME (14 characters) NLB08 CLEAR LB_ LABEL (7 characters) CLB08 SET LB_ LABEL (7 characters) SLB08 PULSE LB_ LABEL (7 characters) PLB08...
  • Page 303 Date _______________ SEL-751A Settings Sheets SET.53 Front-Panel Settings (SET F Command) of 68 CLEAR LB_ LABEL (7 characters) CLB16 SET LB_ LABEL (7 characters) SLB16 PULSE LB_ LABEL (7 characters) PLB16 LB_NAME (14 characters) NLB17 CLEAR LB_ LABEL (7 characters)
  • Page 304 SET.54 SEL-751A Settings Sheets Date________________ of 68 Front-Panel Settings (SET F Command) PULSE LB_ LABEL (7 characters) PLB24 LB_NAME (14 characters) NLB25 CLEAR LB_ LABEL (7 characters) CLB25 SET LB_ LABEL (7 characters) SLB25 PULSE LB_ LABEL (7 characters) PLB25...
  • Page 305 Date _______________ SEL-751A Settings Sheets SET.55 Report Settings (SET R Command) of 68 Report Settings (SET R Command) SER Chatter Criteria Auto-Removal Enable (Y, N) ESERDEL := Number of Counts (2–20 counts) SRDLCNT := Removal Time (0.1–90.0 seconds) SRDLTIM := SER Trigger Lists SERn = Up to 24 Relay-Word elements separated by spaces or commas.
  • Page 306 SET.56 SEL-751A Settings Sheets Date________________ of 68 Modbus Map Settings (SET M Command) ALIAS19 ALIAS19 ALIAS20 ALIAS20 Event Report EVENT TRIGGER (SEL OGIC EVENT LENGTH (15,64 cyc) PREFAULT LENGTH (1–59 cyc {if LER := 15}, 1–10 cyc {if LER := 64})
  • Page 307 Date _______________ SEL-751A Settings Sheets SET.57 Modbus Map Settings (SET M Command) of 68 User Map Register Label Name (8 characters) MOD_020 User Map Register Label Name (8 characters) MOD_021 User Map Register Label Name (8 characters) MOD_022 User Map Register Label Name (8 characters)
  • Page 308 SET.58 SEL-751A Settings Sheets Date________________ of 68 Modbus Map Settings (SET M Command) User Map Register Label Name (8 characters) MOD_054 User Map Register Label Name (8 characters) MOD_055 User Map Register Label Name (8 characters) MOD_056 User Map Register Label Name (8 characters)
  • Page 309 Date _______________ SEL-751A Settings Sheets SET.59 Modbus Map Settings (SET M Command) of 68 User Map Register Label Name (8 characters) MOD_088 User Map Register Label Name (8 characters) MOD_089 User Map Register Label Name (8 characters) MOD_090 User Map Register Label Name (8 characters)
  • Page 310 SET.60 SEL-751A Settings Sheets Date________________ of 68 DNP3 Map Settings (SET DNP n Command) User Map Register Label Name (8 characters) MOD_122 User Map Register Label Name (8 characters) MOD_123 User Map Register Label Name (8 characters) MOD_124 User Map Register Label Name (8 characters)
  • Page 311 Date _______________ SEL-751A Settings Sheets SET.61 DNP3 Map Settings (SET DNP n Command) of 68 DNP Binary Input Label Name (10 characters) BI_23 DNP Binary Input Label Name (10 characters) BI_24 DNP Binary Input Label Name (10 characters) BI_25 DNP Binary Input Label Name (10 characters)
  • Page 312 SET.62 SEL-751A Settings Sheets Date________________ of 68 DNP3 Map Settings (SET DNP n Command) DNP Binary Input Label Name (10 characters) BI_57 DNP Binary Input Label Name (10 characters) BI_58 DNP Binary Input Label Name (10 characters) BI_59 DNP Binary Input Label Name (10 characters)
  • Page 313 Date _______________ SEL-751A Settings Sheets SET.63 DNP3 Map Settings (SET DNP n Command) of 68 DNP Binary Input Label Name (10 characters) BI_91 DNP Binary Input Label Name (10 characters) BI_92 DNP Binary Input Label Name (10 characters) BI_93 DNP Binary Input Label Name (10 characters)
  • Page 314 SET.64 SEL-751A Settings Sheets Date________________ of 68 DNP3 Map Settings (SET DNP n Command) DNP Binary Output Label Name (10 characters) BO_23 DNP Binary Output Label Name (10 characters) BO_24 DNP Binary Output Label Name (10 characters) BO_25 DNP Binary Output Label Name (10 characters)
  • Page 315 Date _______________ SEL-751A Settings Sheets SET.65 DNP3 Map Settings (SET DNP n Command) of 68 AI_25 AI_26 AI_27 AI_28 AI_29 AI_30 AI_31 AI_32 AI_33 AI_34 AI_35 AI_36 AI_37 AI_38 AI_39 AI_40 AI_41 AI_42 AI_43 AI_44 AI_45 AI_46 AI_47 AI_48 AI_49...
  • Page 316 SET.66 SEL-751A Settings Sheets Date________________ of 68 DNP3 Map Settings (SET DNP n Command) AI_63 AI_64 AI_65 AI_66 AI_67 AI_68 AI_69 AI_70 AI_71 AI_72 AI_73 AI_74 AI_75 AI_76 AI_77 AI_78 AI_79 AI_80 AI_81 AI_82 AI_83 AI_84 AI_85 AI_86 AI_87 AI_88...
  • Page 317 Date _______________ SEL-751A Settings Sheets SET.67 DNP3 Map Settings (SET DNP n Command) of 68 Analog Output Map DNP Analog Output Label Name (6 characters) AO_00 DNP Analog Output Label Name (6 characters) AO_01 DNP Analog Output Label Name (6 characters)
  • Page 318 SET.68 SEL-751A Settings Sheets Date________________ of 68 DNP3 Map Settings (SET DNP n Command) Counter Map DNP Counter Label Name (11 characters) CO_00 DNP Counter Label Name (11 characters) CO_01 DNP Counter Label Name (11 characters) CO_02 DNP Counter Label Name (11 characters)
  • Page 319 Rear Ordering Option Option 2: DeviceNet Communications Card This port can receive the RTD measurement information from the optional external SEL-2600 RTD Module. Refer to the applicable SEL-2600 RTD Module Instruction Manual for information on the fiber-optic interface. Refer to Appendix G: DeviceNet Communications for information on the DeviceNet communications card.
  • Page 320 Communications Interfaces Be sure to evaluate the installation and communications necessary to integrate with existing devices before ordering your SEL-751A. For example, consider the fiber-optic interface in noisy installations or for large communications distances. Following is general information on possible applications of the different interfaces.
  • Page 321 Ethernet Port Use the Ethernet port for interfacing with an Ethernet network environment. SEL-751A Ethernet port choices include single or dual copper or fiber-optic configurations. With dual Ethernet ports the unit has an unmanaged Ethernet switch. Redundant configurations support automatic failover switching from primary to backup network if a failure in the primary network is detected.
  • Page 322 Communications Communications Interfaces NETWORK CAT 5 shielded twisted pair (STP) cables with RJ-45 connectors (SEL-C627/C628) for copper Ethernet ports Fiber-optic Ethernet cables with Ethernet Switch B Ethernet Switch A LC connectors (SEL-C807) for fiber-optic Ethernet ports SEL-751A SEL-710 SEL-787 SEL-751A...
  • Page 323 Step 3. Set NETPORT to the preferred network interface. On startup the relay communicates via NETPORT (primary port) selected. If the SEL-751A detects a link failure on the primary port, it activates the standby port after the failover time, FTIME, elapses. If the link status on the...
  • Page 324 IRIG-B The SEL-751A has three different physical interfaces, depending on the model options, to provide demodulated IRIG-B time-code input for time synchronization. If the relay has multiple options for IRIG-B input, only one input can be used at a time.
  • Page 325 Cannot use B01–B02 input or Port 2 if Port 3 is used. Set Global setting IRIG TIME SOURCE to TIME_SRC := IRIG1. Figure 7.6 IRIG-B Input VIA EIA-232 Port 3 (SEL-2401/2404/2407 Time Source) Option 3: Port 2 (Fiber-Optic Serial Port)
  • Page 326 This +5 Vdc is available in any combination of Pins 1, 3, and 7 without the need for hardware jumpers. Connect Your The front port of the SEL-751A is a standard female 9-pin connector with pin numbering shown in Figure 7.9.
  • Page 327 D Subconnector D Subconnector Pin # Pin # Func. Func. *DTE = Data Terminal Equipment (Computer, Terminal, etc.) Figure 7.10 SEL Cable C234A—SEL-751A to DTE Device SEL-751A Relay *DTE Device 9-Pin Male 25-Pin Female D Subconnector D Subconnector Pin # Pin # Func.
  • Page 328 9-Pin Male 9-Pin Male D Subconnector D Subconnector Func. Pin # Pin # Func. Figure 7.13 SEL Cable C272A—SEL-751A to SEL Communications Processor Without IRIG-B Signal SEL Communications Processor SEL-751A Relay 9-Pin Male 9-Pin Male D Subconnector D Subconnector Func.

  • Page 329: Communications Protocols

    Communications Protocols Communications Protocols Protocols Although the SEL-751A supports a wide range of protocols, not all protocols are available on all ports. In addition, not all hardware options support all protocols. Be sure to select the correct hardware to support a particular protocol. For ®...
  • Page 330 The SEL-751A provides Modbus RTU support. Modbus is an optional protocol described in Appendix E: Modbus RTU Communications. DNP3 (Distributed Network Protocol) The SEL-751A provides DNP3 protocol support if the option is selected. The DNP3 protocol is described in Appendix D: DNP3 Communications. DeviceNet Protocol The SEL-751A provides DeviceNet Support.

  • Page 331: Sel Ascii Protocol And Commands

    IEC 61850 protocol, see Appendix F: IEC 61850 Communications. SEL ASCII Protocol and Commands Message Format SEL ASCII protocol is designed for manual and automatic communication. All commands the relay receives must be of the following form: <command><CR> <command><CRLF> NOTE: The <Enter>...
  • Page 332 The relay sends an event summary each time an event report is triggered. See Section 9: Analyzing Events. Self-Test Warning or The SEL-751A sends a status report each time a self-test Failure warning or failure condition is detected. See STATUS Com- mand (Relay Self-Test Status) on page 7.39.
  • Page 333 7.15 SEL ASCII Protocol and Commands Access Levels Commands can be issued to the SEL-751A via the serial port to view metering values, change relay settings, etc. The available serial port commands are listed in the SEL-751A Relay Command Summary at the end of this manual.
  • Page 334 ➤ The Access Level 0 commands provide the first layer of security. In addition, Access Level 0 supports several commands required by SEL communications processors. ➤ The Access Level 1 commands are primarily for reviewing information only (settings, metering, etc.), not changing it.
  • Page 335 Communications 7.17 SEL ASCII Protocol and Commands Command This section lists ASCII commands alphabetically. Commands, command options, and command variables to enter are shown in bold. Lowercase italic Explanations letters and words in a command represent command variables that are determined based on the application.
  • Page 336 7.18 Communications SEL ASCII Protocol and Commands Because the password is not disabled, the relay prompts you for the Access Level 1 password: Password: ? The relay is shipped with the default Access Level 1 password shown in PASSWORD Command (Change Passwords) on page 7.33.
  • Page 337 Communications 7.19 SEL ASCII Protocol and Commands =>>AFT Arc Flash Diagnostic in progress ... . . SEL-751A Date: 12/09/2008 Time: 09:20:13 FEEDER RELAY Time Source: Internal Channel # Sensor Test Light Limits...
  • Page 338 7.20 Communications SEL ASCII Protocol and Commands When parameter p is a ramp function, the device displays the following message during the test: Ramping Analog Output at xx.xx [units]/min; full scale in y.y minutes. Press any key to end test where: xx.xx...
  • Page 339 Communications 7.21 SEL ASCII Protocol and Commands BRE Command (Breaker Monitor Data) Use the BRE command to view the breaker monitor report. =>>BRE <Enter> SEL-751A Date: 12/04/2008 Time: 14:26:57 FEEDER RELAY Time Source: External Trip Counters Rly Trips (counts) Ext Trips (counts)
  • Page 340 Breaker Monitor on page 5.15 for further details on the breaker monitor. CEV Command The SEL-751A provides Compressed ASCII event reports to facilitate event report storage and display. SEL communications processors and the SEL-5601 Analytic Assistant software take advantage of the Compressed ASCII format.
  • Page 341 Communications 7.23 SEL ASCII Protocol and Commands ➤ Parity error ➤ Overrun ➤ Re-sync ➤ Data error ➤ Loopback ➤ Underrun Table 7.9 COM Command Command Description Access Level COM S A or Return a summary report of the last 255 records in...
  • Page 342 7.24 Communications SEL ASCII Protocol and Commands For example, use the following command to set Remote bit RB05: =>>CON RB05 S <Enter> COPY Command Use the COPY j k command (see Table 7.12) to copy the settings of settings Group j to the settings of settings Group k. The settings of settings Group j effectively overwrite the settings of settings Group k.
  • Page 343 Communications 7.25 SEL ASCII Protocol and Commands =>>ETH <Enter> SEL-751A Date: 06/05/2008 Time: 10:41:37 FEEDER RELAY Time Source: Internal MAC: 00-30-A7-00-75-6A IP ADDRESS: 192.168.1.2 SUBNET MASK: 255.255.255.0 DEFAULT GATEWAY: 192.168.1.1 PRIMARY PORT: PORT 1A ACTIVE PORT: PORT 1B LINK SPEED...
  • Page 344 7.26 Communications SEL ASCII Protocol and Commands FILE Command The FIL command (see Table 7.17) is intended to be a safe and efficient means of transferring files between intelligent electronic devices (IEDs) and external support software (ESS). The FIL command ignores the hide rules and transfers visible as well as hidden settings, except the settings hidden by a part number.
  • Page 345 Communications 7.27 SEL ASCII Protocol and Commands Description (Time to Live) This field contains the time (in ms) before the next message is expected. Code This text field contains warning or error condition text when appro- priate that is abbreviated as follows:...
  • Page 346 7.28 Communications SEL ASCII Protocol and Commands An example response to the GOOSE commands is shown in Figure 7.19. #>GOOSE <Enter> GOOSE Transmit Status MultiCastAddr Ptag:Vlan StNum SqNum Code ----------------------------------------------------------------------------- SEL_751A_2CFG/LLN0$GO$GooseDSet13 01-0C-CD-01-00-04 20376 Data Set: SEL_751A_2CFG/LLN0$DSet13 GOOSE Receive Status MultiCastAddr...
  • Page 347 Communications 7.29 SEL ASCII Protocol and Commands HELP Command The HELP command (see Table 7.20) gives a list of commands available at the present access level. You can also get a description of any particular command; type HELP followed by the name of the command for help on each command.
  • Page 348 7.30 Communications SEL ASCII Protocol and Commands If the relay successfully synchronizes to IRIG-B, it sends the following header and access level prompt: SEL-751A Date: 12/10/2003 Time: 08:56:03.190 FEEDER RELAY Time Source: external => If no IRIG-B code is present at the serial port input or if the code cannot be...
  • Page 349 Communications 7.31 SEL ASCII Protocol and Commands Table 7.26 L_D Command (Load Firmware) Command Description Access Level Download firmware to the control. Only download firmware to the front port. LOOPBACK Command The LOO command (see Table 7.27) is used for testing the M IRRORED communications channel for proper communication.
  • Page 350 7.32 Communications SEL ASCII Protocol and Commands MAC Command Use the MAC command to display the MAC addresses of PORT 1, as shown below. =>MAC <Enter> Port 1 MAC Address: 00-30-A7-00-00-00 => MET Command (Metering Data) The MET command (see Table 7.28,...
  • Page 351 Parameter level represents the relay Access Levels 1 or 2. password may allow unauthorized access. SEL shall not be responsible The factory default passwords are as shown in Table 7.33. for any damage resulting from unauthorized access.
  • Page 352 7.34 Communications SEL ASCII Protocol and Commands Table 7.34 Valid Password Characters Alpha A B C D E F G H I J K L M N O P Q R S T U V W X Y Z a b c d e f g h i j k l m n o p q r s t u v w x y z...
  • Page 353 Access Level QUIT Go to Access Level 0. Access Level 0 is the lowest access level; the SEL-751A performs no password check to descend to this level (or to remain at this level). R_S Command (Restore Factory Defaults) Use the R_S command (see Table 7.37) to restore factory default settings.
  • Page 354 7.36 Communications SEL ASCII Protocol and Commands Table 7.39 SER Command Format Parameter Description row1 Append row1 to return a chronological progression of the first row1 rows. For example, use SER 5 to return the first five rows. row1 row2 Append row1 and row2 to return all rows between row1 and row2, beginning with row1 and ending with row2.
  • Page 355 Communications 7.37 SEL ASCII Protocol and Commands Table 7.41 SET Command (Change Settings) (Sheet 2 of 2) Command Description Access Level SET P n s TERSE Set serial port settings. n specifies the PORT (1, 2, 3, 4, or F); n defaults to the active port if not listed.
  • Page 356 7.38 Communications SEL ASCII Protocol and Commands Table 7.44 SHOW Command (Show/View Settings) Command Description Access Level SHO n s Show Relay settings for group n (n = 1, 2, or 3). SHO L n s Show general logic settings for group n (n = 1, 2, or SHO G s Show global settings.
  • Page 357 Communications 7.39 SEL ASCII Protocol and Commands Negative Seq TOC 51QP := 6.00 51QC := U3 51QTD := 3.00 51QRS := N 51QCT := 0.00 51QMR := 0.00 51QTC := 1 Neutral TOC 51N1P := OFF 51N2P := OFF Residual TOC 51G1P := 0.50...
  • Page 358 7.40 Communications SEL ASCII Protocol and Commands Table 7.47 STATUS Command Report and Definitions STATUS Report Designator Definition Message Format Serial Num Serial number Number Firmware identifier string Text Data Firmware checksum identifier PART NUM Part number Text Data FPGA...
  • Page 359 Table 7.51. All Relay Word rows are described in Table J.1 Table J.2. Relay Word bits are used in SEL control equations. See Appendix J: OGIC Relay Word Bits. The TAR command does not remap the front-panel target LEDs, as is done in some previous SEL relays.
  • Page 360 The TIME command (see Table 7.52) returns information about the SEL-751A internal clock. You can also set the clock if you specify hours and minutes (seconds data are optional). Separate the hours, minutes, and seconds with colons, semicolons, spaces, commas, or slashes.

  • Page 361: Human-Machine Interface

    The SEL-751A features a straightforward menu-driven control structure presented on the front-panel liquid crystal display (LCD). Front- panel targets and other LEDs give a clear indication of the SEL-751A operation status. The features that help you operate the relay from the front panel include the following: ➤...
  • Page 362 You can adjust the LCD screen contrast to suit your viewing angle and lighting conditions. To change screen contrast, press and hold the {ESC} pushbutton for two seconds. The SEL-751A displays a contrast adjustment NOTE: See the Preface for an explanation of typographic box.
  • Page 363 Front-Panel Security Front-Panel Access Levels The SEL-751A front panel typically operates at Access Level 1 and provides viewing of relay measurements and settings. Some activities, such as editing settings and controlling output contacts, are restricted to those operators who know the Access Level 2 passwords.
  • Page 364 Front-Panel Menus and Screens Navigating the Menus The SEL-751A front panel gives you access to most of the information that the relay measures and stores. You can also use front-panel controls to view or modify relay settings. All of the front-panel functions are accessible through use of the six-button keypad and LCD display.
  • Page 365 Select the menu item at the cursor. Select the displayed setting to edit that setting. The SEL-751A automatically scrolls information that requires more space than provided by a 16-character LCD line. Use the {Left Arrow} and {Right Arrow} pushbuttons to suspend automatic scrolling and enable manual scrolling of this information.
  • Page 366 Figure 8.9 Relay Response When No Analog Cards Are Installed Assume the math variables are not enabled. In response to a request for math variable data (selecting ), the device displays the message as Math Variables shown in Figure 8.10. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 367 Clear EVENTS the relay displays as shown in Figure 8.14 after clearing the events data. Clearing Complete Figure 8.14 Relay Response When Events Are Cleared Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 368 Local Bits Select the menu item to assert Relay Word bit OC that opens the breaker Open OGIC ® via the TR SEL equation (see Table 4.22 for the TR equation and Table J.2 for the definition of the OC bit). Note that this requires Level 2 access.
  • Page 369 Outputs CONTROL Figure 8.18 to test (pulse) SEL-751A output contacts and associated circuits. Choose the output contact by navigating through the menu and test it OUTPUT by pressing the {ENT} pushbutton. Note that testing the output contact requires Level 2 access and reconfirmation.
  • Page 370 {Up Arrow} and {Down Arrow} pushbuttons to change the value. Press the {ENT} pushbutton to enter the new setting. ® Setting changes can also be made using QuickSet SEL-5030 ERATOR Software or ASCII SET commands via a communications port. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 371 Self-Test Status) on page 7.39 for the STATUS data field description. MAIN Meter Events Targets Control (Status Selected) Set/Show STATUS Status Relay Status Breaker Arc Flash Status Reboot Relay Figure 8.22 MAIN Menu and Status Submenu Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 372: Operation And Target Leds

    Reset Figure 8.23 MAIN Menu and Breaker Submenu Operation and Target LEDs Programmable LEDs The SEL-751A provides quick confirmation of relay conditions via operation and target LEDs. Figure 8.24 shows this region with factory default text on the front-panel configurable labels. See Target LED Settings on page 4.120...
  • Page 373 Front-Panel Operations 8.13 Operation and Target LEDs The SEL-751A can be ordered with optional slide-in labels for custom LED designations that match custom LED logic. The Configurable Label kit (includes blank labels, word processor templates, and instructions) is provided when the SEL-751A is ordered with the Configurable Labels option.
  • Page 374 LEDs are independent of the pushbutton. Pushbutton LEDs are programmable using front-panel settings PBnm_LED (where n = 1 through 4 and m = A or B). PBnm _LED settings are SEL OGIC control equations that, when asserted, illuminate the corresponding LED for as long as the input is asserted.
  • Page 375 Option: Set a delay, so the operator can press the {TRIP} operator control pushbutton and BREAKER OPEN then move a safe distance away from the breaker before the SEL-751A issues a trip (the {TRIP} operator control comes with no set delay in the factory settings). With a set delay, press the {TRIP} operator control pushbutton momentarily and notice the corresponding BREAKER OPEN LED flashes on and off during the delay time, indicating a pending trip.
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  • Page 377: Event Reporting

    Section 9 Analyzing Events Overview The SEL-751A Feeder Protection Relay provides several tools (listed below) to analyze the cause of relay operations. Use these tools to help diagnose the cause of the relay operation and more quickly restore the protected equipment to service.
  • Page 378 Refer to the SET R command in SET Command (Change Settings) on page 7.36 Report Settings (SET R Command) on page SET.55. Triggering The SEL-751A triggers (generates) an event report when any of the following occur: ➤ Relay Word bit TRIP asserts ➤ OGIC ®...
  • Page 379 Analyzing Events Event Reporting detects a logical 0 to logical 1 transition, it generates an event report (if the SEL-751A is not already generating a report that encompasses the new transition). The factory setting is shown in Event Report Settings on page 4.124.
  • Page 380 27 Trip (27P1T OR 27P2T) AND NOT LOP AND TRIP RTD Fail Trip RTDFLT AND TRIP Breaker Failure Trip BFT AND TRIP CommIdleLossTrip (COMMIDLE OR COMMLOSS) AND TRIP Trigger Serial port TRI command SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 381 See Figure 9.2 for a sample event history. Use this report to view the events that are presently stored in the SEL-751A. The event history contains the following: ➤ Standard report header ➢...
  • Page 382 HIS command. Use the front-panel menu to display event history MAIN > Events > Display data on the SEL-751A front-panel display. Use the QuickSet software to retrieve the relay event history. ERATOR View the Relay Event History dialog box via the Tools > Events > Get Event Files menu.
  • Page 383 Event Reporting Filtered and Unfiltered Event Reports The SEL-751A samples the power system measurands (ac voltage and ac current) 16 times per power system cycle. A digital filter extracts the fundamental frequency component of the measurands. The relay operates on the filtered values and reports these values in the standard, filtered event report.
  • Page 384 81D1T OR 81D2T OR 81D3T OR 81D4T OR 81D5T OR 81D6T RTD Wdg (SEL-2600 WDGALRM AND NOT WDGTRIP RTD Module or RTD WDGTRIP card required) RTD Brg (SEL-2600 BRGALRM AND NOT BRGTRIP RTD Module or RTD BRGTRIP card required) SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 385 9.5). These currents are listed at the end of the event report in the event summary. If the trigger row ( ) and the maximum > phase current row ( ) are the same row, the symbol takes precedence. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 386 8183 48 ..3 -148 -436 -4.2 7297 3483 -10715 7047 48 ..3 -158 -414 12.0 -8111 10341 -2088 -8188 48 ... SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 387 Analyzing Events 9.11 Event Reporting Serial No = 2008xxxxxxxxxxx Firmware Identifier FID = SEL-751A-X215-V0-Z003002-D20080530 CID = 0E1E Firmware Checksum Identifier EVENT LOGS = Event: ER Trigger Targets 11100001 Freq (Hz) 60.0 Current Mag 1806.6 1796.0 1796.0 0.00 16.94 Voltage Mag...
  • Page 388 Figure 9.5 shows how the event report current column data can be converted to phasor rms values. Voltages are processed similarly. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 389 Equation 9.1 The present sample (IA = 940.7 A) is a real rms current value that relates to the phasor rms current value: – ( 1204 A • cos 38.6° 940.7 A Equation 9.2 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 390 X = 940.7 Real Axis Angle = Arctan —750.3 = Arctan 940.7 = –38.6˚ Magnitude = (—750.3) + (940.7) = 1204 Figure 9.5 Derivation of Phasor RMS Current Values From Event Report Current Values SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 391 Figure 9.3. =>SER 8 <Enter> SEL-751A Date: 02/28/2007 Time: 16:34:28 FEEDER RELAY Time Source: Internal Serial No = 2007XXXXXXXXXXX FID = SEL-751A-R100-V0-Z001001-D20070410 CID = 5052 DATE TIME ELEMENT STATE 02/28/2007 13:54:09.602 51P1P Asserted 02/28/2007 13:54:09.602...
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  • Page 393 ➤ Tests performed periodically once the relay is in service This section provides information on both types of testing for the SEL-751A Feeder Protection Relay. Because the SEL-751A is equipped with extensive self-tests, traditional periodic test procedures may be eliminated or greatly reduced.

  • Page 394: Commissioning Tests

    Commissioning tests confirm that the relay is properly connected including the control signal inputs and outputs. The following connection tests help you enter settings into the SEL-751A and verify that the relay is properly connected. Brief functional tests ensure that the relay settings are correct.
  • Page 395 Step 8. Using the SET, SET P, SET G, SET L, and SET R serial port commands, enter the relay settings from the settings sheets for your application. Step 9. If you are connecting an external SEL-2600 RTD Module, follow the substeps below; otherwise continue with the next step.
  • Page 396 Repeat the process for all contact outputs. Make sure that each contact closure does what you want it to do in the annunciation, control, or trip circuit associated with that contact closure. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 397 Phase voltage magnitudes should be nearly equal. ➢ Phase voltage phase angles should be balanced and have proper phase rotation. The SEL-751A is now ready for continuous service. Functional Tests Phase Current Measuring Accuracy Step 1. Connect the current source to the relay, as shown in Figure 10.3.
  • Page 398 |I| Applied (A secondary) Expected Reading (%) Actual Reading (%) |IA| = 0.9 • |IB| = |IC| = |IA| = 0.75 • |IB| = |IC| = |IA| = |IB| = 1.2 • |IC| = 1.2 • SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 399 Q = 0.2211 • CTR • PTR pf = 0.90 lag Ib = 2.5 ∠− 146 Ic = 2.5 ∠+94 Va = 67 ∠0 Measured: Measured: Measured: Vb = 67 ∠− 120 Vc = 67 ∠+120 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 400 P = 0.4677 • CTR • PTR Q = 0.2286 • CTR • PTR pf = 0.90 lag Ib = 2.5 ∠–146 Ic = 2.5 ∠+94 Vab = 120 ∠+30 Measured: Measured: Measured: Vbc = 120 ∠–90 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 401 ENABLED state. Arc-Flash Detection (AFD) System Continuous Self-Testing The SEL-751A relay continuously tests (periodic) and monitors all four arc- flash sensor subsystems and reports the status. The test period is constant, set to 10 minutes.
  • Page 402 This same test is also available from the Control Window in the ® QuickSet SEL-5030 Software and the relay front panel ERATOR STATUS sub-menu. Refer to Figure 7.16 for the AFT command response example.

  • Page 403: Periodic Tests (Routine Maintenance)

    Such reviews frequently reveal problems with equipment external to the relay, such as instrument transformers and control wiring. The SEL-751A does not require specific routine tests, but your operation standards may require some degree of periodic relay verification. If you need or want to perform periodic relay verification, the following checks are recommended.

  • Page 404: Self-Test

    Testing and Troubleshooting Self-Test Self-Test The SEL-751A runs a variety of self-tests. Two Relay Word bits, HALARM and SALARM, signal self-test problems. SALARM is pulsed for software- programmed conditions, such as settings changes, access level changes, and three consecutive unsuccessful password entry attempts. HALARM is pulsed for hardware self-test warnings.
  • Page 405 Fail on lack of data acquisition inter- Latched FPGA Failure (run time) rupts External RTD Fail if no comm, or the external RTD module reports open RTDs, shorted RTDs, a power supply failure Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 406: Troubleshooting

    Verify the relay settings. Improper test source settings Verify the test source settings. Current or voltage input wiring error Verify input wiring. Failed relay self-test Use the front-panel RELAY STATUS function to view self-test results. SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 407: Factory Assistance

    Testing and Troubleshooting 10.15 Factory Assistance Factory Assistance We appreciate your interest in SEL products and services. If you have questions or comments, please contact us at: Schweitzer Engineering Laboratories, Inc. 2350 NE Hopkins Court Pullman, WA 99163-5603 USA Tel: +1.509.332.1890 Fax: +1.509.332.7990...
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  • Page 409 Appendix A Firmware and Manual Versions Firmware Determining the To find the firmware version number in your SEL-751A Feeder Protection Relay, use the STA command (see STATUS Command (Relay Self-Test Status) Firmware Version on page 7.39 for more information on the STA command). The firmware in Your Relay revision number is after the R, and the release date is after the D.
  • Page 410 Added DNP3 serial and LAN/WAN protocol options. ➤ Added synchrophasor measurements, metering, and C37.118 Protocol to the SEL-751A base model. ➤ Added breaker monitor function to the SEL-751A base model. ➤ Added demand and peak demand metering option to selected models.
  • Page 411 20080325 power up to MMS for IEC 61850 protocol. ➤ Corrected setting change function using Modbus Function Code 06 when voltage board is not installed. ➤ Corrected SER captures of digital input transitions. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 412 Versions ICD files, so the ICD file version number and CID file version number are the same. If downloaded to the SEL-751A, an incompatible CID file will generate file parse errors during processing and disable the IEC 61850 protocol. If you perform an SEL-751A firmware upgrade that spans different file version compatibilities, the relay may be unable to process the stored CID file.
  • Page 413 Command Response—No Communications Card or EIA-232 EIA-485 Communications Card and 1.4: STA Command Response—Communications Card/DeviceNet Protocol. Section 2 ➤ Updated Figure 2.7: Pins for Password, Breaker Control, and SEL Jumper to show jumper locations on BOOT updated processor card. Section 4 ➤...
  • Page 414 Updated Table C.9: Communications Processor TARGET Region. Appendix D ➤ New release. Appendix E ➤ Updated Modbus map for the new functions added. Appendix F ➤ Updated for ICD Ver 002 R300. ➤ Updated the logical device tables. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 415 VS and VDC quantities. Section 10 ➤ Removed power supply warning self-tests from Table 10.7: Relay Self-Tests. Appendix A ➤ Updated for firmware version R200. Appendix C ➤ Added VS and VDC to metering data. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 416 Revised Fiber-Optic Serial Port information. ➤ Updated Figure 2.12: Control I/O Connections—Internal RTD Option. ➤ Updated Figure 2.18: SEL-751A Provides Overcurrent Protection for a Distribution Feeder–Figure 2.21: SEL-751A Provides Overcurrent Protection for a Transformer Bank With a Tertiary Winding. Section 3 ➤...
  • Page 417 Section 6 ➤ Added Input Debounce Settings to SEL-751A Settings Sheets. Section 7 ➤ Updated Table 7.1: SEL-751A Communication Port Interfaces, Table 7.31: PASSWORD Command, and Table 7.32: PAS Command Format. Section 8 ➤ Updated Configurable Label information in Programmable LEDs.
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  • Page 419 Overview SEL occasionally offers firmware upgrades to improve the performance of your relay. Because the SEL-751A Feeder Protection Relay stores firmware in flash memory, changing physical components is not necessary. Upgrade the relay firmware by downloading a file from a personal computer to the relay via the front-panel serial port as outlined in the following sections.
  • Page 420 STATUS FAIL EEPROM FAILURE Non_Vol , use the following procedure to restore the factory Failure default settings: a. Set the communications software settings to 9600 baud, 8 data bits, and 1 stop bit. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 421 Communications Processor connected. This step re-establishes automatic data collection between the SEL-2032, SEL-2030, SEL-2020 Communications Processor and the SEL relay. Failure to perform this step can result in automatic data collection failure when cycling communications processor power. Complete Step 16 only if your relay supports the IEC 61850 protocol.
  • Page 422 In the Telnet session, type GOO and press <Enter> e. View the GOOSE status and verify that the transmitted and received messages are as expected. The relay is now ready for your commissioning procedure. SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 423: Sel Communications Protocols

    We originally designed SEL ASCII commands for communication between the relay and a human operator via a keyboard and monitor or a printing terminal. A computer with a serial port can also use the SEL ASCII protocol to communicate with the relay, collect data, and issue commands.
  • Page 424 Relay identification ASCII names for SER data reported in Fast Meter Interleaved ASCII and SEL relays have two separate data streams that share the same physical serial port. Human data communications with the relay consist of ASCII character Binary Messages commands and reports that you view through use of a terminal or terminal emulation package.

  • Page 425: Sel Communications Processor

    ➤ Automated dial-out on alarms The SEL communications processors have 16 serial ports plus a front port. This port configuration does not limit the size of a substation integration project, because you can create a multitiered solution as shown in Figure C.2.
  • Page 426 You can add additional communications processors to provide redundancy and eliminate possible single points of failure. SEL communications processors provide an integration solution with a reliability comparable to that of SEL relays. In terms of MTBF (mean time between failures), SEL communications processors are 100 to 1000 times more reliable than computer-based and industrial technology-based solutions.

  • Page 427: Sel Communications Processor And Relay Architecture

    SEL communications processors equipped with an SEL-2701 Ethernet Processor can provide a UCA2 interface to SEL-751A relays and other serial IEDs. The SEL-751A data appear in models in a virtual device domain. The combination of the SEL-2701 with an SEL communications processor offers a significant cost savings because you can use existing IEDs or purchase less expensive IEDs.
  • Page 428 SEL Communications Processors SEL Communications Processor and Relay Architecture Enhancing You can also use an SEL communications processor to enhance a multidrop architecture similar to the one shown in Figure C.3. In this example, the SEL Multidrop Networks communications processor enhances a system that uses the SEL-2701 with an Ethernet HMI multidrop network.

  • Page 429: Sel Communications Processor Example

    SEL Communications Processors SEL Communications Processor Example SEL Communications Processor Example This example demonstrates the data and control points available in the SEL communications processor when you connect an SEL-751A. The physical configuration used in this example is shown in Figure C.4.
  • Page 430 No USER region registers reserved Table C.7 shows the map of regions in the SEL communications processor for data collected from the SEL-751A. Use the MAP n command to view these data. Table C.7 SEL Communications Processor Port 1 Region Map...
  • Page 431 Relay Metering Data Table C.8 shows the list of meter data available in the SEL communications processor and the location and data type for the memory areas within D1 (Data Region 1). The type field indicates the data type and size. The int type is a 16-bit integer.
  • Page 432 SEL-751A that asserts the OC bit for one processing interval. If you clear BR1, the SEL communications processor sends a message to the SEL-751A that asserts the CC bit for one processing interval. OC will open the breaker (via SEL...
  • Page 433 Demand Data Table C.10 lists the demand data available in the SEL Communications Processor and the location and data type for the memory areas within D3 (Data Region 3). The type field indicates the data type and size. The type “int”...
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  • Page 435 Appendix D DNP3 Communications Overview The SEL-751A Transformer Protection Relay provides a Distributed Network Protocol Version 3.0 (DNP3) Level 2 Slave interface for direct serial and LAN/WAN network connections to the device. This section covers the following topics: ➤ Introduction to DNP3 ➤...
  • Page 436 DNP3 terminology describes all points from the perspective of the master. Binary points for control that move from the master to the remote are called Binary Outputs, while binary status points within the remote are called Binary Inputs. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 437 For example, you can poll once a minute for Class 1 data, once an hour for Class 2 data, and once a day for Class 3 data. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 438 Table D.14 describes control point operation for the SEL-751A. Conformance Testing In addition to the protocol specifications, the DNP Users Group has approved conformance-testing requirements for Level 1 and Level 2 devices. Some implementers perform their own conformance specification testing, while some contract with independent companies to perform conformance testing.
  • Page 439 ➤ Ethernet is the recommended physical link, though others may up at the application layer by confirmations when required. be used ➤ TCP must be used for WANs Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 440: Dnp3 In The Sel-751A

    Data Access Table D.5 lists DNP3 data access methods along with corresponding SEL-751A settings. You must select a data access method and configure each DNP3 master for polling as specified. Table D.5 DNP3 Access Methods (Sheet 1 of 2) NOTE:...
  • Page 441 You may then place low priority data in event class 2 with higher thresholds. If the SEL-751A does not receive an Application Confirm in response to unsolicited data, it will wait for ETIMEOn seconds and then repeat the unsolicited message.
  • Page 442 For example, if you use the settings of 0.10 seconds for MAXDLY and 0.05 seconds for MINDLY, the SEL-751A will insert a random delay of 50 to 100 ms (milliseconds) between the end of carrier detection and the start of...
  • Page 443 NUMEVEn. The device also sends an unsolicited report if the age of the oldest event in the master n buffer exceeds AGEEVEn. The SEL-751A has the buffer capacities listed in Table D.6.
  • Page 444 LAN/WAN). By default, the SEL-751A accepts and ignores time set requests (TIMERQn=I). (This mode allows the SEL-751A to use a high accuracy, IRIG time source, but still interoperate with DNP3 masters that send time synchronization messages.) It can be set to request time synchronization periodically by setting the TIMERQn setting to the desired period.
  • Page 445 D.11 DNP3 in the SEL-751A DNP3 Settings The DNP3 port configuration settings available on the SEL-751A are shown Table D.7. You can enable DNP3 on Ethernet Port 1 or on any of the serial Ports 2 through 4, up to a maximum of three concurrent DNP3 sessions. Each session defines the characteristics of the connected DNP3 Master, to which you assign one of the three available custom maps.
  • Page 446 D.12 DNP3 Communications DNP3 in the SEL-751A Table D.7 Port DNP3 Protocol Settings (Sheet 2 of 2) Name Description Range Default Session 2 Settings DNPIP2 IP address (zzz.yyy.xxx.www) 15 characters “” DNPTR2 Transport protocol UDP, TCP · · · URETRY2 Unsolicited messages maximum retry attempts 2–10...
  • Page 447 D.13 DNP3 in the SEL-751A Configurable Data One of the most powerful features of the SEL-751A implementation is the ability to remap DNP3 data and, for analog values, specify per-point scaling Mapping and dead bands. Remapping is the process of selecting data from the reference map and organizing it into a data subset optimized for your application.
  • Page 448 D.14 DNP3 Communications DNP3 in the SEL-751A You can use the SHOW DNP x <Enter> command to view the DNP3 data map settings, where x is the DNP3 map number from 1 to 3. See Figure D.3 for an example display of map 1.
  • Page 449 You can use the command SET DNP x, where x is the map number, to edit or create custom DNP3 data maps. You can also use the ERATOR ® QuickSet SEL-5030 Software, which is recommended for this purpose. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 450 The following example describes how to create a custom DNP3 map by point type. The example demonstrates the SEL ASCII command SET DNP for each point type, but the entire configuration may be completed without saving changes between point types.
  • Page 451 DNP3 Communications D.17 DNP3 in the SEL-751A Table D.9 Sample Custom DNP3 AI Map Desired Point Description Label Scaling Deadband Index IA magnitude IA_MAG default default IB magnitude IB_MAG default default IC magnitude IC_MAG default default IN magnitude IN_MAG default...
  • Page 452 D.18 DNP3 Communications DNP3 in the SEL-751A Figure D.6 Analog Input Map Entry in QuickSet Software ERATOR Figure D.7 AI Point Label, Scaling and Deadband in QuickSet ERATOR Software The SET DNP x CO_00 <Enter> command allows you to populate the DNP counter map with per-point dead bands.
  • Page 453 DNP3 Communications D.19 DNP3 in the SEL-751A =>>SET DNP 1 BO_00 TERSE <Enter> Binary Output Map DNP Binary Output Label Name (23 characters) BO_00 := NA ? > RB01 <Enter> DNP Binary Output Label Name (23 characters) BO_01 := NA ? >...

  • Page 454: Dnp3 Documentation

    Default counter object/variation Object 20, Variation 6 Counter roll-over 16 bits Sends multifragment responses In response to the delay measurement function code, the SEL-751A will return a time delay accurate to within 50 milliseconds. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 455 Table D.11 lists the objects and variations with supported function codes and qualifier codes available in the SEL-751A. The list of supported objects conforms to the format laid out in the DNP specifications and includes both supported and unsupported objects. Those that are supported include the function and qualifier codes.
  • Page 456 D.22 DNP3 Communications DNP3 Documentation Table D.11 SEL-751A DNP Object List (Sheet 2 of 5) Request Response Obj. Var. Description Funct. Codes Qual. Codes Funct. Codes Qual. Codes 32-Bit Frozen Counter Without Flag 16-Bit Frozen Counter Without Flag 32-Bit Frozen Delta Counter Without Flag 16-Bit Frozen Delta Counter Without Flag Counter Change Event—All Variations...
  • Page 457 DNP3 Communications D.23 DNP3 Documentation Table D.11 SEL-751A DNP Object List (Sheet 3 of 5) Request Response Obj. Var. Description Funct. Codes Qual. Codes Funct. Codes Qual. Codes 16-Bit Frozen Analog Input With Time of Freeze 32-Bit Frozen Analog Input Without Flag...
  • Page 458 D.24 DNP3 Communications DNP3 Documentation Table D.11 SEL-751A DNP Object List (Sheet 4 of 5) Request Response Obj. Var. Description Funct. Codes Qual. Codes Funct. Codes Qual. Codes Short Floating Point Analog Output Block 3, 4, 5, 6 17, 28 echo of request Time and Date—All Variations...
  • Page 459 SEL-751A reference data map. The reference map shows the data available to a DNP3 master. You can use the default map or the custom DNP3 mapping functions of the SEL-751A to retrieve only the points required by your application.
  • Page 460 Although not shown as part SEL-751A part number. Table D.13 shows the SEL-751A default data map. If of the reference maps you may use the default maps are not appropriate, you can also use the custom DNP any Relay Word bit label when creating custom maps.
  • Page 461 Object 34 dead bands after a warm (HIS C) or cold start (power cycle). Input cards in slots 3, 4, and 5. If present, the SEL-751A adds each analog input point label, AIx0y (where x is the slot and y is the point number), to the default map in numerical order to the DNP map.
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  • Page 463 Enable Modbus TCP protocol with the optional Ethernet port settings. The SEL-751A supports up to two Modbus TCP sessions. The TCP port number for each session is selected with the Ethernet port settings. The default TCP port number is the Modbus TCP registered port 502. Modbus TCP uses the device IP address as the Modbus identifier and accesses the data in the relay using the same function codes and data maps as Modbus RTU.

  • Page 464: Communications Protocol

    Cyclical Redundancy Check (CRC) 2 bytes The SEL-751A SLAVEID setting defines the device address. Set this value to a unique number for each device on the Modbus network. For Modbus communication to operate properly, no two slave devices may have the same address.
  • Page 465 E.4. Note that the Command SEL-751A coil addresses start at 0 (e.g., Coil 1 is located at address zero). The coil status is packed one coil per bit of the data field. The Least Significant Bit (LSB) of the first data byte contains the starting coil address in the query. The other coils follow towards the high order end of this byte and from low order to high order in subsequent bytes.
  • Page 466 2 bytes CRC-16 To build the response, the SEL-751A calculates the number of bytes required to contain the number of bits requested. If the number of bits requested is not evenly divisible by eight, the device adds one more byte to maintain the balance of bits, padded by zeroes to make an even byte.
  • Page 467 (Relay Word bits) available in the device. Note that the command depends on the device hardware configuration; the device responds only to installed cards. Table E.7 02h SEL-751A Inputs (Sheet 1 of 4) Coil Address Function Code...
  • Page 468 Modbus RTU Communications Communications Protocol Table E.7 02h SEL-751A Inputs (Sheet 2 of 4) Coil Address Function Code Coil Description (Decimal) Supported 176–183 Relay Element Status Row 22 184–191 Relay Element Status Row 23 192–199 Relay Element Status Row 24 200–207...
  • Page 469 Modbus RTU Communications Communications Protocol Table E.7 02h SEL-751A Inputs (Sheet 3 of 4) Coil Address Function Code Coil Description (Decimal) Supported 496–503 Relay Element Status Row 62 504–511 Relay Element Status Row 63 512–519 Relay Element Status Row 64 520–527...
  • Page 470 Modbus RTU Communications Communications Protocol Table E.7 02h SEL-751A Inputs (Sheet 4 of 4) Coil Address Function Code Coil Description (Decimal) Supported 816–823 Relay Element Status Row 102 824–831 Relay Element Status Row 103 832–839 Relay Element Status Row 104 840–847...
  • Page 471 Requests from the master must have the following format: 1 byte Slave Address 1 byte Function Code (04h) 2 bytes Starting Register Address 2 bytes Number of Registers to Read 2 bytes CRC-16 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 472 CRC-16 Table E.14 lists the coil numbers supported by the SEL-751A. The physical coils (coils 1–27) are self-resetting. Pulsing a Set remote bit (decimal address 59 through 99) causes the remote bit to be cleared at the end of the pulse.
  • Page 473 Modbus RTU Communications E.11 Communications Protocol Table E.14 01h, 05h SEL-751A Output (Sheet 2 of 4) Coil Address (Decimal) Function Code Supported Coil Description 01, 05 Pulse OUT304 1 second 01, 05 Reserved 01, 05 Reserved 01, 05 Reserved 01, 05...
  • Page 474 E.12 Modbus RTU Communications Communications Protocol Table E.14 01h, 05h SEL-751A Output (Sheet 3 of 4) Coil Address (Decimal) Function Code Supported Coil Description 01, 05 RB14 01, 05 RB15 01, 05 RB16 01, 05 RB17 01, 05 RB18 01, 05...
  • Page 475 Format Error Illegal Data Value (03h) Bad Packet Format 06h Preset Single The SEL-751A uses this function to allow a Modbus master to write directly to a database register. Refer to the Modbus Register Map in Table E.32 for a Register Command list of registers that can be written by using this function code.
  • Page 476 CRC-16 A successful response from the slave will have the following format: 1 byte Slave Address 1 byte Function Code (10h) 2 bytes Starting Address 2 bytes Number of Registers 2 bytes CRC-16 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 477 Invalid register data value Illegal Data Value (03h) Illegal Write 60h Read Parameter The SEL-751A uses this function to allow a Modbus master to read parameter information from the relay. One parameter (setting) is read in each query. Information Command Table E.20 60h Read Parameter Information Command...
  • Page 478 The relay response to errors in the query are shown Table E.23. Table E.23 Responses to 60h Read Parameter Information Query Errors Communication Error Error Code Returned Counter Increments Illegal parameter to read Illegal Address (02h) Invalid Address SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 479 E.17 Communications Protocol 61h Read Parameter The SEL-751A uses this function to allow a Modbus master to read parameter text from the relay. One parameter text (setting name) is read in each query. Text Command Table E.24 61h Read Parameter Text Command...
  • Page 480 Illegal Data Value (03h) Illegal Register 7Dh Encapsulated The SEL-751A uses this function to allow a Modbus master to perform control operations and another Modbus function with one query. The Device Packet With Control Net card will transmit this command periodically to achieve high-speed I/O...
  • Page 481 Use the 60h, 61h, and 62h commands to retrieve parameter information, and use the 03 command to retrieve values. Modifying Relay The SEL-751A does not provide password protection. It is assumed that because the interface is a binary protocol with CRC-16 protection, the Settings Using interface is being handled by an intelligent master system.
  • Page 482 Parameters such as date and time can be changed with the appropriate registers by using Modbus Function Code 06h or 10h. Controlling Output The SEL-751A includes registers for controlling some of the outputs. See LOGIC COMMAND (2000h), RESET COMMAND (2001h), and registers in Contacts Using the Reset Settings region for the control features supported by the relay.
  • Page 483 IN_MAG RES_711 IBX_S IGN_Y KW3N_D IN_ANG RTDWDGMX IBXMN VABMX KW3NMO IG_MAG RTDBRGMX IBX_H VABX_S KW3N_Y IG_ANG RTDAMB IBX_D VABXMN KVAR3PMX RTDOTHMX IBXMO VABX_H KVR3X_S RES_661 RTD1 IBX_Y VABX_D KVR3XMN RTD2 IBMN VABXMO KVR3X_H Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 484 AI304NMN RTD1NMO RTD5N_H 1038 RTD9N_S 1092 AI301XMO 1146 AI304N_H RTD1N_Y RTD5N_D 1039 RTD9NMN 1093 AI301X_Y 1147 AI304N_D RTD2MX RTD5NMO 1040 RTD9N_H 1094 AI301MNH 1148 AI304NMO RTD2X_S RTD5N_Y 1041 RTD9N_D 1095 AI301MNL 1149 AI304N_Y SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 485 AI502X_H 1416 AI505N_S 1201 AI308XMN 1255 AI403MNL 1309 AI406N_Y 1363 AI502X_D 1417 AI505NMN 1202 AI308X_H 1256 AI403N_S 1310 AI407MXH 1364 AI502XMO 1418 AI505N_H 1203 AI308X_D 1257 AI403NMN 1311 AI407MXL 1365 AI502X_Y 1419 AI505N_D Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 486 1632 SC22 1686 RES_1686 1471 MXMN_RMN 1525 AI501H 1579 MV17H 1633 SC23 1687 RES_1687 1472 MXMN_R_H 1526 AI501L 1580 MV17L 1634 SC24 1688 RES_1688 1473 MXMN_R_D 1527 AI502H 1581 MV18H 1635 SC25 1689 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 487 ROW_96 1740 RES_1740 1794 ILLFUNC 1848 ROW_43 1902 ROW_97 1741 RES_1741 1795 ILLREG 1849 ROW_44 1903 ROW_98 1742 RES_1742 1796 ILLWR 1850 ROW_45 1904 ROW_99 1743 RES_1743 1797 BADPKTF 1851 ROW_46 1905 ROW_100 Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 488: Modbus Register Map

    To use Modbus to download history data, write the event number (1–5) to the EVENT LOG SEL register at address 1747. Then read the history of the specific event number you requested from the registers shown in the Historical...
  • Page 489 292 (R/W) MAXP OC L3 DLY 0.01 293 (R/W) MAXP OC L4 EN 0 = N 1 = Y 294 (R/W) MAXP OC TRIP L4 10000 1000 0.01 295 (R/W) MAXP OC L4 DLY 0.01 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 490 0 = N 1 = Y 322 (R/W) RES OC TRIP L4 10000 0.01 323 (R/W) RES OC L4 DLY 0.01 Negative-Sequence Overcurrent 324 (R/W) NSEQ OC L1 EN 0 = N 1 = Y SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 491 5 = C1 6 = C2 7 = C3 8 = C4 9 = C5 346 (R/W) PHB TOC TIM DIAL 1500 0.01 347 (R/W) PHB EM RST DLAY 0 = N 1 = Y Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 492 1 = Y 362 (R/W) CONST TIME1 0.01 363 (R/W) MIN RESP TIME1 0.01 364 (R/W) TOC TRIP L2 EN 0 = N 1 = Y 365 (R/W) TOC TRIP LVL2 1600 0.01 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 493 371 (R/W) NSTOC TRIP EN 0 = N 1 = Y 372 (R/W) NSTOC TRIP LVL 1600 0.01 373 (R/W) NSTOC CURVE SEL 0 = U1 1 = U2 2 = U3 3 = U4 4 = U5 5 = C1...
  • Page 494 398 (R/W) RES EM RST DLAY1 0 = N 1 = Y 399 (R/W) RES CONST TIME1 0.01 400 (R/W) RES MIN RESP T1 0.01 401 (R/W) RES TOC L2 EN 0 = N 1 = Y SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 495 417 (R/W) RTD2 TYPE 0 = PT100 1 = NI100 2 = NI120 3 = CU10 418 (R/W) RTD2 TRIP LEVEL degC 0 = Off 419 (R/W) RTD2 WARN LEVEL degC 0 = Off Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 496 2 = BRG 3 = AMB 4 = OTH 433 (R/W) RTD6 TYPE 0 = PT100 1 = NI100 2 = NI120 3 = CU10 434 (R/W) RTD6 TRIP LEVEL degC 0 = Off SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 497 448 (R/W) RTD10 LOCATION 0 = OFF 1 = WDG 2 = BRG 3 = AMB 4 = OTH 449 (R/W) RTD10 TYPE 0 = PT100 1 = NI100 2 = NI120 3 = CU10 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 498 465 (R/W) UV TRIP2 ENABLE 0 = N 1 = Y 466 (R/W) UV TRIP2 LEVEL xVnm 0.01 467 (R/W) UV TRIP2 DELAY 1200 468 (R/W) UVS LVL1 ENABLE 0 = N 1 = Y SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 499 496 (R/W) RST FROM RECL-F 0.01 497 (R/W) RST FROM LO-I 3000 498 (R/W) RST FROM LO-F 0.01 499 (R/W) RECLS SUPV EN 500 (R/W) RECL SUPV TIME-I 3000 501 (R/W) RECL SUPV TIME-F 0.01 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 500 0 = N 1 = Y 526 (R/W) VS WINDOW LOW 30000 10500 0.01 527 (R/W) VS WINDOW HIGH 30000 13000 0.01 528 (R/W) MAX SLIP FREQ 0.001 529 (R/W) MAX ANGLE 1 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 501 558 (R/W) OUT401 FAIL-SAFE 559 (R/W) OUT402 FAIL-SAFE 560 (R/W) OUT403 FAIL-SAFE 561 (R/W) OUT404 FAIL-SAFE 562 (R/W) OUT501 FAIL-SAFE 563 (R/W) OUT502 FAIL-SAFE 564 (R/W) OUT503 FAIL-SAFE 565 (R/W) OUT504 FAIL-SAFE 566–570 (R) Reserved 666–670 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 502 Bit 9 = Rst Peak Demand Bit 10–15 = Reserved 592–601 (R) Reserved 692–701 Date/Time Settings 602 (R/W) SET SEC 5999 0.01 603 (R/W) SET MIN 604 (R/W) SET HOUR 605 (R/W) SET DAY SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 503 637 (R) VC STATUS 638 (R) RELAY STATUS 0 = ENABLED 1 = DISABLED 639 (R) VS STATUS 640 (R) SERIAL NUMBER H 65535 641 (R) SERIAL NUMBER L 65535 642–649 (R) Reserved 742–749 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 504 65535 683 (R) NEG-SEQ VOLT 3V2 65535 684 (R) VOLTAGE IMBAL 1000 Power Data 685 (R) REAL POWER –32768 32767 686 (R) REACTIVE POWER kVAR –32768 32767 687 (R) APPARENT POWER –32768 32767 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 505 LS 4 1000 733–738 (R) Reserved 833–838 RMS Data 739 (R) VS RMS 65535 740 (R) IA RMS 65535 741 (R) IB RMS 65535 742 (R) IC RMS 65535 743 (R) IN RMS 65535 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 506 IC MAX TIME mm 781 (R) IC MAX TIME hh 782 (R) IC MAX DAY dd 783 (R) IC MAX DAY mm 784 (R) IC MAX DAY yy 2000 9999 2000 785 (R) IC MIN 65535 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 507 824 (R) VAB/VA MX DAY dd 825 (R) VAB/VA MX DAY mm 826 (R) VAB/VA MX DAY yy 2000 9999 2000 827 (R) VAB/VA MIN 65535 828 (R) VAB/VA MN TIM ss 5999 0.01 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 508 KW3P MX DAY mm 868 (R) KW3P MX DAY yy 2000 9999 2000 869 (R) KW3P MIN –32768 32767 870 (R) KW3P MN TIM ss 5999 0.01 871 (R) KW3P MN TIM mm SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 509 9999 2000 1010 911 (R) FREQ MIN 65535 0.01 1011 912 (R) FREQ MN TIM ss 5999 0.01 1012 913 (R) FREQ MN TIM mm 1013 914 (R) FREQ MN TIM hh 1014 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 510 2000 1052 953 (R) RTD3 MIN degC –32768 32767 1053 954 (R) RTD3 MN TIM ss 5999 0.01 1054 955 (R) RTD3 MN TIM mm 1055 956 (R) RTD3 MN TIM hh 1056 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 511 –32768 32767 1095 996 (R) RTD6 MN TIM ss 5999 0.01 1096 997 (R) RTD6 MN TIM mm 1097 998 (R) RTD6 MN TIM hh 1098 999 (R) RTD6 MN DAY dd 1099 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 512 RTD9 MN TIM ss 5999 0.01 1138 1039 (R) RTD9 MN TIM mm 1139 1040 (R) RTD9 MN TIM hh 1140 1041 (R) RTD9 MN DAY dd 1141 1042 (R) RTD9 MN DAY mm 1142 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 513 –32768 32767 1179 1080 (R) RTD12 MN TIM ss 5999 0.01 1180 1081 (R) RTD12 MN TIM mm 1181 1082 (R) RTD12 MN TIM hh 1182 1083 (R) RTD12 MN DAY dd 1183 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 514 AI303 MX TIM ss 5999 0.01 1220 1121 (R) AI303 MX TIM mm 1221 1122 (R) AI303 MX TIM hh 1222 1123 (R) AI303 MX DAY dd 1223 1124 (R) AI303 MX DAY mm 1224 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 515 AI305 MN TIM mm 1261 1162 (R) AI305 MN TIM hh 1262 1163 (R) AI305 MN DAY dd 1263 1164 (R) AI305 MN DAY mm 1264 1165 (R) AI305 MN DAY yy 2000 9999 2000 1265 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 516 AI308 MX TIM mm 1301 1202 (R) AI308 MX TIM hh 1302 1203 (R) AI308 MX DAY dd 1303 1204 (R) AI308 MX DAY mm 1304 1205 (R) AI308 MX DAY yy 2000 9999 2000 1305 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 517 AI402 MN TIM mm 1341 1242 (R) AI402 MN TIM hh 1342 1243 (R) AI402 MN DAY dd 1343 1244 (R) AI402 MN DAY mm 1344 1245 (R) AI402 MN DAY yy 2000 9999 2000 1345 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 518 AI405 MX TIM mm 1381 1282 (R) AI405 MX TIM hh 1382 1283 (R) AI405 MX DAY dd 1383 1284 (R) AI405 MX DAY mm 1384 1285 (R) AI405 MX DAY yy 2000 9999 2000 1385 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 519 AI407 MN TIM mm 1421 1322 (R) AI407 MN TIM hh 1422 1323 (R) AI407 MN DAY dd 1423 1324 (R) AI407 MN DAY mm 1424 1325 (R) AI407 MN DAY yy 2000 9999 2000 1425 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 520 AI502 MX TIM mm 1461 1362 (R) AI502 MX TIM hh 1462 1363 (R) AI502 MX DAY dd 1463 1364 (R) AI502 MX DAY mm 1464 1365 (R) AI502 MX DAY yy 2000 9999 2000 1465 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 521 AI504 MN TIM mm 1501 1402 (R) AI504 MN TIM hh 1502 1403 (R) AI504 MN DAY dd 1503 1404 (R) AI504 MN DAY mm 1504 1405 (R) AI504 MN DAY yy 2000 9999 2000 1505 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 522 AI507 MX TIM mm 1541 1442 (R) AI507 MX TIM hh 1542 1443 (R) AI507 MX DAY dd 1543 1444 (R) AI507 MX DAY mm 1544 1445 (R) AI507 MX DAY yy 2000 9999 2000 1545 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 523 1489 (R) C REAL POWER –32768 32767 1589 1490 (R) C REACTIVE POWER kVAR –32768 32767 1590 1491 (R) C APPARENT POWER –32768 32767 1591 1492 (R) C POWER FACTOR -100 0.01 1592 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 524 AI503–LO –32768 32767 0.001 1630 1531 (R) AI504–HI –32768 32767 0.001 1631 1532 (R) AI504–LO –32768 32767 0.001 1632 1533 (R) AI505–HI –32768 32767 0.001 1633 1534 (R) AI505–LO –32768 32767 0.001 1634 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 525 MV16–HI –32768 32767 0.01 1677 1578 (R) MV16–LO –32768 32767 0.01 1678 1579 (R) MV17–HI –32768 32767 0.01 1679 1580 (R) MV17–LO –32768 32767 0.01 1680 1581 (R) MV18–HI –32768 32767 0.01 1681 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 526 EXT TRIPS 65535 1749 1650 (R) IA RLY 65535 1750 1651 (R) IA EXT 65535 1751 1652 (R) IB RLY 65535 1752 1653 (R) IB EXT 65535 1753 1654 (R) IC RLY 65535 1754 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 527 3I2 PEAK DEMAND 65535 1798 1699 (R) PEAKD RST TIM ss 5999 0.01 1799 1700 (R) PEAKD RST TIM mm 1800 1701 (R) PEAKD RST TIM hh 1801 1702 (R) PEAKD RST DAT dd 1802 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 528 1705-1718 (R) Reserved 1805-1818 Reserved Area 5 1719–1745 (R) Reserved 1819–1845 Historical Data 1746 (R) NO. EVENT LOGS 1846 1747 (R/W) EVENT LOG SEL. 1847 1748 (R) EVENT TIME ss 5999 0.01 1848 1749 (R) EVENT TIME mm 1849 1750 (R)
  • Page 529 1771 (R) EVNT MAX BRG RTD degC –32768 32767 1871 1772 (R) EVNT MAX AMB RTD degC –32768 32767 1872 1773 (R) EVNT MAX OTH RTD degC –32768 32767 1873 1774–1779 (R) Reserved 1874–1879 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 530 Bit 9 = NEG SEQ 50Q2 Bit 10 = NEG SEQ 50Q3 Bit 11 = NEG SEQ 50Q4 Bit 12 = PHASE 51P2 Bit 13 = GROUND 51G2 Bit 14 = NEUTRAL 51N2 Bit 15 = RESERVED SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 531 1906 Bit 0 = 52A Bit 1 = * Bit 2 = ORED51T Bit 3 = ORDE50T Bit 4 = * Bit 5 = 50C1P Bit 6 = 50B1P Bit 7 = 50A1P Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 532 1912 Bit 0 = 51QT Bit 1 = 51N2T Bit 2 = 51N1T Bit 3 = 51P2T Bit 4 = 51P1T Bit 5 = 51CT Bit 6 = 51BT Bit 7 = 51AT SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 533 1918 Bit 0 = FAULT Bit 1 = IRIGOK Bit 2 = TSOK Bit 3 = WARNING Bit 4 = SALARM Bit 5 = PMDOK Bit 6 = LINKB Bit 7 = LINKA Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 534 1959 (R/W) AF PH OC TRP LVL 10000 0.01 2059 1960 (R/W) ENBL AF N OC 2060 0 = N 1 = Y 1961 (R/W) AF N OC TRP LVL 10000 0.01 2061 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 535 0 = N 1 = Y 1980 (R/W) CTRL BITS DEFN 2080 0 = NONE 1 = C37.118 1981 (R/W) IRIG TIME SOURCE 2081 0 = IRIG1 1 = IRIG2 1982-1991 (R) Reserved 2082-2091 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 536 2017 (R/W) 81R1 TRIP DELAY 6000 0.01 2117 2018 (R/W) 81R1 DO DELAY 6000 0.01 2118 2019 (R/W) ENABLE 81R2 2119 0 = N 1 = Y 2020 (R/W) 81R2 TRIP LEVEL Hz/s 1500 1500 0.01 2120 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 537 2041 (R/W) 3PH PWR ELEM PU 65000 20000 2141 2042 (R/W) PWR ELEM TYPE 2142 0 = + WATTS 1 = – WATTS 2 = + VARS 3 = –VARS 2043 (R/W) PWR ELEM DELAY 2400 2143 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 538 Bit 4 = Reset Comm Cntr Bit 5 = Reserved Bit 6 = Rst Enrgy Data Bit 7 = Rst Mx/Mn Data Bit 8 = Rst Demand Bit 9 = Rst Peak Demand Bit 10–15 = Reserved SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 539 IA CURRENT 2108H (R) IB CURRENT 2109H (R) IC CURRENT 210AH (R) Reserved 210BH (R) CURRENT IMBAL 210CH (R) MAX WINDING RTD 210DH (R) IG CURRENT 210EH (R) IN CURRENT 210FH (R) Reserved Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 540 DC BATTERY MONITOR 3008H (R) CONFIG SETTINGS 3009H (R) MAX PH OVERCURR 300AH (R) NEUTRAL OVERCURR 300BH (R) RESIDUAL OVERCUR 300CH (R) NEG SEQ OVERCURR 300DH (R) PHASE TOC 300EH (R) MAXIMUM PH TOC SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 541 HISTORICAL DATA 1746 1779 1746 3038H (R) TRIP/WARN DATA 1780 1788 1780 3039H (R) COMMN COUNTERS 1789 1804 1789 303AH (R) RELAY ELEMENTS 1805 1947 1805 303BH (R) EXTRA SETTINGS 1948 2070 1948 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 542 Name/Enums Units Default Parameter Address Factor Numbers Product Information 4000H (R) VENDOR CODE 65535 865 = SEL 4001H (R) PRODDUCT CODE 65535 4002H (R/W) ASA NUMBER LOW 65535 4003H (R/W) ASA NUMBER HIGH 65535 4004H (R) FIRMWARE REVISION 32639 4005H (R)
  • Page 543 All addresses in this table refer to the register addresses in the Modbus packet. Registers labeled (R/(W) are read-write registers. Registers labeled (W) are write-only registers. Registers Labeled (R) are read-only registers. Reserved addresses return 0. Date Code 20100129 Instruction Manual SEL-751A Relay...
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  • Page 545: Features

    Appendix F IEC 61850 Communications Features The SEL-751A relay supports the following features using Ethernet and IEC 61850: SCADA. Use as many as six MMS sessions of buffered and unbuffered reports. Remote bits (RB01–RB32) are mapped to the RBGGIO logical node. Breaker control bits (CC and OC) are mapped to the BKR1CSWI1 logical node.

  • Page 546: Introduction To Iec 61850

    The IEC 61850 document set, available directly from the IEC at http://www.iec.ch, contains information necessary for successful implementation of this protocol. SEL strongly recommends that anyone involved with the design, installation, configuration, or maintenance of IEC 61850 systems be familiar with the appropriate sections of these documents.

  • Page 547: Iec 61850 Operation

    IEC 61850 Operation Ethernet Networking IEC 61850 and Ethernet networking are available as options in the SEL-751A. In addition to IEC 61850, the Ethernet port provides support protocols and data exchange, including FTP and Telnet. Access the SEL-751A Port 1 settings to configure all of the Ethernet settings, including IEC 61850 network settings.
  • Page 548 Device data is mapped to IEC 61850 logical nodes (LN) according to rules defined by SEL. Refer to IEC 61850-5:2003(E) and IEC 61850-7-4:2003(E) for the mandatory content and usage of these LNs. The SEL-751A logical nodes are grouped under Logical Devices for organization based on function.
  • Page 549 This information can be useful when searching through device data with MMS browsers. If you intend to use any SEL-751A virtual bits for controls, you must create SEL equations to define these operations.
  • Page 550 IEC 61850 Communications IEC 61850 Operation Figure F.1 SEL-751A Predefined Reports There are 12 report control blocks, six buffered reports and six unbuffered. For each report control block, there can be just one client association, i.e., only one client can be associated to a report control block (BRCB or URCB) at any given time.
  • Page 551 URCB at a time, resulting in multiple client associations for that URCB. Once enabled, each client has independent access to a copy of that URCB. The Resv attribute is writable, however, the SEL-751A does not support reservations. Writing any field of the URCB causes the client to obtain their own copy of the URCB-in essence, acquiring a reservation.
  • Page 552 Examine the data structure and value of the supported IEC 61850 LNs with an MMS browser such as MMS Object Explorer and AX-S4 MMS from Sisco, Software Inc. The settings needed to browse an SEL-751A with an MMS browser are shown below: OSI-PSEL (Presentation Selector) 00000001...
  • Page 553 For example, if the device becomes disabled, as shown via status indications (e.g., an internal self-test failure), the SEL-751A will set the Validity attribute to invalid and the Failure attribute to TRUE. Note that the SEL-751A does not set any of the other quality attributes. These attributes will always indicate FALSE (0).

  • Page 554: Iec 61850 Configuration

    Incoming GOOSE messages are processed in accordance with the following constraints: ➤ The user can configure the SEL-751A to subscribe to as many as 16 incoming GOOSE messages. The SEL-751A will recognize incoming GOOSE messages as valid based on the following content. Any GOOSE message that fails these checks shall be rejected.
  • Page 555 IEDs in the domain. Architect has the ERATOR capability to read other manufacturer's ICD and CID files, enabling the engineer to map the data seamlessly into SEL IED logic. See the Architect Instruction Manual or online help for more ERATOR information.
  • Page 556 002 R200 or greater: Constrained Logical Node names as above, with additional logical nodes made accessible in SEL-751A R200 or higher firmware. Select this file to enable access to these additional logical nodes. Note: Using this file with SEL-751A firmware versions lower than R200 may cause unexpected behavior.
  • Page 557 D3T_PTOF3 D3TPTOF3 D3TPTOF3 D3TPTOF3 Definite-time over- and underfre- quency element 3 D4T_PTOF4 D4TPTOF4 D4TPTOF4 D4TPTOF4 Definite-time over- and underfre- quency element 4 — — — D5TPTOF5 Definite-time over- and underfre- quency element 5 Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 558 Power factor trip TRIP_PTRC1 TRIPPTRC1 TRIPPTRC1 TRIPPTRC1 Output of trip logic ULTRIP_PTRC2 ULTRIPPTRC2 — — Unlatch trip (auto reset) from SEL- control equation (not supported OGIC in firmware versions R200 or higher) — — — BFR1RBRF1 Breaker Failure Element BK1_XCBR1...
  • Page 559 — AINDGGIO22 AINDGGIO22 Analog Inputs 401 to 408 (supported only in firmware versions R200 or higher) — — AINEGGIO23 AINEGGIO23 Analog Inputs 501 to 508 (supported only in firmware versions R200 or higher) Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 560: Logical Node Extensions

    Tmp02 Temperature 2 Tmp03 Temperature 3 Tmp04 Temperature 4 Tmp05 Temperature 5 Tmp06 Temperature 6 Tmp07 Temperature 7 Tmp08 Temperature 8 Tmp09 Temperature 9 Tmp10 Temperature 10 Tmp11 Temperature 11 Tmp12 Temperature 12 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 561 Reactive energy supply (default supply direction: energy flow towards busbar) DmdWh Real energy demand (default demand direction: energy flow from busbar away) DmdVArh Reactive energy demand (default demand direction: energy flow from busbar away) Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 562: Logical Nodes

    The following tables, Table F.12 through Table F.15, show the Logical Nodes (LN) supported in the SEL-751A and the associated Relay Word bits or measured quantities. Table F.12 shows the LN associated with protection elements defined as Logical Device PRO.
  • Page 563 D5TPTOF5 Str.general 81D5T D5TPTOF5 Op.general 81D5T D6TPTOF6 Str.general 81D6T D6TPTOF6 Op.general 81D6T R1TPFRC1 Str.general 81R1T R1TPFRC1 Op.general 81R1T R2TPFRC2 Str.general 81R2T R2TPFRC2 Op.general 81R2T R3TPFRC3 Str.general 81R3T R3TPFRC3 Op.general 81R3T R4TPFRC4 Str.general 81R4T Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 564 Op.general T55POPF2 Str.general T55POPF2 Op.general TRIPPTRC1 Tr.general TRIP BFR1RBRF1 Str.general BFR1RBRF1 OpEx.general BK1XCBR1 Pos.stVal Result of 52A SEL setting OGIC BK1XCBR1 OpCnt.stVal INTT Internal Trips Counter BKR1CSWI1 Pos.stVal Result of 52A SEL setting OGIC SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 565 A.res.cVal.mag Residual current magnitude METMMXU1 A.res.cVal.ang Residual current angle METMMXU1 W.phsA.mag A-phase real power magnitude METMMXU1 W.phsB.mag B-phase real power magnitude METMMXU1 W.phsC.mag C-phase real power magnitude METMMXU1 VAr.phsA.mag A-phase reactive power magnitude Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 566 B-phase current minimum magnitude METMSTA1 MinA.phsC.mag C-phase current minimum magnitude METMSTA1 MinA.neut.mag Neutral current minimum magnitude METMSTA1 MinA.res.mag Residual current minimum magnitude METMSTA1 AvVolts.mag Average voltage magnitude METMSTA1 MaxPhV.phsA.mag A-phase voltage maximum magnitude SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 567 Valid data only if either PT card (AVI) or differential PT/CT card (3AVI/3ACI) is installed. Valid data depends on E49RTD and RTD1LOC—RTD12LOC settings. Valid data only if a premium voltage option card (5AVI or 3 AVI/4 AFDI) is installed. Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 568 Active data depends on the ESC setting. Active data only if an I/O card is installed in the slot. Active data depends on the ESV setting. Active data depends on the ELT setting. SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 569: Protocol Implementation Conformance Statement

    IEC 61850 Protocol services. Table F.18 defines the service support requirement and restrictions of the MMS services in the SEL-700 series products supporting IEC 61850. Generally, only those services whose implementation is not mandatory are shown. Refer to the IEC 61850 standard Part 8-1 for more information.
  • Page 570 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 571 ReconfigureProgramInvocation Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 572 Table F.20 Alternate Access Selection Conformance Statement Alternate Access Selection Client-CR Supported Server-CR Supported accessSelection component index indexRange allElements alternateAccess selectAccess component index indexRange allElements Table F.21 VariableAccessSpecification Conformance Statement VariableAccessSpecification Client-CR Supported Server-CR Supported listOfVariable variableSpecification alternateAccess variableListName SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 573 Table F.24 GetVariableAccessAttributes Conformance Statement GetVariableAccessAttributes Client-CR Supported Server-CR Supported Request name address Response mmsDeletable address typeSpecification Table F.25 DefineNamedVariableList Conformance Statement DefineVariableAccessAttributes Client-CR Supported Server-CR Supported Request variableListName listOfVariable variableSpecification alternateAccess Response Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 574 Server-CR Supported Request Scope listOfVariableListName domainName Response numberMatched numberDeleted DeleteNamedVariableList-Error GOOSE Services Table F.28 GOOSE Conformance Conformance Subscriber Publisher Value/Comment Statement GOOSE Services SendGOOSEMessage GetGoReference GetGOOSEElementNumber GetGoCBValues SetGoCBValues GSENotSupported GOOSE Control Block (GoCB) SEL-751A Relay Instruction Manual Date Code 20100129...

  • Page 575: Acsi Conformance Statements

    IEC 61850 Communications F.31 ACSI Conformance Statements ACSI Conformance Statements Table F.29 ACSI Basic Conformance Statement Client/Subscriber Server/Publisher SEL-751A Support Client-Server Roles Server side (of Two-Party Applica- tion-Association) Client side (of Two-Party Applica- tion-Association) SCMS Supported SCSM: IEC 61850-8-1 used...
  • Page 576 F.32 IEC 61850 Communications ACSI Conformance Statements Table F.30 ACSI Models Conformance Statement (Sheet 2 of 2) Client/Subscriber Server/Publisher SEL-751A Support Unbuffered report control M8-1 sequence-number M8-2 report-time-stamp M8-3 reason-for-inclusion M8-4 data-set-name M8-5 data-reference M8-6 BufTm M8-7 IntgPd M-8-8 Logging...
  • Page 577 IEC 61850 Communications F.33 ACSI Conformance Statements Table F.31 ACSI Services Conformance Statement (Sheet 2 of 4) Client/ Service/ Services AA: TP/MC SEL-751A Support Subscriber Publisher Logical Node (Clause 9) LogicalNodeDirectory GetAllDataValues Data (Clause 10) GetDataValues SetDataValues GetDataDirectory GetDataDefinition Data Set (Clause 11)
  • Page 578 F.34 IEC 61850 Communications ACSI Conformance Statements Table F.31 ACSI Services Conformance Statement (Sheet 3 of 4) Client/ Service/ Services AA: TP/MC SEL-751A Support Subscriber Publisher Logging (Clause 14) Log Control Block GetLCBValues SetLCBValues QueryLogByTime QueryLogByEntry GetLogStatusValues Generic Substation Event Model (GSE) (Clause 14.3.5.3.4)
  • Page 579 IEC 61850 Communications F.35 ACSI Conformance Statements Table F.31 ACSI Services Conformance Statement (Sheet 4 of 4) Client/ Service/ Services AA: TP/MC SEL-751A Support Subscriber Publisher File Transfer (Clause 20) GetFile SetFile DeleteFile GetFileAttributeValues Time (Clause 5.5) Time resolution of internal...
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  • Page 581 DeviceNet card. DeviceNet Card The DeviceNet Card is an optional accessory that enables connection of the SEL-751A to the DeviceNet automation network. The card (see Figure G.1) occupies the communications expansion Slot C in the relay.
  • Page 582 ➤ Rotary switches let you set the node address and network data rate prior to mounting in the SEL-751A and applying power. Alternatively, the switches can be set to positions that allow for configuration of these settings over the DeviceNet network, utilizing a network configuration tool such as RSNetWorx for DeviceNet.

  • Page 583: Electronic Data Sheet

    The EDS file for the SEL-751A, SEL-xxxRxxx.EDS, is located on the SEL-751A Product Literature CD, or can also be downloaded from the SEL website at www.selinc.com. Complete specifications for the DeviceNet protocol are available on the Open DeviceNet Vendor’s Association (ODVA) website www.odva.org.
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  • Page 585 The value of synchrophasor data increases greatly when the data can be shared over a communications network in real time. A synchrophasor protocol is available in the SEL-751A that allows for a centralized device to collect data efficiently from several phasor measurement units (PMUs). Some possible uses of a system-wide synchrophasor system include the following: ➤...
  • Page 586 10:00:00:000000 10:00:00:016667 Figure H.1 Phase Reference The TSOK Relay Word bit asserts when the SEL-751A has determined that the IRIG-B time source has sufficient accuracy and the synchrophasor data meets the specified accuracy. Synchrophasors are still measured if the time source threshold is not met, as indicated by Relay Word bit TSOK = logical 0.
  • Page 587 In other words, a power system has a nominal frequency of either 50 or 60 Hz, but on closer examination, it is usually running a little faster or slower than nominal. Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 588: Settings For Synchrophasors

    It is possible to set EPMU := Y without using any serial ports for synchrophasor protocols. For example, the serial port MET PM ASCII command can still be used. Table H.1 PMU Settings in the SEL-751A for C37.118 Protocol in Global Settings Setting...
  • Page 589 PROTO setting to PMU, you will lose the ability to communicate with the relay through ASCII commands or virtual file interface commands. If this happens, either connect via another serial port (that has PROTO := SEL) or use the front-panel HMI SET/SHOW screen to change the disabled port PROTO setting back to SEL.
  • Page 590 Magnitude Angle PHDATAV := V1 or ALL PHDATAV := ALL PHDATAI := I1 or ALL PHDATAI := ALL Synchrophasors are included in the order shown (i.e., voltages, if selected, will always precede currents). SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 591 Table H.5. Table H.5 User-Defined Digital Status Words Selected by the NUMDSW Setting Total Number of Bytes NUMDSW Setting Digital Status Words Sent Used for Digital Values None [SV32, SV31..SV17] Date Code 20100129 Instruction Manual SEL-751A Relay...

  • Page 592: Synchrophasor Relay Word Bits

    Global OGIC settings class. The SEL-751A evaluates these equations and places the results in Relay Word bits with the same names: TREA1–TREA4, and PMTRIG. The trigger reason equations represent the Trigger Reason bits in the STAT...

  • Page 593: View Synchrophasors Using The Met Pm Command

    PHCURR. The MET PM command can function even when no serial ports are sending synchrophasor data—it is unaffected by serial port setting PROTO. The MET PM command will only operate when the SEL-751A is in the IRIG timekeeping mode, as indicated by Relay Word bit TSOK = logical 1. Figure H.4 shows a sample MET PM command response.

  • Page 594: C37.118 Synchrophasor Protocol

    Global setting NUMANA, and 0 or 16 digital status values, as controlled by Global setting NUMDSW. The SEL-751A always includes the results of four synchrophasor trigger reason SEL equations TREA1, TREA2, TREA3, and TREA4, and the...
  • Page 595 The SEL-751A will only transmit synchrophasor messages over serial ports that have setting PROTO := PMU. The connected device will typically be a synchrophasor processor, such as the SEL-3306. The synchrophasor processor controls the PMU functions of the SEL-751A, with IEEE C37.118 commands, Date Code 20100129 Instruction Manual...
  • Page 596 Transmit Mode Control The SEL-751A will not begin transmitting synchrophasors until an enable message is received from the synchrophasor processor. The relay will stop synchrophasor transmission when the appropriate command is received from the synchrophasor processor.
  • Page 597 IRRORED rates at and above 9600 baud the SEL-751A self-paces, using a technique similar to the SEL-400 series pacing mode. There are no settings to enable or disable the self-pacing mode; the SEL-751A automatically enters the self- pacing mode at baud rates of 9600, 19200, and 38400.
  • Page 598 RMBnA and RMBnB relay element bits. Message Decoding Set the RX_ID of the local SEL-751A to match the TX_ID of the remote SEL-751A. The SEL-751A provides indication of the status of each and Integrity Checks...
  • Page 599 1/4-cycle processing interval (9600 baud and above, see Table I.1), a counter set to two in the SEL-321 delays a received bit by another approximately 1/2 cycle. However, a security counter in the SEL-751A with a setting of two delays a received bit from the SEL-321 by 1/4 cycle, because...
  • Page 600 Use the RBADPU setting to determine how long a channel error must last before the meter element RBADA is asserted. RBADA is deasserted when the channel error is corrected. RBADPU is accurate to ±1 second. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 601 CBADPU Channel Unavailability to Set CBAD (1–10000 ppm) 1000 RXDFLT 8 char string of 1s, 0s, or Xs XXXXXXXX RMB1PU RMB1 Pickup Debounce Messages (1–8 messages) RMB1DO RMB1 Dropout Debounce Messages (1–8 messages) Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 602 RMB6 Dropout Debounce Messages (1–8 messages) RMB7PU RMB7 Pickup Debounce Messages (1–8 messages) RMB7DO RMB7 Dropout Debounce Messages (1–8 messages) RMB8PU RMB8 Pickup Debounce Messages (1–8 messages) RMB8DO RMB8 Dropout Debounce Messages (1–8 messages) SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 603 Relay Word Bits Overview The protection and control element results are represented by Relay Word bits in the SEL-751A Feeder Protection Relay. Each Relay Word bit has a label name and can be in either of the following states: ➤...
  • Page 604 Relay Word Bits Overview Table J.1 SEL-751A Relay Word Bits (Sheet 2 of 4) Relay Word Bits Bit/ OUT401 OUT402 OUT403 OUT404 OUT501 OUT502 OUT503 OUT504 IN101 IN102 IN301 IN302 IN303 IN304 IN305 IN306 IN307 IN308 IN401 IN402 IN403 IN404...
  • Page 605 Relay Word Bits Overview Table J.1 SEL-751A Relay Word Bits (Sheet 3 of 4) Relay Word Bits Bit/ SC01QD SC02QD SC03QD SC04QD SC05QD SC06QD SC07QD SC08QD SC09QU SC10QU SC11QU SC12QU SC13QU SC14QU SC15QU SC16QU SC09QD SC10QD SC11QD SC12QD SC13QD SC14QD...
  • Page 606 AFS3EL AFS4EL PHASE_A PHASE_B PHASE_C GFLT Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 1 of 11) Definition Reserved for future use. — 3I2DEM Negative Sequence Demand Pickup. 3P27 3-Phase Undervoltage Trip Pickup (all phases below 27P1P setting).
  • Page 607 Relay Word Bits Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 2 of 11) Definition 25A2 Synchronism Check Element Level 2 Pickup. 27P1 Phase Undervoltage Trip 1 Pickup (see Figure 4.18). 27P1T Phase Undervoltage Trip 1 Output (see Figure 4.18).
  • Page 608 Relay Word Bits Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 3 of 11) Definition 50Q4P Definite-Time Negative-Sequence Overcurrent Trip 4 Pickup (see Figure 4.1). 50Q4T Definite-Time Negative-Sequence Overcurrent Trip 4 Output (see Figure 4.1). 51AP Phase A Time-Overcurrent Element Pickup (see Figure 4.3).
  • Page 609 Relay Word Bits Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 4 of 11) Definition 59P1 Phase Overvoltage Trip 1 Pickup (see Figure 4.19). 59P1T Phase Overvoltage Trip 1 Output (see Figure 4.19). 59P2 Phase Overvoltage Trip 2 Pickup (see Figure 4.19).
  • Page 610 Relay Word Bits Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 5 of 11) Definition AFS4EL Arc-Flash Sensor input 4 excessive ambient light pickup for 10 seconds. AIHAL Analog inputs High Alarm Limit. If any AIxxxHAL = 1, then AIHAL = 1.
  • Page 611 Relay Word Bits Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 6 of 11) Definition DNAUXn DeviceNet/Modbus AUXn assert bit, where n = 1 to 8. DNAUXn DeviceNet/Modbus AUXn assert bit, where n = 9 to 11.
  • Page 612 J.10 Relay Word Bits Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 7 of 11) Definition OTHALRM Other Temperature Alarm. Asserts when any healthy Other RTD temperature exceeds the alarm/ warning set point for that temperature. OTHTRIP Other Temperature Trip.
  • Page 613 Relay Word Bits J.11 Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 8 of 11) Definition PMDOK Phasor Measurement Data OK. Asserts when the SEL-751A is enabled and synchrophasors are enabled (Global setting EPMU:= Y) (see Table H.7).
  • Page 614 J.12 Relay Word Bits Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 9 of 11) Definition RTD7T RTD7 Trip. RTD8A RTD8 Alarm. RTD8T RTD8 Trip. RTD9A RTD9 Alarm. RTD9T RTD9 Trip. RTDFLT Asserts when an open or short circuit condition is detected on any enabled RTD input, or commu- nication with the external RTD module has been interrupted.
  • Page 615 Relay Word Bits J.13 Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 10 of 11) Definition T04_LED Asserts when the SEL control equation T04_LED result is logical 1 (see Table 4.66). OGIC T05_LED Asserts when the SEL...
  • Page 616 J.14 Relay Word Bits Definitions Table J.2 Relay Word Bit Definitions for the SEL-751A (Sheet 11 of 11) Definition WARNING Asserts when any of the protection elements (warning level) operates or when the relay detects self-test failure (see Table 10.7), RTD faults, or DeviceNet communications alarms.
  • Page 617 Appendix K Analog Quantities The SEL-751A Feeder Protection Relay contains several analog quantities that can be used for more than one function. The actual analog quantities available depend on the part number of the relay used. Analog quantities are typically generated and used by a primary function, such as, metering and selected quantities are made available for one or more supplemental functions, for example, the load profile.
  • Page 618 A-phase reactive power kVAR primary B-phase reactive power kVAR primary C-phase reactive power kVAR primary 3-phase reactive power kVAR primary VAR primary A-phase power factor B-phase power factor C-phase power factor 3-phase power factor SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 619 A primary IGMX Calculated residual maximum current A primary IAMN A-phase minimum current A primary IBMN B-phase minimum current A primary ICMN C-phase minimum current A primary INMN Neutral minimum current A primary Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 620 AI308MN AI401MX to Analog transducer input 401–408 maximum AI408MX AI401MN to Analog transducer input 401–408 minimum AI408MN AI501MX to Analog transducer input 501–508 maximum AI508MX AI501MN to Analog Transducer Input 501–508 minimum AI508MN SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 621 Accumulated current—external trips, A phase kA primary EXTIB Accumulated current—external trips, B phase kA primary EXTIC Accumulated current—external trips, C phase kA primary WEARA Breaker Wear, A-phase WEARB Breaker Wear, B-phase WEARC Breaker Wear, C-phase Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 622 MV01 to MV32 Math variable 01 to math variable 32 Counters OGIC SC01 to SC32 counter 01 to SEL counter 32 OGIC OGIC See the Engineering Unit settings (e.g., AI301EU) of the respective analog input quantity for the unit. DATE, TIME, RID, and TID are only available for display point settings (DP01 to DP32).
  • Page 623 Bare-Fiber Sensor—The fiber optic loop sensor used for arc-flash detection. Point Sensor—The fiber-optic cable sensor with a light diffuser on the end and used for arc-flash detection. Arc-Flash Protection An action performed by the relay to minimize the arc-flash hazard. (Relay) Date Code 20100129 Instruction Manual SEL-751A Relay...
  • Page 624 To activate; to fulfill the logic or electrical requirements needed to operate a device. To apply a short-circuit or closed contact to an SEL-751A input. To set a logic condition to the true state (logical 1). To close a normally-open output contact.
  • Page 625 Fundamental Meter Type of meter data presented by the SEL-751A that includes the present val- ues measured at the relay ac inputs. The word “Fundamental” is used to indi- cate that the values are Fundamental Frequency values and do not include harmonics.
  • Page 626 Power factor equals 1.0 for power flowing to a resistive load. Power, Q Reactive part of the complex power (S) expressed in units of Vars (W), kilo- vars (kVar), or megavars (MVar). SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 627 Abbreviation for Resistance Temperature Device. An RTD is made of a metal having a precisely known resistance and temperature coefficient of resistance. The SEL-751A (and the SEL-2600 RTD Module) can measure the resistance of the RTD, and thus determine the temperature at the RTD location. Typically embedded in the motor windings or attached to the races of bearings.
  • Page 628 Z-Number That portion of the relay RID string that identifies the proper ERATOR QuickSet SEL-5030 software relay driver version when creating or editing relay settings files. SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 629 .6.4 See Commands binary inputs .D.27 Synchrophasors (C37.118 protocol) ASCII Protocol binary outputs .D.27 – .H.1 .H.12 See SEL ASCII Protocol data map .D.25 Communications Cables and Automatic Messages device profile .D.20 Connections events .9.1 .9.3 DNP Map Settings .4.124...
  • Page 630 .10.12 serial port .4.108 Meter set relay .6.2 accuracy .1.24 target LEDs .8.12 Password apparent power .5.2 .5.3 timeout .8.4 – access level .7.17 .7.18 current .5.2 .5.3 .5.4 change .7.34 SEL-751A Relay Instruction Manual Date Code 20100129...
  • Page 631 .4.27 Targets trip temperatures .4.28 front-panel function .8.12 trip voting .4.28 reset targets .8.13 view using communications port .7.41 SEL ASCII Protocol .C.1 Testing acceptance testing .10.2 SEL-2600 RTD Module – failure messages .5.5 commissioning testing .10.2 .10.5 connection tests .10.5...
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  • Page 633 SEL-751A Relay Command Summary The table below lists the front serial port ASCII commands associated with particular activities. The commands are shown in uppercase letters, but they can also be entered using lowercase letters. Serial Port Command Command Description Access Level 0 Commands Go to Access Level 1.
  • Page 634 2 SEL-751A Relay Command Summary Serial Port Command Command Description HIS n Show summary of n latest event reports, where n = 1 is the most recent entry. If n is not specified, all event report summaries are displayed. HIS C or R Clear or reset history buffer.
  • Page 635 SEL-751A Relay Command Summary Serial Port Command Command Description TAR n Display target row n. TAR n k Display target row n. Repeat display of row n for repeat count k. TAR name Display the target row with target name in the row.
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  • Page 637 SEL-751A Relay Command Summary The table below lists the front serial port ASCII commands associated with particular activities. The commands are shown in uppercase letters, but they can also be entered using lowercase letters. Serial Port Command Command Description Access Level 0 Commands Go to Access Level 1.
  • Page 638 2 SEL-751A Relay Command Summary Serial Port Command Command Description HIS n Show summary of n latest event reports, where n = 1 is the most recent entry. If n is not specified, all event report summaries are displayed. HIS C or R Clear or reset history buffer.
  • Page 639 SEL-751A Relay Command Summary Serial Port Command Command Description TAR n Display target row n. TAR n k Display target row n. Repeat display of row n for repeat count k. TAR name Display the target row with target name in the row.
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