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GE P741 Technical Manual

Busbar differential protection relay
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Table Of Contents
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Table of Contents

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GE Energy Connections
Grid Solutions
MiCOM P40 Agile
P741, P742, P743
Technical Manual
Busbar Differential Protection Relay
Hardware version: J and K
Software version: 51
Publication reference: P74x/EN M/Na7

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Summary of Contents for GE P741

  • Page 1 GE Energy Connections Grid Solutions MiCOM P40 Agile P741, P742, P743 Technical Manual Busbar Differential Protection Relay Hardware version: J and K Software version: 51 Publication reference: P74x/EN M/Na7...
  • Page 3 CONTENTS Safety Section Section 1 Introduction P74x/EN IT/Na7 Section 2 Technical Data P74x/EN TD/Na7 Section 3 Getting Started P74x/EN GS/Na7 Section 4 Settings P74x/EN ST/Na7 Section 5 Operation P74x/EN OP/Na7 Section 6 Application Notes P74x/EN AP/Na7 Section 7 Programmable Logic P74x/EN PL/Na7 Section 8 Measurements and Recording...
  • Page 5 Introduction P74x/EN IT/Na7 MiCOM P741, P742, P743 INTRODUCTION Hardware Suffix: J and K Software Version:...
  • Page 6 P74x/EN IT/Na7 Introduction MiCOM P741, P742, P743...
  • Page 7 Introduction P74x/EN IT/Na7 MiCOM P741, P742, P743 (IT) 1-1 CONTENTS DOCUMENTATION STRUCTURE INTRODUCTION TO MiCOM PRODUCT SCOPE Functional overview Ordering options FIGURES FIGURE 1: FUNCTIONAL DIAGRAM...
  • Page 8 P74x/EN IT/Na7 Introduction (IT) 1-2 MiCOM P741, P742, P743...

  • Page 9: Documentation Structure

    Introduction P74x/EN IT/Na7 MiCOM P741, P742, P743 (IT) 1-3 DOCUMENTATION STRUCTURE The manual provides a functional and technical description of the MiCOM protection relay and a comprehensive set of instructions for the relay’s use and application. The section contents are summarized below:...
  • Page 10 P74x/EN IT/Na7 Introduction (IT) 1-4 MiCOM P741, P742, P743 P74x /EN SC SCADA Communications This section provides an overview regarding the SCADA communication interfaces of the relay. Detailed protocol mappings, semantics, profiles and interoperability tables are not provided within this manual. Separate documents are available per protocol, available for download from our website.
  • Page 11 Introduction P74x/EN IT/Na7 MiCOM P741, P742, P743 (IT) 1-5 INTRODUCTION TO MiCOM MiCOM is a comprehensive solution capable of meeting all electricity supply requirements. It comprises a range of components, systems and services from General Electric. Central to the MiCOM concept is flexibility.

  • Page 12: Product Scope

    P74x/EN IT/Na7 Introduction (IT) 1-6 MiCOM P741, P742, P743 PRODUCT SCOPE The P74x differential busbar protection relays have been designed for the protection of a wide range of substation busbars from distribution to transmission voltage levels. The relays include a comprehensive range of non-protection features to aid with system diagnosis and fault analysis.
  • Page 13 The P74x supports the following relay management functions in addition to the functions illustrated above. • Trip circuit and coil supervision • 4 Alternative setting groups • Programmable function keys (P741 and P743) • Control inputs • Programmable scheme logic • Programmable allocation of digital inputs and outputs •...

  • Page 14: Ordering Options

    P74x/EN IT/Na7 Introduction (IT) 1-8 MiCOM P741, P742, P743 Ordering options Information Required with Order Information Required with Order Variants Order Number P741 Busbar Protection Relay P741 Vx Aux Rating 24 - 48 Vdc 48 - 125 Vdc (40 - 100 Vac)
  • Page 15 Introduction P74x/EN IT/Na7 MiCOM P741, P742, P743 (IT) 1-9 Information Required with Order Variants Order Number P742 Busbar Protection Peripheral Unit (40TE) P742 Vx Aux Rating 24 - 54Vdc 48 - 125Vdc (40 - 100Vac) 110 - 250Vdc (100 - 240Vac)
  • Page 16 P74x/EN IT/Na7 Introduction (IT) 1-10 MiCOM P741, P742, P743 Information Required with Order Variants Order Number P743 Busbar Protection Peripheral Unit (60TE) P743 Vx Aux Rating 24 - 54Vdc 48 - 125Vdc (40 - 100Vac) 110 - 250Vdc (100 - 240Vac)
  • Page 17 Technical Data P74x/EN TD/Na7 MiCOM P741, P742, P743 TECHNICAL DATA Hardware Suffix: J and K Software Version:...
  • Page 18 P74x/EN TD/Na7 Technical Data MiCOM P741, P742, P743...
  • Page 19 Tx and one Rx. Optical budget: 5.6 dB Case Protective Earth Connection Data rate:2.5 Mbits Two rear stud connections (2 P741, 1 P742/3), Max Length: 1000 m threaded M4. Optional Rear Ethernet Connection for IEC Must be earthed (grounded) using the...
  • Page 20 Input Optical Power Nominal Burden Min. Minimum at Window –33.5 –31 avg. Quiescent burden: Edge P741: 37 to 41 W Input Optical Power Min. P742: 16 to 23 W Minimum at Eye –34.5 –31.8 avg. Center P743: 22 to 32 W...
  • Page 21 Technical Data P74x/EN TD/Na7 MiCOM P741, P742, P743 (TD) 2-5 Power Supply Interruption Operating time: Per IEC 60255-11: 1979 <200µs The relay will withstand a 20ms interruption in & Reset time: 7.5ms the DC auxiliary supply, without de-energising. Watchdog Contacts...
  • Page 22 P74x/EN TD/Na7 Technical Data (TD) 2-6 MiCOM P741, P742, P743 Type Tests Electrical Fast Transient or Burst Requirements Per IEC 60255-22-4: 2002. Test severity Class Insulation III and IV: Per IEC 60255-5: 2000, Amplitude: 2 kV, burst frequency 5 kHz Insulation resistance >...
  • Page 23 Technical Data P74x/EN TD/Na7 MiCOM P741, P742, P743 (TD) 2-7 Surge Immunity Test EU Directives (EIA RS232 ports excepted). Per IEC 61000-4-5: 2002 Level 4, EMC Compliance Time to half-value: 1.2 / 50 µs, Per 89/336/EEC: Amplitude: 4 kV between all groups and...
  • Page 24 P74x/EN TD/Na7 Technical Data (TD) 2-8 MiCOM P741, P742, P743 Transient overreach and overshoot Performance Data Busbar Protection Accuracy Additional tolerance due to increasing X/R ratios: ± 5% over the X/R ratio of 1 to 90 Busbar fault Accuracy Pick-up: Setting ± 5% or 20 A up to 8 Pus, or Overshoot of overcurrent elements: <...
  • Page 25 Technical Data P74x/EN TD/Na7 MiCOM P741, P742, P743 (TD) 2-9 IEC 61850 Ethernet data Protection functions 10 Base T/100 Base TX Communications Global Settings (System Data) Interface in accordance with IEEE802.3 and Language: English/French/German/Spanish IEC61850 Frequency: 50/60 Hz Isolation 1.5kV...
  • Page 26 P74x/EN TD/Na7 Technical Data (TD) 2-10 MiCOM P741, P742, P743 Current transformer and feeder Breaker failure protection (PU) characteristics Caution: the following current set values are expressed in multiple of the local CT’s nominal Class: 5P (IEC185) rated current Inp (primary) or Ins (secondary).
  • Page 27 Technical Data P74x/EN TD/Na7 MiCOM P741, P742, P743 (TD) 2-11 I>2 Function: CB Control (PU) Disabled, 87BBP&N blocking, High Set I>2, Prot Trip Pulse: 0.05…2.00s (step 10mss) I>2 & 87BBP&N, 87BB/P blocking, 87BB/N Trip Latched: Disabled/Enabled blocking, I>2 & 87BB/P or I>2 & 87BB/N...
  • Page 28 P74x/EN TD/Na7 Technical Data (TD) 2-12 MiCOM P741, P742, P743 Measurements and records List Communications RP1 Protocol: Courier Fault Recorder RP1 Address (courier): 6…34 Records for the last 5 faults Inactivity Timer: 1…30 minutes RP1 Port Config (Courier): Central Unit: K Bus / EIA485 (RS485) •...
  • Page 29 User defined text string to describe the function of the particular opto input. Outputs Labels Relay 1 up to: 8 for P741 & P742 16 for P743 User defined text string to describe the function of the particular relay output contact.
  • Page 30 P74x/EN TD/Na7 Technical Data (TD) 2-14 MiCOM P741, P742, P743...
  • Page 31 Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 GETTING STARTED Hardware Suffix: J and K Software Version:...
  • Page 32 P74x/EN GS/Na7 Getting Started MiCOM P741, P742, P743...

  • Page 33: Table Of Contents

    Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-1 CONTENTS GETTING STARTED User interfaces and menu structure Introduction to the relay 1.2.1 Front panel 1.2.2 Relay rear panel Relay connection and power-up Introduction to the user interfaces and settings options Menu structure 1.5.1...

  • Page 34: Table Of Contents

    FIGURE 2: RELAY FRONT VIEW (EXAMPLE FOR P743 – 60 TE) FIGURE 3: P742 RELAY REAR VIEW 40TE FIGURE 4: P743 RELAY REAR VIEW 60TE FIGURE 5: P741 RELAY REAR VIEW 80TE FIGURE 6: MENU STRUCTURE FIGURE 7: FRONT PANEL USER INTERFACE...

  • Page 35: Getting Started

    1.2.1 Front panel The front panel of the relay is shown in Figure 1 (P742) or 2 (P741 or P743), with the hinged covers at the top and bottom of the relay shown open. Extra physical protection for the front panel can be provided by an optional transparent front cover.

  • Page 36: Figure 2: Relay Front View (Example For P743 – 60 Te)

    P74x/EN GS/Na7 Getting Started (GS) 3-4 MiCOM P741, P742, P743 • a 16-character by 3-line alphanumeric liquid crystal display (LCD). (     and  ), • a 9-key keypad comprising 4 arrow keys an enter key ( ), a ...
  • Page 37 Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-5 When the functionality is disabled: − For control of setting groups, control inputs and circuit breaker operation − 22 LEDs; 4 fixed function LEDs, 8 tri-colour programmable function LEDs on the left...
  • Page 38 P74x/EN GS/Na7 Getting Started (GS) 3-6 MiCOM P741, P742, P743 The default mappings for each of the programmable LEDs are as shown in the following table: Central Unit P741: LED Input Connection/Text Latched P74x LED Function Indication Number LED1 Red...
  • Page 39 Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-7 LED Input Connection/Text Latched P74x LED Function Indication Number FnKey LED5 Red Zone 2: 87BB & 50BF blocked FnKey LED5 Yellow Zone 2: 50BF blocked FnKey LED5 Green Zone 2: protected...
  • Page 40 P74x/EN GS/Na7 Getting Started (GS) 3-8 MiCOM P741, P742, P743 Peripheral Unit P743: LED Input Connection/Text Latched P74x LED Function Indication Number LED1 Red Isolator 1 Closed LED1 Yellow Isolator 1 Status Alarm LED1 Green Isolator 1 Open LED2 Red...

  • Page 41: Relay Rear Panel

    EIA(RS)485 communication port; the IRIG-B time synchronising input is optional in the P741, the Ethernet rear communication board with copper and fiber optic connections or the second communication and InterMiCOM board are optional in the P741 and P743.

  • Page 42: Figure 4: P743 Relay Rear View 60Te

    P74x/EN GS/Na7 Getting Started (GS) 3-10 MiCOM P741, P742, P743 FIGURE 4: P743 RELAY REAR VIEW 60TE FIGURE 5: P741 RELAY REAR VIEW 80TE Refer to the wiring diagram in the ‘Installation Chapter’ (P74x/EN IN) for the complete connection details.

  • Page 43: Relay Connection And Power-Up

    Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-11 Relay connection and power-up Before powering-up the relay, confirm that the relay power supply voltage and nominal ac signal magnitudes are appropriate for your application. The relay serial number, and the relay’s current and voltage rating, power rating information can be viewed under the top...

  • Page 44: Menu Structure

    P74x/EN GS/Na7 Getting Started (GS) 3-12 MiCOM P741, P742, P743 Keypad/ IEC870-5- Courier 61850 Display & modification of • • all settings • • • • Digital I/O signal status Display/extraction of • • • • measurements Display/extraction of fault •...

  • Page 45: Control And Support Settings

    Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-13 All of the settings in the menu fall into one of three categories; protection settings, disturbance recorder settings, or control and support (C&S) settings. One of two different methods is used to change a setting depending on which category the setting falls into.

  • Page 46: Relay Configuration

    If the passwords are lost an emergency password can be supplied - contact GE with the relay’s serial number. The current level of access enabled for an interface can be determined by examining the 'Access level' cell in the 'System data' column, the access level for the front panel User Interface (UI), can also be found as one of the default display options.

  • Page 47: Default Display And Menu Time-Out

    Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-15 FIGURE 7: FRONT PANEL USER INTERFACE 1.8.1 Default display and menu time-out The front panel menu has a default display, the contents of which can be selected from the following options in the ‘default display’ cell of the ‘Measure’t. setup’ column: −...

  • Page 48: Menu Navigation And Setting Browsing

    P74x/EN GS/Na7 Getting Started (GS) 3-16 MiCOM P741, P742, P743 1.8.2 Menu navigation and setting browsing The menu can be browsed using the four arrow keys, following the structure shown in Figure  7. Thus, starting at the default display the key will display the first column heading.

  • Page 49: Password Entry

    Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-17 1.8.3.3 Hotkey menu navigation Default Displ a y Description MiCOM P741 HO TKEY <STG GP <USER 31 USER 02> MENU> <USER 32 <MENU USER 01> STG GP> HO T KEY MENU...

  • Page 50: Setting Changes

    Courier communication protocol only. Courier is the communication language developed by GE to allow communication with its range of protection relays. The front port is particularly designed for use with the relay settings program S1 that is a Windows 98,...

  • Page 51: Figure 9: Front Port Connection

    Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-19 FIGURE 9: FRONT PORT CONNECTION The relay is a Data Communication Equipment (DCE) device. Thus the pin connections of the relay’s 9-pin front port are as follows: Pin no. 2 Tx Transmit data Pin no.

  • Page 52: Front Courier Port

    P74x/EN GS/Na7 Getting Started (GS) 3-20 MiCOM P741, P742, P743 FIGURE 10: PC – RELAY SIGNAL CONNECTION Having made the physical connection from the relay to the PC, the PC’s communication settings must be configured to match those of the relay. The relay’s communication settings...

  • Page 53: Off-Line Use Of S1 Agile

    Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-21 This section is intended as a quick start guide to using S1 Agile and assumes you have a copy installed on your PC. See the S1 Agile program online help or ‘MiCOM P40 Agile Modular and Compact Ranges, Settings Application Software User Guide’, P40-M&CR-UG...

  • Page 54: Configuring The Ethernet Interface

    P74x/EN GS/Na7 Getting Started (GS) 3-22 MiCOM P741, P742, P743 CONFIGURING THE ETHERNET INTERFACE The way in which you configure the Ethernet interface depends on the particular type of interface you have. If you have a DNP3.0 interface, use the DNP setting file to configure the Ethernet interface.
  • Page 55 Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-23 8. Select the model. The IP address data is then revealed: 9. To change the address values, select View > Enter Manual Editing Mode 10. Enter the required IP configuration and select the green download button:...

  • Page 56: Configuring The Redundant Ethernet Board

    P74x/EN GS/Na7 Getting Started (GS) 3-24 MiCOM P741, P742, P743 CONFIGURING THE REDUNDANT ETHERNET BOARD An IP address is a logical address assigned to devices in a computer network that uses the Internet Protocol (IP) for communication between nodes. IP addresses are stored as binary...

  • Page 57: Rstp Configuration

    Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-25 Configuring the Third Octet of the Board IP Address The third octet is fixed at 254 (FE hex, 11111110 binary regardless of the protocol. Configuring the Last Octet of the Board IP Address The last octet is configured using the 8-way board address DIP switch SW2 on the REB.
  • Page 58 P74x/EN GS/Na7 Getting Started (GS) 3-26 MiCOM P741, P742, P743 2. The Login screen appears. For user mode login, enter the Login name as User and click OK with no password. 3. If the login screen does not appear, check all network connections.
  • Page 59 Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-27 2. Enter the required SNTP MAC and server IP address, then click OK. The updated SNTP server IP address appears in the main screen. Equipment 1. To view the MAC addresses learned by the switch, go to the main window and click the Identify Device button.
  • Page 60 P74x/EN GS/Na7 Getting Started (GS) 3-28 MiCOM P741, P742, P743 1. To view the available parameters in the board that is connected, click the Get RSTP Parameters button. 2. To set the configurable parameters such as Bridge Max Age, Bridge Hello Time,...
  • Page 61 Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-29 Port States This is used to see which ports of the board are enabled or disabled. 1. From the main window, click the device address to select the device. The RSTP Config window appears.

  • Page 62: Configuring The Data Protocols

    P74x/EN GS/Na7 Getting Started (GS) 3-30 MiCOM P741, P742, P743 CONFIGURING THE DATA PROTOCOLS Depending on the model, various protocols can be used with the serial rear ports. However, only one protocol can be configured at any one time on any one IED. The range of available...

  • Page 63: Iec 61850 Configuration

    IED. Note: To help the user, some configuration data is available in the IED CONFIGURATOR column, allowing read-only access to basic configuration data. Note: The IEC 61850 option is only available on the P741 and the P743.

  • Page 64: Iec 61850 Configuration Banks

    P74x/EN GS/Na7 Getting Started (GS) 3-32 MiCOM P741, P742, P743 4.3.1 IEC 61850 Configuration Banks To help version management and minimize down-time during system upgrades and maintenance, the MiCOM IEDs have incorporated a mechanism consisting of multiple configuration banks. These configuration banks fall into two categories: −...

  • Page 65: Prp/Hsr Configurator

    Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-33 PRP/HSR CONFIGURATOR The PRP/HSR Configurator tool is intended for MiCOM Px4x IEDs with redundant Ethernet using PRP (Parallel Redundancy Protocol), or HSR (High-availability Seamless Redundancy). This tool is used to identify IEDs, switch between PRP and HSR or configure their parameters, configure the redundancy IP address, or configure the SNTP IP address.

  • Page 66: Prp/Hsr Device Identification

    P74x/EN GS/Na7 Getting Started (GS) 3-34 MiCOM P741, P742, P743 5. The Network Board drop-down list shows the Network Board, IP Address and MAC Address of the 6. PC in which the Configurator is running. PRP/HSR device identification To configure the redundant Ethernet board, go to the main window and click the Identify Device button.

  • Page 67: Hsr Configuration

    Getting Started P74x/EN GS/Na7 MiCOM P741, P742, P743 (GS) 3-35 If you need to restore the default values of the parameters, click the Restore Defaults button. The configurable parameters are as follows: • Multicast Address: Use this field to configure the multicast destination address. All DANPs in the network must be configured to operate with the same multicast address for the purpose of network supervision.

  • Page 68: End Of Session

    P74x/EN GS/Na7 Getting Started (GS) 3-36 MiCOM P741, P742, P743 2. To view the Forwarding Database Size, Number of Static Entries and Number of Dynamic Entries, click Read Database Info. 3. To set the Aging Time, enter the number of seconds in the text box and click the Set button.
  • Page 69 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 SETTINGS Hardware Suffix: J and K Software Version:...
  • Page 70 P74x/EN ST/Na7 Getting Started MiCOM P741, P742, P743...
  • Page 71 Default settings restore 1.1.6 “Date and time” column Protection settings 1.2.1 Differential Protection Configuration (“Diff Busbar Prot” menu – P741) 1.2.2 Differential Protection Configuration (“Busbar option” column – P741) 1.2.3 Busbar Trip (87BB) or Central Breaker Fail BackTrip Confirmation (50BF) (“BB Trip Confirm”...
  • Page 72 P74x/EN ST/Na7 Settings (ST) 4-2 MiCOM P741, P742, P743...
  • Page 73 1.1.1 “System data” column 1.1.1.1 Central Unit P741 This menu provides information for the device and general status of the P741 relay. Setting Range Menu Text Default Setting Step Size Min.
  • Page 74 Relay Address Fixed front and first rear port relay address. Plant Status 0000000000000000 Displays the circuit breaker plant status for up to 8 circuit breakers. The P741 relay does not support any circuit breaker. Not used Control Status 0000000000000000 Not used.
  • Page 75 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-5 Setting Range Menu Text Default Setting Step Size Min. Max. SYSTEM DATA Password Level 2 **** Allows user to change password level 2. 1.1.1.2 Peripheral Units P742 and P743 Setting Range...
  • Page 76 Password Level 1 **** Allows user to change password level 1. Password Level 2 **** Allows user to change password level 2. 1.1.2 “Configuration” column (P741 Central Unit) Menu Text Default Setting Available Settings CONFIGURATION No Operation All Settings Setting Group 1...
  • Page 77 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-7 Menu Text Default Setting Available Settings Select via Menu Setting Group Select via Menu Select via Optos Allows setting group changes to be initiated via Opto Input or via Menu. Group 1, Group 2, Group 3,...
  • Page 78 P74x/EN ST/Na7 Settings (ST) 4-8 MiCOM P741, P742, P743 Menu Text Default Setting Available Settings Control Inputs Visible Invisible or Visible Activates the Control Input status and operation menu further on in the relay setting menu. Ctrl I/P Config. Visible Invisible or Visible Sets the Control Input Configuration menu visible further on in the relay setting menu.
  • Page 79 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-9 MENU TEXT Default Setting Available Settings CONFIGURATION Copy to No Operation No Operation / Group 1 / Group 2 Group 3 / Group 4 Allows displayed settings to be copied to a selected setting group (ready to paste).
  • Page 80 (integrated teleprotection) (when option available). Function Key Visible Invisible or Visible P741 / P743 only: Sets the Function Key menu visible further on in the relay setting menu. RP1 Read Only Disabled Enabled or Disabled If this Read Only mode is enabled, then all setting changes and most command/control actions are blocked (not accepted by the relay) for Rear Port 1.
  • Page 81 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-11 MENU TEXT Default Setting Available Settings PU CONF & STATUS PU in service 0000000000000000 0 or 1 00000000000 List of the PUs in service. For example a topology scheme may define 12 PU: 5 PU for current phase and 7 PU for future.
  • Page 82 Enable IRIG-B time synchronization (P741 only and with Irig-B option). Card not fitted/Card failed/ Signal healthy/No IRIG-B Status Data signal Displays the status of IRIG-B (P741 only and with Irig-B option). Battery Status Data Displays whether the battery is healthy or not. Battery Alarm...
  • Page 83 Tunnel Time Zone Local UTC or Local For P741 and P743 with Ethernet option only: Setting to specify if time synchronisation received will be local or universal time co-ordinate when ‘tunnelling’ courier protocol over Ethernet. Protection settings The protection settings include all the following items that become active once enabled in the configuration column of the relay menu database: −...
  • Page 84 The settings for group 1 are shown. The settings are discussed in the same order in which they are displayed in the menu. 1.2.1 Differential Protection Configuration (“Diff Busbar Prot” menu – P741) Differential Elements 87BB The differential element has independent settings for phase and earth (sensitive) faults, which are used for all zones and the check zone independently.
  • Page 85 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-15 1.2.1.2 Sensitive earth fault element The sensitive earth fault element is included for high impedance earthed systems and has bias current control to guarantee stability under external faults or when there are significant errors in the measurement CTs.
  • Page 86 (ST) 4-16 MiCOM P741, P742, P743 1.2.2 Differential Protection Configuration (“Busbar option” column – P741) The differential element blockings and alarms can be configured to fit optimum operability, they are used for all zones and the check zone independently. This column is visible when the “Busbar Option” setting (“Configuration” column) = “visible”.
  • Page 87 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-17 Setting Range Menu Text Default Setting Step Size Min. Max. BUSBAR OPTION Circuitry tReset 5.0s 0.0s 600.0s 0.1s Setting for the reset time delay of the circuitry fault reset options Circ. Block Mode...
  • Page 88 P741. Disabled: If the Sensitive Differential Earth Fault Protection (87BB/N) is blocked, the associated alarm is not raised and is not present on the front panel of the P741. Confirm Reset PU Enabled Enabled / Disabled Enables or disables the PU error auto- reset.
  • Page 89 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-19 1.2.4 Dead Zone configuration (“Dead Zone Prot” menu – P742/P743) Setting Range Menu Text Default Setting Step Size Min. Max. Dead Zone Prot I>DZ Current Set 1.20*I 0.05*I 4.00*I 0.01*I Setting for the tripping characteristic for the minimum pickup phase dead zone element I>DZ Time Delay...
  • Page 90 P74x/EN ST/Na7 Settings (ST) 4-20 MiCOM P741, P742, P743 Setting Range Menu Text Default Setting Step Size Min. Max. I>1 Time Dial 15.0 Setting for the time multiplier setting to adjust the operating time of the IEEE/US IDMT curves. I>1 Reset Char DT/Inverse Setting to determine the type of reset/release characteristic of the IEEE/US curves.
  • Page 91 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-21 Setting Range Menu Text Default Setting Step Size Min. Max. Ι >1 Current Set 0.30*Ι 0.10*Ι 32.00*Ι 0.01*Ι Pick-up setting for the first stage earth fault element. Ι 1.00s 0.00s 100.00s 0.01s...
  • Page 92 P74x/EN ST/Na7 Settings (ST) 4-22 MiCOM P741, P742, P743 Setting Range Menu Text Default Setting Step Size Min. Max. CB FAIL Control by I< I< / 52a / both Setting which determines the elements that will reset the circuit breaker fail time protection function.
  • Page 93 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-23 Setting Range Menu Text Default Setting Step Size Min. Max. CT Supervision Sub-heading CTS Timer alarm 5.0 s 0.1 s 10.0 s 0.1 s Setting that determines the alarm time-delay of the element upon detection of a current transformer supervision condition (current >10% IN present in the CT and difference...
  • Page 94 P74x/EN ST/Na7 Settings (ST) 4-24 MiCOM P741, P742, P743 Setting Range Menu Text Default Setting Step Size Min. Max. Man Close Pulse 0.50s 0.10s 10.00s 0.01s Defines the duration of the close pulse. Man Trip Pulse 0.50s 0.10s 5.00s 0.01s Defines the duration of the trip pulse.
  • Page 95 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-25 Setting Range Menu Text Default Setting Step Size Min. Max. CT AND VT RATIOS Rated short-circuit factor K Sets the Current Transformer accuracy limit factor when the IEC standard has been chosen.
  • Page 96 P74x/EN ST/Na7 Settings (ST) 4-26 MiCOM P741, P742, P743 Setting Range Menu Text Default Setting Step Size Min. Max. RECORD CONTROL Menu Text Default Setting Available Settings Disabling this setting means that no event will be generated for any fault that produces a fault record Maint.
  • Page 97 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-27 1.3.5 “Communications” column The communications settings apply to the rear communications port. Further details are given in the SCADA communications section (P74x/EN SC). These settings are available in the menu ‘Communications’ column and are displayed when the “Comms Settings”...
  • Page 98 P74x/EN ST/Na7 Settings (ST) 4-28 MiCOM P741, P742, P743 Setting Range Menu Text Default Setting Step Size Min. Max. COMMUNICATIONS Ethernet MAC Address NIC MAC Address Indicates the MAC (Media Access Control) address of the rear Ethernet port. This address is formatted as a six-byte hexadecimal number, and is unique.
  • Page 99 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-29 Setting Range Menu Text Default Setting Step Size Min. Max. COMMUNICATIONS RP2 Baud Rate 19200 bits/s 9600 bits/s, 19200 bits/s or 38400 bits/s This cell controls the communication speed between relay and master station.
  • Page 100 P74x/EN ST/Na7 Settings (ST) 4-30 MiCOM P741, P742, P743 Menu Text Default Setting Available Settings COMMISSION TESTS Test Mode Disabled Disabled /Out Of Service The Test Mode menu cell is used to allow secondary injection testing to be performed on a Peripheral Unit relay without operation of the connected zone.
  • Page 101 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-31 Menu Text Default Setting Available Settings COMMISSION TESTS BB Trip Order No Operation No Operation / Apply Test / Remove Test Visible when “Test Mode“ is disabled When the ‘Apply Test’ command in this cell is issued the Central Unit sends the trip orders for the zone(s) set for operation (set to ‘1’) in the ‘BB Trip Pattern’...
  • Page 102 P74x/EN ST/Na7 Settings (ST) 4-32 MiCOM P741, P742, P743 Menu Text Default Setting Available Settings COMMISSION TESTS Monitor Bit 8 Relay Label 08 0 to 2047 The eight ‘Monitor Bit’ cells allow the user to select the status of which digital data bus signals can be observed in the ‘Test Port Status’...
  • Page 103 48/54V 220/250V Each opto input can individually be set to a nominal voltage value if custom is selected for the global setting. Opto Input 2 – 8 (P741) 24/27V, 30/34V, 48/54V, 110/125V, Opto Input 2 – 16 (P742) 48/54V 220/250V Opto Input 2 –...
  • Page 104 Allows the SET / RESET text to be changed to “ON / OFF”, “IN / OUT” etc. 1.3.10 “InterMiCOM Comm and Conf” columns (P741 / P743) The settings necessary for the implementation of InterMiCOM are contained within two columns of the relay menu structure: “InterMiCOM comms” and “InterMiCOM conf”. The two columns are visible when the “InterMiCOM”...
  • Page 105 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-35 Setting Range Menu Text Default Setting Step Size Min. Max. INTERMICOM COMMS Source Address Receive Address The “source” and “receive” addresses are used to synchronize remote and local relays. Both relays must be programmed with a unique pair of addresses that correspond with each other in the “Source Address”...
  • Page 106 P74x/EN ST/Na7 Settings (ST) 4-36 MiCOM P741, P742, P743 Setting Range Menu Text Default Setting Step Size Min. Max. INTERMICOM COMMS Message Status OK / Fail / Absent / Unavailable Indicates when the percentage of received valid messages has fallen below the “IM Msg Alarm Lvl”...
  • Page 107 When Cmd Type is enabled, Fallback Mode is enabled. Default values and frameSync type are settable when fallback mode selection is “latched”. 1.3.11 “Function keys” menu (P741 / P743) Available in the Central Unit P741 and the Peripheral Unit P743 Setting Range Menu Text Default Setting Step Size Min.
  • Page 108 Allows the text of the function key to be changed. 1.3.12 “IED Configurator” column (P741 / P743 only) The contents of the IED CONFIGURATOR column (for IEC 61850 configuration) are mostly data cells, displayed for information but not editable. In order to edit the configuration, it is necessary to use the IED (Intelligent Electronic Device) configurator tool within S1.
  • Page 109 When set to ‘Yes’, the test flag in the subscribed GOOSE message is ignored, and the data treated as normal. 1.3.13 “Control I/P (input) labels” column (P741 / P743 only) This column is visible when the “Control I/P Labels” setting (“Configuration” column) = “visible”.
  • Page 110 P74x/EN ST/Na7 Settings (ST) 4-40 MiCOM P741, P742, P743 Disturbance recorder settings The disturbance recorder settings include the record duration and trigger position, selection of analog and digital signals to record, and the signal sources that trigger the recording. The "DISTURBANCE RECORDER" menu columns are different for the Central Unit and the Peripheral Units as shown in the configuration columns below.
  • Page 111 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-41 The following lines give the default settings for digital inputs 2 to 32 Menu Text Default Setting Explanation Digital Input 2 Circt Flt Lck z2 Circuitry fault blocks zone 2 digital channel...
  • Page 112 P74x/EN ST/Na7 Settings (ST) 4-42 MiCOM P741, P742, P743 1.4.2 Peripheral Unit P742 or P743 Setting Range Menu Text Default Setting Step Size Min. Max. DISTURB. RECORDER Duration 1.2 s 1.2 s 10.5 s 0.01 s This sets the overall recording time. The relay can typically store up to 10.5 seconds until the available memory is exhausted.
  • Page 113 Settings P74x/EN ST/Na7 MiCOM P741, P742, P743 (ST) 4-43 Menu Text Default Setting Explanation Digital input 3 CB Closed CB Closed digital channel Input 3 trigger No Trigger Digital input 4 CB Fail Alarm CB Fail Alarm digital channel Input 4 trigger...
  • Page 114 P74x/EN ST/Na7 Settings (ST) 4-44 MiCOM P741, P742, P743 Menu Text Default Setting Explanation Input 22 trigger Trigger L/H Digital input 23 Trip 87BB Trip 87BB digital channel Input 23 trigger Trigger L/H Digital input 24 to 32 Unused The digital channels may be mapped to any of the opto isolated inputs or output contacts,...
  • Page 115 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 OPERATION Hardware Suffix: J and K Software Version:...
  • Page 116 P74x/EN OP/Na7 Operation MiCOM P741, P742, P743...
  • Page 117 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-1 CONTENTS OPERATION OF INDIVIDUAL PROTECTION FUNCTIONS Busbar Biased Current Differential Protection 1.1.1 Operating principle 1.1.2 Application of Kirchoffs law Busbar Protection 1.2.1 Bias Characteristic and Differential current setting 1.2.2 Scheme supervision by "check zone” element 1.2.3...
  • Page 118 P74x/EN OP/Na7 Operation (OP) 5-2 MiCOM P741, P742, P743 Optical budgets 5.3.1 Main operating features Trip LED logic Function keys 5.5.1 CB control using hotkeys 5.5.2 CB control using function keys Setting groups selection Control inputs FIGURES FIGURE 1: DIFFERENTIAL BUSBAR PROTECTION PRINCIPLE...
  • Page 119 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-3 FIGURE 28: REMOTE CONTROL OF CIRCUIT BREAKER FIGURE 29: MODULE INTERCONNECTION FIGURE 30: TRIP LED LOGIC DIAGRAM FIGURE 31: CB CONTROL HOTKEY MENU FIGURE 32: CB CONTROL VIA FUNCTION KEYS DEFAULT PSL...
  • Page 120 P74x/EN OP/Na7 Operation (OP) 5-4 MiCOM P741, P742, P743...
  • Page 121 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-5 OPERATION OF INDIVIDUAL PROTECTION FUNCTIONS The following sections detail the individual protection functions. Note however that not all the protection functions listed below are applicable to every relay. Busbar Biased Current Differential Protection The primary protection element of the P74x scheme is phase segregated biased current differential protection.
  • Page 122 P74x/EN OP/Na7 Operation (OP) 5-6 MiCOM P741, P742, P743 The other advantage of using an instantaneous sum lies in the speed of decision, which in turn is dictated by the sampling frequency. Differential currents may also be generated under external fault conditions due to CT error.
  • Page 123 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-7 Busbar Protection 1.2.1 Bias Characteristic and Differential current setting Figure 2 shows the characteristics of the P74x scheme phase differential element. FIGURE 2: P74x SCHEME CHARACTERISTIC The Phase characteristic is determined from the following protection settings: •...
  • Page 124 P74x/EN OP/Na7 Operation (OP) 5-8 MiCOM P741, P742, P743 The check zone is the sum of all the current nodes entering and leaving the substation (feeders). Scheme differential current = sum of all differential current feeder nodes: (t) CZ = Σ i ...
  • Page 125 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-9 FIGURE 4: SENSITIVE EARTH FAULT BLOCKING CHARACTERISTIC For an external phase fault the SDEF protection will be disabled by the blocking command as long as the 'IbiasPh>Cur.' threshold remains exceeded. It can be seen that for an internal phase to phase fault the bias current will be sufficient to enable the SDEF blocking order.
  • Page 126 P74x/EN OP/Na7 Operation (OP) 5-10 MiCOM P741, P742, P743 Table below shows operation depending on the thresholds' status. >1 k1.I >2 Status Operation bias Normal No operation Normal No operation Normal No operation External fault or External fault with CT saturation or...
  • Page 127 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-11 • Bias characteristic ( I > (I CZ>2)) and Differential current setting are not diff exceeded (I > kCZ I ) for the check zone for at least 1 sample in the 4...
  • Page 128 P74x/EN OP/Na7 Operation (OP) 5-12 MiCOM P741, P742, P743 There were 3 options: Blocking Latched An alarm is provided and this alarm can only be reset manually, The zone is blocked and this blocking can only be reset manually. Alarm Latched...
  • Page 129 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-13 1.2.8.2 Protection options for the Check Zone 1.2.8.2.1 Options for a Circuitry Fault There are 5 options: Blocking Latched An alarm is provided and this alarm can only be reset manually, The Check Zone is blocked and this blocking can only be reset manually.
  • Page 130 Central Unit via an output contact to opto input communication link. The required logic is made in the P741 PSL. The 87BB trip order can be blocked in the CU using 2 logic input sets, one to block the phase element, the second to block the SEF element and that per zone: •...
  • Page 131 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-15 The 87BB trip order can be blocked in the PU using 2 logic inputs, one to block the phase element, the second to block the SEF element: • INP Block 87BB/P •...
  • Page 132 P74x/EN OP/Na7 Operation (OP) 5-16 MiCOM P741, P742, P743 1.3.3 Circuit Breaker Fail (CBF) The detailed logic of the circuit breaker failure element follows. 1.3.3.1 Distributed Tripping, Control and Indication Elements (Peripheral Units) As the P74x scheme has been designed for use as either a centralised or distributed...
  • Page 133 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-17 The output signal is pl(t), it changes between 0 and 1. Internal overcurrent signals are available per phase and neutral to confirm that the CB failure algorithm has started to count down.
  • Page 134 P74x/EN OP/Na7 Operation (OP) 5-18 MiCOM P741, P742, P743 FIGURE 7: CB ELEMENT LOGIC Principle of the undercurrent function. Instantaneous current measurements are taken for both the positive and negative half cycles, ensuring immunity to DC offset waveforms, and CT current ring-down.
  • Page 135 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-19 1.3.3.2.3 Logic reset Criterion This is for instances where circuits may carry a very low level of load, or even may operate unloaded from time to time. Where 52a contact (CB closed) supervision is set, the relay looks only for 52a resetting to stop the breaker fail timers.
  • Page 136 P74x/EN OP/Na7 Operation (OP) 5-20 MiCOM P741, P742, P743 FIGURE 8: CB FAIL LOGIC...
  • Page 137 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-21 DDB Ext. CB Fail >1 DDB BF Trip Request Trip signal towards CU DDB O/C Protection DDB Ext. 3ph Trip DDB External Trip A >1 DDB CBF Ext Backtrip DDB External Trip B >1...
  • Page 138 P74x/EN OP/Na7 Operation (OP) 5-22 MiCOM P741, P742, P743 1.3.3.2.6.1 Description of the Logic for Internally Initiated CBF Trip signal from CU : T ripping signal from 87BB Local & pABC Main busbar protection trip signal Circuit Breaker I>BB (note 2)
  • Page 139 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-23 CU 87BB Back Trip Order (4) CB Fail signal (3) Trip Order (1) Other Main Trip Protection or Retrip Failed Back Trip 50BF 50BF 50BF P3758ENa FIGURE 11: CIRCUIT BREAKER FAILURE LOGIC...
  • Page 140 P74x/EN OP/Na7 Operation (OP) 5-24 MiCOM P741, P742, P743 1.3.3.2.7 Externally Initiated 50BF FIGURE 13: CB FAIL ELEMENT LOGIC – EXTERNALLY INITIATED Taking into account the relationship between the busbar protection and the circuit breaker failure protection certain operators prefer an integrated solution where the breaker failure may be initiated by external protection but executed in the busbar scheme.
  • Page 141 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-25 1.3.3.2.9 CB Fail alarm The CB Fail alarm is raised on any timer reached (tBF2 or tBF4) 1.3.3.2.10 Separate external 50BF protection to the busbar protection This is the most common solution utilising conventional wiring. The 50BF relay is completely independent of all others.
  • Page 142 P74x/EN OP/Na7 Operation (OP) 5-26 MiCOM P741, P742, P743 The definite time can be set (as defined in IEC) to zero. Range 0 to 100 seconds in steps of 0.01 seconds. The Inverse Reset characteristics are dependent upon the selected IEEE/US IDMT curve as shown in the table below.
  • Page 143 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-27 During an earth fault the two values should be the same and the sum should therefore be equal to zero or below the threshold (CTS Ι > Set) and the CT supervision alarm will not be issued.
  • Page 144 P74x/EN OP/Na7 Operation (OP) 5-28 MiCOM P741, P742, P743 Only the second type of teleprotection is available within the P741 and P743, providing that the corresponding hardware is fitted. 1.5.6.1 Protection signaling In order to achieve fast fault clearance and correct discrimination for faults anywhere within a high voltage power network, it is necessary to signal between the points at which protection relays are connected.
  • Page 145 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-29 The requirements for the three channel types are represented pictorially in the following figure: FIGURE 15: PICTORIAL COMPARISON OF OPERATING MODES This diagram shows that a blocking signal should be fast and dependable; a direct intertrip signal should be very secure and a permissive signal is an intermediate compromise of speed, security and dependability.
  • Page 146 P74x/EN OP/Na7 Operation (OP) 5-30 MiCOM P741, P742, P743 1.5.7.2 General features & implementation InterMiCOM provides 8 commands over a single communications link, with the mode of operation of each command being individually selectable within the “IM# Cmd Type” cell.
  • Page 147 15m. However, this may be extended by introducing suitable EIA(RS)232 to fiber optic converters, such as the GE CILI203. Depending upon the type of converter and fiber used, direct communication over a few kilometers can easily be achieved.
  • Page 148 P74x/EN OP/Na7 Operation (OP) 5-32 MiCOM P741, P742, P743 1.5.7.5 Modem connection For long distance communication, modems may be used in which the case the following connections should be made. FIGURE 17: InterMiCOM TELEPROTECTION VIA A MODEM LINK This type of connection should also be used when connecting to multiplexers which have the ability to control the DCD line.
  • Page 149 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-33 It should be noted that when an InterMiCOM signal is sent from the local relay, only the remote end relay will react to this command. The local end relay will only react to InterMiCOM commands initiated at the remote end.
  • Page 150 P74x/EN OP/Na7 Operation (OP) 5-34 MiCOM P741, P742, P743 CURRENT TRANSFORMERS CT Saturation detection Innovative methods are used to detect CT saturation in the P74x. The values associated with the CT saturation algorithms are entered into the Peripheral Unit’s CT ratio menu column and are used to define the CT’s characteristic.
  • Page 151 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-35 The second algorithm, by integration of the secondary current, presumes of maximum flux in the HV CT core. The flux calculation starts when the first variation of current is detected, then if the calculated flux reached 20% of the maximum flux, a CT saturation is presumed as shown in figure 21.
  • Page 152 P74x/EN OP/Na7 Operation (OP) 5-36 MiCOM P741, P742, P743 CT saturation is detected after a variation of current, detection of a presumption of maximum flux and current reversal, as shown figure 23. When CT saturation appears, a blocking order is sent to the CU to block all zones (the check zone is blocked).
  • Page 153 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-37 P3774ENa FIGURE 25: DETERMINATION OF SIGNAL QUALITY IN THE PERIPHERAL UNIT CT Location There are no restriction imposed as to the location of current transformers within the system, however, when the topological model is created, the position and orientation of the current transformers must be defined correctly to ensure the correct operation of the protection.
  • Page 154 P74x/EN OP/Na7 Operation (OP) 5-38 MiCOM P741, P742, P743 ISOLATOR AND CIRCUIT BREAKER FUNCTION Isolator State Monitoring Features MiCOM relays can be set to monitor normally open (89A) and normally closed (89B) auxiliary contacts of the isolators. Under healthy conditions, these contacts will be in opposite states.
  • Page 155 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-39 No CB status available directly affects any function within the relay that requires this signal, for example CB control, Topology for buscoupler, etc. If both 52A and 52B are used then status information will be available and in addition a discrepancy alarm will be possible, according to the following table.
  • Page 156 P74x/EN OP/Na7 Operation (OP) 5-40 MiCOM P741, P742, P743 FIGURE 27: CB STATE MONITORING FEATURES Circuit Breaker Control The relay includes the following options for control of a single circuit breaker: Local tripping and closing, via the relay menu Local tripping and closing, via relay opto-isolated inputs It is recommended that separate relay output contacts are allocated for remote circuit breaker control and protection tripping.
  • Page 157 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-41 be necessary to use the breaker 52A and/or 52B contacts via PSL. If no CB auxiliary contacts are available no CB control (manual or auto) will be possible. Once a CB Close command is initiated the output contact can be set to operate following a user defined time delay (‘Man Close Delay’).
  • Page 158 Pulse conditioner timer IRIG-B signal (P741) only If a satellite time clock signal conforming to IRIG-B is provided and the P741 relay has the optional IRIG-B port fitted, the satellite clock equipment should be energised. In the event of the auxiliary supply failing, with a battery fitted in the compartment behind the bottom access cover, the time and date will be maintained.
  • Page 159 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-43 COMMUNICATIONS BETWEEN PU AND CU The P74x scheme can be either centralised in one cubicle or distributed in cubicles housing other protection depending on the availability of space. Either way the Peripheral Units still need to communicate with the central unit and vice versa.
  • Page 160 P74x/EN OP/Na7 Operation (OP) 5-44 MiCOM P741, P742, P743 Optical budgets When using fibre optics as a method of communication the type of fibre used and the distance between devices needs to be considered. The following table shows the optical budgets of the communications interface.
  • Page 161 (OP) 5-45 Function keys The P741 and P743 relays offer users 10 function keys for programming any operator control functionality such as auto-reclose ON/OFF, earth fault1 ON/OFF etc. via PSL. Each function key has an associated programmable tri-colour LED that can be programmed to give the desired indication on function key activation.
  • Page 162 P74x/EN OP/Na7 Operation (OP) 5-46 MiCOM P741, P742, P743 To avoid accidental operation of the trip and close functionality, the hotkey CB control commands will be disabled for 10 seconds after exiting the hotkey menu. P2246ENm FIGURE 31: CB CONTROL HOTKEY MENU 5.5.2...
  • Page 163 Operation P74x/EN OP/Na7 MiCOM P741, P742, P743 (OP) 5-47 Setting groups selection The setting groups can be changed either via opto inputs, via a menu selection, via the hotkey menu or via function keys. In the Configuration column if 'Setting Group - select via optos' is selected then any opto input or function key can be programmed in PSL to select the setting group as shown in the table below.
  • Page 164 P74x/EN OP/Na7 Operation (OP) 5-48 MiCOM P741, P742, P743 The “CTRL. I/P CONFIG.” column has several functions one of which allows the user to configure the control inputs as either ‘latched’ or ‘pulsed’. A latched control input will remain in the set state until a reset command is given, either by the menu or the serial communications.
  • Page 165 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 APPLICATION NOTES Hardware Suffix: J and K Software Version:...
  • Page 166 P74x/EN AP/Na7 Application Notes MiCOM P741, P742, P743...
  • Page 167 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-1 CONTENTS INTRODUCTION Protection of Substation Busbars APPLICATION OF INDIVIDUAL PROTECTION FUNCTIONS Busbar Protection 2.1.1 Busbar Protection Setting guidelines Additional protections 2.2.1 Dead Zone protection (DZ) 2.2.2 Over Current protection (OC) 2.2.3...
  • Page 168 P74x/EN AP/Na7 Application Notes (AP) 6-2 MiCOM P741, P742, P743 Topology processing 6.5.1 Single bar or double bus with bus sectionaliser 6.5.2 Double bus with one CT bus coupler 6.5.3 Double bus with two CT bus coupler 6.5.4 CTs on one side of bus coupler, CB closes before status acquisition.
  • Page 169 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-3 INTRODUCTION Before carrying out any work on the equipment, the user should be familiar with the contents of the safety section/safety guide Pxxx-SG-4LM-2 or later issue, the technical data section and the ratings on the equipment rating label.
  • Page 170 There are three modules that make up the P74x scheme. The P741 is the Central Unit (CU), whilst the P742 and P743 are both variants of the Peripheral Unit (PU). The central unit co-ordinates the scheme, receiving signals from all the peripheral units associated with the protected busbar(s) and acting on these signals, initiating a bus zone protection trip when necessary.
  • Page 171 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-5 An Excel spreadsheet tool called “Idiff_Ibias“ is available on request to assure a reliable setting choice: 2.1.1.1.1 Sub-station features Only 6 values have to be known: Minimum load current in a feeder...
  • Page 172 P74x/EN AP/Na7 Application Notes (AP) 6-6 MiCOM P741, P742, P743 2.1.1.1.3 Differential Busbar Protection ID>1 (from 5 A to 500 A (primary value)) as high as possible Slope k1 (ID>1) (from 0% to 50%), recommendation is 10% ID>2 (from 50 A to 50000 A (primary value)) as low as possible, whilst ensuring the single CT failure will not cause tripping under maximum load conditions Slope k2 (ID>2) (from 20% to 90%), recommendation is generally 65%...
  • Page 173 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-7 • when all these buses are independent (bus sectionalizers open) • the maximum load is on all the buses (biggest bias current) • The internal short-circuit value is minimum. Max Load...
  • Page 174 P74x/EN AP/Na7 Application Notes (AP) 6-8 MiCOM P741, P742, P743 • the maximum load is on the 2 buses (biggest bias current) • The internal short-circuit value is minimum. During the internal fault: • the CZ bias current is: Icc min (1 bar) + 4 x IloadMax (1 bar) •...
  • Page 175 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-9 ID>1 Alarm Timer to not operate for an external fault shall be greater than the longest protection time (such as line, overcurrent, etc…) Slope k2 (ID>2) recommendation is 65% To be always stable in the worth CT ratio conditions (between the biggest CT and the smallest CT).
  • Page 176 P74x/EN AP/Na7 Application Notes (AP) 6-10 MiCOM P741, P742, P743 2.1.1.3.1 Sub-station features 8 values have to be known: Number of independent bus Minimum load current in a feeder Maximum load current in a feeder Maximum load current in a bus...
  • Page 177 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-11 IDN>1 (from 5 A to 500 A (primary value)), recommendation is equal to ID>1 Slope kN1 (IDN>1) (from 0% to 50%), recommendation is 5%. IDN>2 (from 50 A to 50000 A (primary value)) as high as possible Slope kN2 (IDN>2) (from 0% to 50%), recommendation is over 30%.
  • Page 178 P74x/EN AP/Na7 Application Notes (AP) 6-12 MiCOM P741, P742, P743 reinstated and after the set reset timer. 2.1.1.5 Protection options for the Check Zone 2.1.1.5.1 Options for a Circuitry Fault To block the operation of the other zones in case of internal fault during a circuitry fault in the...
  • Page 179 Central Unit via an output contact to opto input communication link. The required logic is made in the P741 PSL. The 87BB trip order can be blocked in the CU using 2 logic input sets, one to block the phase element, the second to block the SEF element and that per zone: •...
  • Page 180 P74x/EN AP/Na7 Application Notes (AP) 6-14 MiCOM P741, P742, P743 2.1.1.7 Busbar Protection Tripping Times 2.1.1.7.1 Tripping times In the P742 and P743, there are options to use a “high speed, high break” contact board. As the closing time of a standard relay is around 5ms and the operation of the high speed contact is less than 1ms, this option can be used to speed-up the tripping time by around 4ms.
  • Page 181 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-15 i DZ Trip Ibias1: DZ1 => busbar trip, Ibias2: DZ2 => no trip I>DZ Restrain I>1 i bias bias2 bias1 P3956ENa For each PU connected to a Feeder Circuit Breaker (not on bus couplers or bus sections) For the phase: •...
  • Page 182 Application Notes (AP) 6-16 MiCOM P741, P742, P743 In the main setting group (usually 1), there is no overcurrent protection, in the next setting group (usually 2) this overcurrent is enabled (on top of the same setting as in the main setting group).
  • Page 183 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-17 2.2.6.1 Application Example Example of use of high speed detectors I>2 and/or IN>2 to block the 87BB element before CT saturation 3000/5A 3000/5A 3000/5A 150/5A 150/5A 25VA 25VA 5P10 5P10 I>2 enabled...
  • Page 184 P74x/EN AP/Na7 Application Notes (AP) 6-18 MiCOM P741, P742, P743 In this example a setting of 1305 A can be used for both phase and earth faults. 2.2.7 Setting guidelines A spreadsheet tool called “FastExtThreshold” is available on request. This feature has to be used when secondary maximum current is over 50A (IN = 1A) or 250A (IN=5A) or the CT does not meet the CT requirements and if the maximum feeder contribution is far less than the maximum external fault.
  • Page 185 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-19 Since it is likely that slower baud rates will be selected, the choice of signaling mode becomes significant. However, once the signaling mode has been chosen it is necessary to consider what should happen during periods of noise when message structure and content can be lost.
  • Page 186 Peripheral Units to the central unit that undertakes scheme calculations. In the P741, a common virtual current transformer of 1000/1 A is used to convert to secondary values.
  • Page 187 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-21 CIRCUIT BREAKER FUNCTION Circuit breaker state monitoring An operator at a remote location requires a reliable indication of the state of the switchgear. Without an indication that each circuit breaker is either open or closed, the operator has insufficient information to decide on switching operations.
  • Page 188 P74x/EN AP/Na7 Application Notes (AP) 6-22 MiCOM P741, P742, P743 Resistor R1 is an optional resistor that can be fitted to prevent maloperation of the circuit breaker if the opto input is inadvertently shorted, by limiting the current to <60mA. The resistor should not be fitted for auxiliary voltage ranges of 30/34 volts or less, as satisfactory operation can no longer be guaranteed.
  • Page 189 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-23 4.2.3 TCS scheme 2 4.2.3.1 Scheme description Optional Optional P2230ENa FIGURE 4: TCS SCHEME 2 Much like scheme 1, this scheme provides supervision of the trip coil with the breaker open or closed and also does not provide pre-closing supervision.
  • Page 190 P74x/EN AP/Na7 Application Notes (AP) 6-24 MiCOM P741, P742, P743 4.2.5 TCS scheme 3 4.2.5.1 Scheme description P2231ENa FIGURE 6: TCS SCHEME 3 Scheme 3 is designed to provide supervision of the trip coil with the breaker open or closed, but unlike schemes 1 and 2, it also provides pre-closing supervision.
  • Page 191 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-25 ISOLATION AND REDUCED FUNCTION MODE The scheme permits maintenance on the busbar and, or busbar protection whilst maintaining some form of protection if possible. Two maintenance mode levels in the Central Unit and two maintenance mode levels in the Peripheral Units allow this to be possible.
  • Page 192 P74x/EN AP/Na7 Application Notes (AP) 6-26 MiCOM P741, P742, P743 Feeder In To test other protection Service relays such as Distance, Isolation to Feeder... Primary current 50/51 50BF Central Unit: Normal Trips 50BF Currents, Topology P0708ENb FIGURE 7: PU – 50BF DISABLED 5.2.2...
  • Page 193 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-27 Feeder In To test the PU & CU Service No 87 BB Isolation to At least one trip order to relevant isolator and CB ’s the CB closed 50/51 87BB&50BF...
  • Page 194 P74x/EN AP/Na7 Application Notes (AP) 6-28 MiCOM P741, P742, P743 Central processing unit (P741) A central instruction for a reduced operation mode of the busbar protection on two levels can be applied selectively zone by zone. 5.3.1 Busbar protection (87BB) Blocked The busbar protection is monitored only (not protected by 87BB) (i.e.
  • Page 195 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-29 Waiting Configuration Alarm “Config error” occurs when the configuration is incorrect: • Topology download in relay does not correspond to this relay address (be careful to erase topology by sending a default setting file) •...
  • Page 196 This topological replication is carried out from a single line diagram of the system, which is used to recreate the system using the topology configuration software. This is carried out by GE personnel at an authorised GE competence centre or by the customer for extensions after having successfully completed the dedicated training.
  • Page 197 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-31 FIGURE 11: P74x SYNOPTIC The topology configuration tool uses standard symbols for creating the system model by simply dragging and dropping in the configuration screen. Link Node Current Transformer Feeder...
  • Page 198 P74x/EN AP/Na7 Application Notes (AP) 6-32 MiCOM P741, P742, P743 • These algorithms offer flexibility to the operator not met in non-numeric conventional systems • The global substation topology is updated every 16ms The above improve the overall function and discrimination of the protection scheme and therefore reliability of the network.
  • Page 199 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-33 Topology processing The following scenarios demonstrate how the dynamic topology processing works and accommodates anomalies and discrepancies in the scheme. 6.5.1 Single bar or double bus with bus sectionaliser Bus Section Closed...
  • Page 200 P74x/EN AP/Na7 Application Notes (AP) 6-34 MiCOM P741, P742, P743 Bus Section Open Zone 1 = CT1 Isolator Closed Isolator Closed Zone 2 = CT2 Zone 1 = BB1 Zone 2 = BB2 CB Closed CB Closed Check Zone = CT1 + CT2...
  • Page 201 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-35 There is one zone for BB1 to CT3 and one zone for BB2 to CT3. CT 3 is not taken into account Zone 1 = CT1 Coupling Open Zone 2 = CT2...
  • Page 202 P74x/EN AP/Na7 Application Notes (AP) 6-36 MiCOM P741, P742, P743 A zone is defined from a CT to an other CT or an open electrical element (coupler CB or isolator). When 2 CTs are used in the coupling and the coupler CB is closed, a virtual zone is created from each bar feeder CT to the linked coupler CT.
  • Page 203 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-37 CT 4 CT 3 VZ 3 BB 2 BB 1 Coupling Closed Coupling Closed Coupling Closed Zone 1 = CT1 Isolator Closed Isolator Closed Zone 2 = CT2 Zone 1 = BB1...
  • Page 204 Application Notes (AP) 6-38 MiCOM P741, P742, P743 When 2 CTs are used in the coupling and the coupler CB is open and a coupler isolator is open, the coupler CTs measurements are not taken into account and the zone is extended from each bar feeder CT to the open CB coupler and to the open coupler isolator.
  • Page 205 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-39 6.5.5 CTs on both sides of bus coupler, CB closes before status acquisition 2 CT Coupler and CB Closes on to external fault before Status Acquisition through CB ExtFault Zone 2...
  • Page 206 P74x/EN AP/Na7 Application Notes (AP) 6-40 MiCOM P741, P742, P743 1 CT Coupler with CB closed - Fault clearance - Zone Zone diffZ1 diffZ2 fault Check zone P0703ENb = Σ i feeder = i = 0 + i diff diff Fault FIGURE 24: CT’S ON ONE SIDE OF BUS COUPLER,...
  • Page 207 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-41 1 CT Coupler with CB closed - Fault clearance - Stage 2 (zone 2 tripped but fault still present.) Zone Zone removed diffZ2 diffZ1 fault Check zone = Σ i...
  • Page 208 P74x/EN AP/Na7 Application Notes (AP) 6-42 MiCOM P741, P742, P743 6.5.7 CTs on both sides of coupler, CB closed and fault evolves between CT and CB 2 CT Coupler with the CB Closed and Fault between a CT and the CB...
  • Page 209 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-43 Check zone Idiff = I Z3 = i > (I CZ>2 + kCZ x I diff fault Bias After the coupling breaker has been tripped: Zone 1 Idiff = I7+ I8=idiffZ1 = ifault > (ID>2 + k2 x IBias) Zone 2 Idiff = I10+ I11= idiffZ2 = 0 Check zone Idiff = I7+ I8+ I10+ I11= idiffZ1 = ifault >...
  • Page 210 P74x/EN AP/Na7 Application Notes (AP) 6-44 MiCOM P741, P742, P743 UNDERTAKING A NUMERICAL DIFFERENTIAL BUSBAR PROTECTION PROJECT This Engineering must be done by a P74x Competency Centre. The substation construction will influence the protection scheme installed. It is advisable that a scheme evaluation is conducted as soon as possible, preferably at the same time as the definition of the equipment specification.
  • Page 211 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-45 Put the right addresses into the KITZs (using comms.xls) Download the complete setting files into the relays (using S1) Download the setting files into the KITZs (using comms.xls) Download the PSL files into the relays (using S1) Test the PSLs &...
  • Page 212 P74x/EN AP/Na7 Application Notes (AP) 6-46 MiCOM P741, P742, P743 • Compensated: − Minimum two phase busbar fault current − Maximum single-phase steady state busbar fault current − Maximum load current on the biggest feeder − Optional: Maximum three phase busbar fault current •...
  • Page 213 REVOLVING DOOR FIXED FRAME FIXED FRAME FIGURE 28: 1 P741 AND P743 WITH (OR WITHOUT) P99X TEST BLOCK Substation Architecture Due to the flexibility of the differential busbar protection there is an infinite number of busbar configurations that can be accommodated via the topology. Each may have very different architecture and, therefore, vary in complexity.
  • Page 214 STANDARD CONFIGURATIONS The following information relates only to the more common standard schemes. For further information on the accommodation of other busbar configurations consult your GE representative. The main rule to calculate the minimum number of Peripheral Unit to use is: 1 Peripheral Unit per CT.
  • Page 215 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-49 P3783ENa FIGURE 30: SINGLE BUSBAR APPLICATION WITH BUS SECTION CIRCUIT BREAKER The above example shows a single busbar with a bus section circuit breaker. It is split into two zones. There are n feeders connected to the busbar. The bus section circuit breaker has CTs on either side.
  • Page 216 P74x/EN AP/Na7 Application Notes (AP) 6-50 MiCOM P741, P742, P743 P3784ENa FIGURE 31: BREAKER AND A HALF SCHEME The above example shows a breaker and a half scheme. The recommended solution is to have two separate schemes. There are n feeders connected to each busbar.
  • Page 217 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-51 The above example shows a double busbar with a bus coupler. It is split into two zones. There are n feeders connected to the busbar. The bus coupler circuit breaker can have either a single CT (solution 1) on one side or CTs on both sides (solution 2).
  • Page 218 P74x/EN AP/Na7 Application Notes (AP) 6-52 MiCOM P741, P742, P743 Solution Solution Solution Solution Solution 1 CT on BC 2 CT on BC 1 CT on BC 2 CT on BC & 1 CT on BS & 2 CT on BS &...
  • Page 219 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-53 Solution Solution A Solution B Solution C Solution D 1 CT on BC 2 CT on BC 1 CT on BC 2 CT on BC & 1 CT on BS &...
  • Page 220 P74x/EN AP/Na7 Application Notes (AP) 6-54 MiCOM P741, P742, P743 Solution Solution A Solution B Solution C Solution D 1 CT on BC 2 CT on BC 1 CT on BC 2 CT on BC & 1 CT on & 2 CT on &...
  • Page 221 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-55 It is split into two zones. There are n feeders connected to the busbar. The bus coupler circuit breaker can have either a single CT (solution 1) on one side or CTs on both sides (solution 2).
  • Page 222 P74x/EN AP/Na7 Application Notes (AP) 6-56 MiCOM P741, P742, P743 P3791ENa FIGURE 38: TRIPLE BUSBAR APPLICATION WITH BUS COUPLER AND BUS SECTION The above example shows a triple busbar with both a bus section and a bus coupler. bus section also has additional bus section isolators and allows for bus section bypass. The scheme is split into six zones.
  • Page 223 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-57 The number of additional peripheral units being dependant on the number of bus section/bus coupler CTs. The type of peripheral unit used for each bay will depend on the i/o requirements of the bay in question.
  • Page 224 P74x/EN AP/Na7 Application Notes (AP) 6-58 MiCOM P741, P742, P743 The above example shows a mesh corner arrangement. The scheme is split into four zones. This configuration requires 1 central unit and 12 peripheral units. P3794ENa FIGURE 41: SIX MAIN BUS FOR S/S CB BUS-SECTIONS AND CB BY-PASS The above example shows a six busbar arrangement with both a bus section and a bus coupler.
  • Page 225 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-59 Solution Solution A Solution B Solution C Solution D 1 CT on BC 2 CT on BC 1 CT on BC 2 CT on BC & 1 CT on & 2 CT on &...
  • Page 226 P74x/EN AP/Na7 Application Notes (AP) 6-60 MiCOM P741, P742, P743 APPLICATION OF NON PROTECTION FUNCTIONS The non-protection features for the scheme are summarised below: • Scheme can be centralised/distributed – if space is not available to locate the busbar protection centrally it is possible to decentralise the scheme and locate the units within other protection cubicles •...
  • Page 227 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-61 Function Keys 4 and 5 are set to ‘Toggle’ mode and on activation of the key, the commissioning mode will be in service as long as the function has been enabled in the “Configuration”...
  • Page 228 P74x/EN AP/Na7 Application Notes (AP) 6-62 MiCOM P741, P742, P743 CT REQUIREMENTS 10.1 Notation max fault maximum fault current (same for all feeders) in A max int maximum contribution from a feeder to an internal fault (depends on the cont...
  • Page 229 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-63 10.2.3 CT Specification according to IEC 185, 44-6 and BS 3938 (British Standard) Class X according to British Standard: Minimum knee point voltage for saturation min = 0.5 x secondary I...
  • Page 230 P74x/EN AP/Na7 Application Notes (AP) 6-64 MiCOM P741, P742, P743 10.3 87BB Sensitive Differential Earth Fault CT Requirements The Sensitive Differential Earth Fault (SDEF) shall be enabled only on High Impedance Earthed Networks. To enable the SDEF the CTs have to comply with the additional following requirement: min = 1.5 x X/R x I...
  • Page 231 Application Notes P74x/EN AP/Na7 MiCOM P741, P742, P743 (AP) 6-65 Where: = Equivalent IEC or BS knee point voltage = C Rating = 5A = CT secondary winding resistance Kssc = 20 times...
  • Page 232 P74x/EN AP/Na7 Application Notes (AP) 6-66 MiCOM P741, P742, P743 AUXILIARY SUPPLY FUSE RATING In the Safety section of this manual, the maximum allowable fuse rating of 16A is quoted. To allow time grading with fuses upstream, a lower fuselink current rating is often preferable.
  • Page 233 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 PROGRAMMABLE LOGIC Hardware Suffix: J and K Software Version:...
  • Page 234 P74x/EN PL/Na7 Programmable Logic MiCOM P741, P742, P743...
  • Page 235 1.6.14 LED conditioner properties 1.6.15 Contact conditioner properties 1.6.16 Timer properties 1.6.17 Gate properties Description of P741 logic nodes 1.7.1 Sorted by DDB number 1.7.2 Sorted by DDB name Description of P742 logic nodes 1.8.1 Sorted by DDB number 1.8.2...
  • Page 236 P74x/EN PL/Na7 Programmable Logic (PL) 7-2 MiCOM P741, P742, P743 1.12 Relay output contact mapping 1.13 Function key input mapping 1.14 Programmable LED output mapping 1.15 Fault recorder start mapping 1.16 PSL DATA column P741 PROGRAMMABLE SCHEME LOGIC P742 PROGRAMMABLE SCHEME LOGIC...
  • Page 237 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-3 PROGRAMMABLE LOGIC Overview The purpose of the programmable scheme logic (PSL) is to allow the relay user to configure an individual protection scheme to suit their own particular application. This is achieved through the use of programmable logic gates and delay timers.
  • Page 238 P74x/EN PL/Na7 Programmable Logic (PL) 7-4 MiCOM P741, P742, P743 How to use Px40 PSL editor With the Px40 PSL Module you can: • Start a new PSL diagram • Extract a PSL file from a Px40 IED • Open a diagram from a PSL file •...
  • Page 239 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-5 Toolbar and commands There are a number of toolbars available for easy navigation and editing of PSL. 1.5.1 Standard tools • For file management and printing. 1.5.2 Alignment tools •...
  • Page 240 P74x/EN PL/Na7 Programmable Logic (PL) 7-6 MiCOM P741, P742, P743 Link Create a link between two logic symbols. Opto Signal Create an opto signal. Input Signal Create an input signal. Output Signal Create an output signal. GOOSE In Create an input signal to logic to receive a GOOSE message transmitted from another IED.
  • Page 241 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-7 PSL logic signals properties The logic signal toolbar is used for the selection of logic signals. Performing a right-mouse click on any logic signal will open a context sensitive menu and one of the options for certain logic elements is the Properties…...
  • Page 242 P74x/EN PL/Na7 Programmable Logic (PL) 7-8 MiCOM P741, P742, P743 1.6.3 Input signal properties Input Signal Relay logic functions provide logic output signals that can be used for programming in PSL. Depending on the relay functionality, operation of an active relay function will drive an associated DDB signal in PSL.
  • Page 243 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-9 1.6.7 Control in signal properties Control In There are 32 control inputs which can be activated via the relay menu, ‘hotkeys’ or via rear communications. Depending on the programmed setting i.e. latched or pulsed, an associated DDB signal will be activated in PSL when a control input is operated.
  • Page 244 P74x/EN PL/Na7 Programmable Logic (PL) 7-10 MiCOM P741, P742, P743 1.6.12 LED signal properties All programmable LEDs will drive associated DDB signal when the LED is activated. For example DDB 652 will be asserted when LED 7 is activated. 1.6.13...
  • Page 245 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-11 1.6.15 Contact conditioner properties Each contact can be conditioned with an associated timer that can be selected for pick up, drop off, dwell, pulse, pick-up/drop-off, straight-through, or latching operation. “Straight-through” means it is not conditioned in any way whereas “latching” is used to create a sealed-in or lockout type function.
  • Page 246 P74x/EN PL/Na7 Programmable Logic (PL) 7-12 MiCOM P741, P742, P743 1.6.17 Gate properties A Gate may be an AND, OR, programmable gate or SR Latch . An AND gate requires that all inputs are TRUE for the output to be TRUE.
  • Page 247 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-13 Standard no change / last state no change / last state Set Input Dominant no change / last state Reset Input Dominant no change / last state P0737ENa 1. Select the Gate type AND, OR, or Programmable.
  • Page 248 P74x/EN PL/Na7 Programmable Logic (PL) 7-14 MiCOM P741, P742, P743 Description of P741 logic nodes 1.7.1 Sorted by DDB number: Relay English Text Type Source Description P741 Relay Label 01 RELAY Output Conditioner Output Relay 01 P741 Relay Label 08...
  • Page 249 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-15 Relay English Text Type Source Description P741 Ext Trip 50BF z8 PSL Output PSL (50BF External Breaker failure trip order (50BF) of Signal Backtrip protection) zone 8 opto input P741...
  • Page 250 P74x/EN PL/Na7 Programmable Logic (PL) 7-16 MiCOM P741, P742, P743 Relay English Text Type Source Description P741 PU Error Lock CZ PSL Input Signal Scheme Integrity PU error blocking the Check Zone P741 Err Chan 1 Com A PSL Input Signal...
  • Page 251 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-17 Relay English Text Type Source Description P741 Battery Fail PSL Input Signal Relay Integrity Front panel Battery Failure P741 Field Voltage Fail PSL Input Signal Relay Integrity 48V Field Voltage Failure...
  • Page 252 P74x/EN PL/Na7 Programmable Logic (PL) 7-18 MiCOM P741, P742, P743 Relay English Text Type Source Description P741 FnKey LED 10 TRI_LED PSL (LED) Programmable Function Key LED 10 Green is energized P741 Function Key 1 FUNCTION_KEY PSL (Function Key) Function Key 1 is activated. In ‘Normal’ mode it is high on key press and in ‘Toggle’...
  • Page 253 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-19 Relay English Text Type Source Description P741 87BB Ph Diff z1 PSL Input Signal 87BB fault detected in zone 1 by the phase differential element P741 87BB Ph Diff z8...
  • Page 254 P74x/EN PL/Na7 Programmable Logic (PL) 7-20 MiCOM P741, P742, P743 Relay English Text Type Source Description P741 Ext Start DR PSL Output Starting Disturbance Recorder Signal P741 Ext Trip 50BF PSL Input Signal 50BF Backtrip 50BF backtrip request by opto input...
  • Page 255 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-21 Relay English Text Type Source Description P741 INP Lck Lev.1 z8 PSL Output Maintenance Mode 1 (87BB monitoring) of zone Signal (Commissioning) 8 opto input P741 INP Lck Lev.2 z1 PSL Output Maintenance Mode 2 (50BF &...
  • Page 256 P74x/EN PL/Na7 Programmable Logic (PL) 7-22 MiCOM P741, P742, P743 Relay English Text Type Source Description P741 PU Error Alm z8 PSL Input Signal Scheme Integrity PU error alarm in zone 8 P741 PU Error Alm Zx PSL Input Signal...
  • Page 257 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-23 Relay English Text Type Source Description P741 1087 virtual input 64 GOOSEIN GOOSE Input Virtual Input 64 Command Allows binary signals that are mapped to virtual inputs to interface into PSL...
  • Page 258 P74x/EN PL/Na7 Programmable Logic (PL) 7-24 MiCOM P741, P742, P743 Relay English Text Type Source Description P742 Sett Grp Bit LSB PSL Output Setting Group Selector X1 (low bit) Signal SG1 is active DDB 104=0 & DDB 105=0 SG2 is active DDB 104=1 & DDB 105=0...
  • Page 259 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-25 Relay English Text Type Source Description P742 Zone 8 Off PSL Input Signal CU Information Zone 8 in commissioning mode or blocked by a Circuitry fault or a PU error...
  • Page 260 P74x/EN PL/Na7 Programmable Logic (PL) 7-26 MiCOM P741, P742, P743 Relay English Text Type Source Description P742 Dead Zone Fault PSL Input Signal Local Protection Fault in the dead zone P742 Dead Zone PSL Input Signal Local Protection Fault in the dead zone on a phase...
  • Page 261 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-27 Relay English Text Type Source Description P742 CB Trip 3 ph PSL Input Signal 50BF Protection Triphase Circuit Breaker Trip from CU (Init 50BF TBF1 / TBF2), Logical OR of :...
  • Page 262 P74x/EN PL/Na7 Programmable Logic (PL) 7-28 MiCOM P741, P742, P743 Relay English Text Type Source Description P742 CBF I> Start B PSL Output 50BF Protection Phase B overcurrent CBF Dead Pole Start Signal P742 CBF I> Start C PSL Output...
  • Page 263 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-29 Relay English Text Type Source Description P742 CB Aux. B (52b) PSL Output 52-B (CB open) CB Auxiliary Input (Phase B) Signal P742 CB Aux. C (52a) PSL Output 52-A (CB closed) CB Auxiliary Input (phase C)
  • Page 264 P74x/EN PL/Na7 Programmable Logic (PL) 7-30 MiCOM P741, P742, P743 Relay English Text Type Source Description P742 CU->PU Signal PSL Input Signal Virtual Signal 16 from the CU to the PU via the fibre optic P742 Current Overflow PSL Input Signal...
  • Page 265 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-31 Relay English Text Type Source Description P742 I>BB Start C PSL Input Signal Phase Overcurrent Local overcurrent phase C Trip confirmation for 87BB or 50BF (CU) trip order P742 IN>1 Start...
  • Page 266 P74x/EN PL/Na7 Programmable Logic (PL) 7-32 MiCOM P741, P742, P743 Relay English Text Type Source Description P742 1280 PubPres VIP 1 PSL Input Signal Publishing presence of virtual input 1: indicates virtual input 1 presence. P742 1343 PubPres VIP 64...
  • Page 267 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-33 Relay English Text Type Source Description P742 Topo/Set PSL Input Signal Commissioning Change on topology or configuration Changed P742 Topo/Set valid PSL Input Signal Scheme Integrity Wrong Topology address P742...
  • Page 268 P74x/EN PL/Na7 Programmable Logic (PL) 7-34 MiCOM P741, P742, P743 Relay English Text Type Source Description P743 CB Aux. 3ph(52a) PSL Output 52-A (CB closed) Signal CB Auxiliary Input (3 phase) P743 CB Aux. 3ph(52b) PSL Output 52-B (CB open)
  • Page 269 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-35 Relay English Text Type Source Description P743 IN>2 Trip PSL Input Signal Earth Fault 2nd Stage Earth Fault Trip P742 I>1 Timer Block PSL Input Signal Blocking of the 1...
  • Page 270 P74x/EN PL/Na7 Programmable Logic (PL) 7-36 MiCOM P741, P742, P743 Relay English Text Type Source Description P743 Man.Trip zone PSL Input Signal Commissioning Manual Trip Order of a zone, general information common to all PUs, the PU can be connected to an healthy zone...
  • Page 271 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-37 Relay English Text Type Source Description P743 CB Trip phase A PSL Input Signal 50BF Protection Phase A Circuit Breaker Trip (Init 50BF TBF3 / TBF4), Logical OR of :...
  • Page 272 P74x/EN PL/Na7 Programmable Logic (PL) 7-38 MiCOM P741, P742, P743 Relay English Text Type Source Description P743 IM Data CD Fail PSL Input Signal InterMiCOM InterMiCOM Data Channel Detect Fail P743 IM Channel Fail PSL Input Signal InterMiCOM InterMiCOM Channel Failure Alarm...
  • Page 273 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-39 Relay English Text Type Source Description P743 LED 8 Grn Condit TRI_LED_CON Output Conditioner Assignment of signal to drive output LED 8 Green. To drive LED8 Yellow DDB 778 and DDB 779...
  • Page 274 P74x/EN PL/Na7 Programmable Logic (PL) 7-40 MiCOM P741, P742, P743 Relay English Text Type Source Description P743 CB Aux. A (52a) PSL Output Signal 52-A (CB closed) CB Auxiliary Input (phase A) P743 CB Aux. A (52b) PSL Output Signal...
  • Page 275 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-41 Relay English Text Type Source Description P743 Current Overflow PSL Input Signal Saturation Fibre optic Maximum primary current encoding exceeded P743 Dead Zone Earth PSL Input Signal Local Protection Fault in the dead zone on the neutral...
  • Page 276 P74x/EN PL/Na7 Programmable Logic (PL) 7-42 MiCOM P741, P742, P743 Relay English Text Type Source Description P743 GOOSE OUT 32 GOOSEOUT GOOSE Output 32 Allows user to control a binary signal which can be mapped via SCADA protocol output to other...
  • Page 277 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-43 Relay English Text Type Source Description P743 LED 1 Grn Condit TRI_LED_CON Output Conditioner Assignment of signal to drive output LED 1Green. To drive LED1 Yellow DDB 764 and DDB 765 must...
  • Page 278 P74x/EN PL/Na7 Programmable Logic (PL) 7-44 MiCOM P741, P742, P743 Relay English Text Type Source Description P743 Q6 Status Alarm PSL Output Signal Scheme Integrity Isolator 6 discrepancy (Q6 Aux. (89b) = Q6 Aux. (89a) for too long P743 Q6 Status Forced...
  • Page 279 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-45 Relay English Text Type Source Description P743 Zone 1 Off PSL Input Signal CU Information Zone 1 in commissioning mode or blocked by a Circuitry fault or a PU error...
  • Page 280 P74x/EN PL/Na7 Programmable Logic (PL) 7-46 MiCOM P741, P742, P743 1.10 Factory default programmable scheme logic The following section details the default settings of the PSL. The P74x models are as follows: Model Logic Inputs Relay Outputs P741xxxAxxxxxxK P742xxxAxxxxxxJ P742xxxBxxxxxxJ...
  • Page 281 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-47 Opto-Input P74x Relay Text Function Number Input Label 15 Manual CB close command Input Label 16 Mode Overhaul Peripheral Unit P743: Opto-Input P74x Relay Text Function Number Input Label 01...
  • Page 282 P74x/EN PL/Na7 Programmable Logic (PL) 7-48 MiCOM P741, P742, P743 1.12 Relay output contact mapping The default mappings for each of the relay output contacts are as shown in the following table: Central Unit P741: Relay P74x Relay Contact P74x Relay Text...
  • Page 283 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-49 Peripheral Unit P743: Relay P74x Relay Contact P74x Relay Text Function Conditioner Number Relay Label 01 Pick-up 0/0 Trip 87BB or 50BF backtrip (fixed) Relay Label 02 Pick-up 0/0 Trip 87BB or 50BF backtrip (fixed)
  • Page 284 P74x/EN PL/Na7 Programmable Logic (PL) 7-50 MiCOM P741, P742, P743 Peripheral Unit P743: Text Setting Function Number FnKey 1 Normal To reset the Latches FnKey 2 Normal To reset the Trip Latch FnKey 3 Not Used Not used FnKey 4...
  • Page 285 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-51 LED Input Connection/Text Latched P74x LED Function Indication Number LED8 Red Fiber communication Error LED8 Yellow Fiber communication to change LED8 Green Fiber communication healthy FnKey LED1 Red Zone or CZ circuitry fault block.
  • Page 286 P74x/EN PL/Na7 Programmable Logic (PL) 7-52 MiCOM P741, P742, P743 Peripheral Unit P742: LED Input Connection/Text Latched P74x LED Function Indication Number LED 1 Red Isolator 1 Closed LED 2 Red Isolator 2 Closed LED 3 Red Isolator 3 Closed...
  • Page 287 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-53 LED Input Connection/Text Latched P74x LED Function Indication Number FnKey LED2 Red Not used FnKey LED2 Yellow Not used FnKey LED2 Green Reset PU Trip Latch FnKey LED3 Red FnKey LED3 Yellow...
  • Page 288 P74x/EN PL/Na7 Programmable Logic (PL) 7-54 MiCOM P741, P742, P743 1.15 Fault recorder start mapping The default mapping for the signal which initiates a fault record is as shown in the following table: Central Unit (P741): Initiating Signal Fault Trigger...
  • Page 289 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-55 P741 PROGRAMMABLE SCHEME LOGIC...
  • Page 290 P74x/EN PL/Na7 Programmable Logic (PL) 7-56 MiCOM P741, P742, P743...
  • Page 291 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-57...
  • Page 292 P74x/EN PL/Na7 Programmable Logic (PL) 7-58 MiCOM P741, P742, P743...
  • Page 293 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-59 P742 PROGRAMMABLE SCHEME LOGIC...
  • Page 294 P74x/EN PL/Na7 Programmable Logic (PL) 7-60 MiCOM P741, P742, P743...
  • Page 295 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-61...
  • Page 296 P74x/EN PL/Na7 Programmable Logic (PL) 7-62 MiCOM P741, P742, P743...
  • Page 297 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-63 P743 PROGRAMMABLE SCHEME LOGIC...
  • Page 298 P74x/EN PL/Na7 Programmable Logic (PL) 7-64 MiCOM P741, P742, P743...
  • Page 299 Programmable Logic P74x/EN PL/Na7 MiCOM P741, P742, P743 (PL) 7-65...
  • Page 300 P74x/EN PL/Na7 Programmable Logic (PL) 7-66 MiCOM P741, P742, P743...
  • Page 301 Measurements and Recording P74x/EN MR/Na7 MiCOM P741, P742, P743 MEASUREMENTS AND RECORDING Hardware Suffix: J and K Software Version:...
  • Page 302 P74x/EN MR/Na7 Measurements and Recording MiCOM P741, P742, P743...
  • Page 303 Setting changes Resetting of event/fault records Viewing event records via S1 support software Event filtering DISTURBANCE RECORDER “Disturb recorder” column – Central Unit P741 “Disturb recorder” column – Peripheral Unit P742 or P743 MEASUREMENTS Check Zone Phase Currents Measured currents...
  • Page 304 P74x/EN MR/Na7 Measurements and Recording (MR) 8-2 MiCOM P741, P742, P743 MONITORING TOOLS Dynamic Synoptic...
  • Page 305 Measurements and Recording P74x/EN MR/Na7 MiCOM P741, P742, P743 (MR) 8-3 INTRODUCTION The P74x is equipped with integral measurements, event, fault and disturbance recording facilities suitable for analysis of complex system disturbances. The relay is flexible enough to allow for the programming of these facilities to specific user...
  • Page 306 P74x/EN MR/Na7 Measurements and Recording (MR) 8-4 MiCOM P741, P742, P743 EVENT & FAULT RECORDS The relay records and time tags up to 512 events and stores them in non-volatile (battery backed up) memory. This enables the system operator to establish the sequence of events that occurred within the relay following a particular power system condition, switching sequence etc.
  • Page 307 Measurements and Recording P74x/EN MR/Na7 MiCOM P741, P742, P743 (MR) 8-5 VIEW RECORDS Description LCD Reference IA diff Differential current of the check zone IB diff Differential current of the check zone IC diff Differential current of the check zone...
  • Page 308 P74x/EN MR/Na7 Measurements and Recording (MR) 8-6 MiCOM P741, P742, P743 VIEW RECORDS Description LCD Reference Start Elements Start I>1, Start I>2, Start I>2BB, Start I>BB, Start IN>1, Start IN>2, Start IN>2BB, Start IN>BB Trip Elements Trip I>1, Trip I>2, Trip IN>1, Trip IN>2, Trip 87BB, Trip...
  • Page 309 Measurements and Recording P74x/EN MR/Na7 MiCOM P741, P742, P743 (MR) 8-7 The Event Value is a 12, 16, 24 or 32-bit word showing the status of the opto inputs, where the least significant bit (extreme right) corresponds to opto input 1 etc.
  • Page 310 P74x/EN MR/Na7 Measurements and Recording (MR) 8-8 MiCOM P741, P742, P743 Alarm P741 P742 P743 Bit 16 PU Error Lck CZ Q1 Status Alarm Q1 Status Alarm Bit 17 Config Error Q2 Status Alarm Q2 Status Alarm Bit 18 User Alarm 1...
  • Page 311 Measurements and Recording P74x/EN MR/Na7 MiCOM P741, P742, P743 (MR) 8-9 Alarm P741 P742 P743 Bit 2 Unused Unused Unused GOOSE IED Bit 3 Absent Unused GOOSE IED Absent Bit 4 NIC Not Fitted Unused NIC Not Fitted Bit 5...
  • Page 312 The fault record is triggered from the ‘Fault REC. TRIG.’ signal assigned in the default programmable scheme logic to any trip (87BB or 50BF trip in the P741). Note the fault measurements in the fault record are given at the time of the protection start. Also, the fault recorder does not stop recording until the reset of the ‘Fault REC.
  • Page 313 When the event records are extracted and viewed on a PC they look slightly different than when viewed on the LCD. The following shows a P741 example of how various events appear when displayed using The following shows a P742 example of how various events appear when displayed using...
  • Page 314 Measurements and Recording (MR) 8-12 MiCOM P741, P742, P743 As can be seen, the first line gives the description and time stamp for the event, whilst the additional information that is displayed below may be collapsed via the +/– symbol.
  • Page 315 Measurements and Recording P74x/EN MR/Na7 MiCOM P741, P742, P743 (MR) 8-13 Event filtering It is possible to disable the reporting of events from all interfaces that supports setting changes. The settings that control the various types of events are in the “record control”...
  • Page 316 The "DISTURB RECORDER" menu columns are presented in the “Settings” section P74x/EN ST. The following tables give default setting configuration for central and peripheral units. “Disturb recorder” column – Central Unit P741 Menu Text Default Setting Explanation...
  • Page 317 Measurements and Recording P74x/EN MR/Na7 MiCOM P741, P742, P743 (MR) 8-15 Menu Text Default Setting Explanation Digital input 15 Trip 50BF zone 1 Trip 50BF zone 1 digital channel Digital input 16 Trip 50BF zone 2 Trip 50BF zone 2 digital channel...
  • Page 318 P74x/EN MR/Na7 Measurements and Recording (MR) 8-16 MiCOM P741, P742, P743 Menu Text Default Setting Explanation Input 12 trigger No Trigger Digital input 13 Q2 Closed Isolator 2 closed digital channel Input 13 trigger No Trigger Digital input 14 Q3 Closed...
  • Page 319 These measurement values are updated on a per second basis and can be viewed in the “Measurements” columns (up to three) of the relay or via S1 Measurement viewer. The P741 relay is able to measure and display the following quantities as summarized. Check Zone Phase Currents There are also measured values from the protection functions, which are also displayed under the measurement columns of the menu;...
  • Page 320 P74x/EN MR/Na7 Measurements and Recording (MR) 8-18 MiCOM P741, P742, P743 MEASUREMENTS 1 MEASUREMENTS 2 TOPOLOGY 1 TOPOLOGY 2 Z02 : IC bias Z02 : IN bias … Z08 : IA diff Z08 : IB diff Z08 : IC diff...
  • Page 321 MONITORING TOOLS The embedded standard S1 Software monitoring is designed for 8 zones substation. Consequently, if you open connection with P741 which protects 4 zones substation, there are error messages to inform you that cells corresponding to topology and measurements of zone 5 to 8 can not be displayed.
  • Page 322 P74x/EN MR/Na7 Measurements and Recording (MR) 8-20 MiCOM P741, P742, P743 FIGURE 1: CONNECTED TO THE CENTRAL UNIT FIGURE 2: CONNECTED TO A PERIPHERAL UNIT...
  • Page 323 Firmware Design P74x/EN FD/Na7 MiCOM P741, P742, P743 FIRMWARE DESIGN Hardware Suffix: J and K Software Version:...
  • Page 324 P74x/EN FD/Na7 Firmware Design MiCOM P741, P742, P743...
  • Page 325 1.1.5 Input and output boards 1.1.6 Power supply module 1.1.7 IRIG-B board 1.1.8 Second rear comms and EIA(RS)232 InterMiCOM board (optional) (P741 and P743) 1.1.9 Ethernet or redundant Ethernet board (P741 and P743) Software overview 1.2.1 Real-time operating system 1.2.2 System services software 1.2.3...
  • Page 326 Overview - protection and control scheduling 3.5.2 Topology software 3.5.3 Signal processing 3.5.4 Programmable scheme logic 3.5.5 Function key interface (P741 and P743) 3.5.6 Event and fault recording 3.5.7 Disturbance recorder SELF TESTING & DIAGNOSTICS Start-up self-testing 4.1.1 System boot 4.1.2...
  • Page 327 In P742 and P743, the co-processor board controls the operation of I/O modules within the relay and manages the communication with the P741 relay. In P741, the co-processor board controls the communication boards and manages the communication with others P741 of the system (if present).
  • Page 328 This board, which is optional, can be used where an IRIG-B signal is available to provide an accurate time reference for the relays (P741, P742 and P743). The IRIG-B board can only be used in P741 relay and is controlled by the main board.
  • Page 329 FIGURE 2: P742 & P743 ARCHITECTURE 1.1.8 Second rear comms and EIA(RS)232 InterMiCOM board (optional) (P741 and P743) The optional second rear port is designed typically for dial-up modem access by protection engineers/operators, when the main port is reserved for SCADA traffic. Communication is via...
  • Page 330 Ethernet and redundant Ethernet boards are mandatory boards for IEC 61850 enabled relays. The boards provide network connectivity through either copper or fiber media at rates of 10Mb/s (copper only) or 100Mb/s. There is also an option on the Ethernet board (P741) to specify IRIG-B board port (modulated or un-modulated).
  • Page 331 Firmware Design P74x/EN FD/Na7 MiCOM P741, P742, P743 (FD) 9-7 FIGURE 3: SOFTWARE OVERVIEW 1.2.1 Real-time operating system As explain in the hardware overview, each relay contains one main board and one coprocessor board. These two boards use two different operating system: •...
  • Page 332 P74x/EN FD/Na7 Firmware Design (FD) 9-8 MiCOM P741, P742, P743 FIGURE 4: RELAY MODULES AND INFORMATION FLOW 1.2.2 System services software The system services software provides the low-level control of the relay hardware. For example, the system services software controls the boot of the relay’s software from the non-volatile flash EPROM memory at power-on, and provides driver software for the user interface via the LCD and keypad, and via the serial communication ports.
  • Page 333 Firmware Design P74x/EN FD/Na7 MiCOM P741, P742, P743 (FD) 9-9 1.2.3 Platform software The platform software deals with the management of the relay settings, the user interfaces and logging of event, alarm, fault and maintenance records. All of the relay settings are stored in a database within the relay that provides direct compatibility with Courier communications.
  • Page 334 When software starts, the microprocessor configures the board. After this, optical communication can begin. In P741 relay, coprocessor board controls 1 opto board, 1 relay board and up to 7 communication boards via its own interconnection bus. In P742 and P743 relays, coprocessor board controls opto boards and relay boards via its own interconnection bus.
  • Page 335 This board is only used within P741 relay. It performs the communication with the P742 and P743 relays. Up to 7 communication boards can be interfaced within P741 relay. So up to 28 P742 or P743 relays can be interfaced from a P741 relay.
  • Page 336 The input module consists of two PCBs; the main input board and a transformer board. The P742 and P743 provide four current inputs (3 phases and neutral). P741 relay don’t use this board. FIGURE 5: MAIN INPUT BOARD...
  • Page 337 Firmware Design P74x/EN FD/Na7 MiCOM P741, P742, P743 (FD) 9-13 2.5.1 Transformer board The transformer board holds four voltage transformers (VTs) and four current transformers (CTs). The current inputs will accept either 1A or 5A nominal current (menu and wiring options) and the voltage inputs can be specified for either 110V or 440V nominal voltage (order option).
  • Page 338 2.5.3 Universal opto isolated logic inputs The P741, P742 and P743 relays are fitted with universal opto isolated logic inputs that can be programmed for the nominal battery voltage of the circuit of which they are a part. i.e. thereby allowing different voltages for different circuits e.g. signalling, tripping. They nominally provide a Logic 1 or "ON"...
  • Page 339 Firmware Design P74x/EN FD/Na7 MiCOM P741, P742, P743 (FD) 9-15 All internal communication of data from the power supply board is conducted via the output relay board which is connected to the parallel bus. The watchdog facility provides two output relay contacts, one normally open and one normally closed that are driven by the processor board.
  • Page 340 2.11 IRIG-B board (in P741) The IRIG-B board is an order option that can be fitted in the P741 to provide an accurate timing reference for the relays (P741, P742 and P743 (via the P741)). This is available as a modulated or de-modulated option depending on the requirements.
  • Page 341 100 Mbits/s Fiber Optic + 10/100 Mbits/s Copper for P741 and P743 • 100 Mbits/s Fiber Optic + 10/100 Mbits/s Copper + modulated IRIG-B for P741 only • 100 Mbits/s Fiber Optic + 10/100 Mbits/s Copper + demodulated IRIG-B for P741 only...
  • Page 342 P74x/EN FD/Na7 Firmware Design (FD) 9-18 MiCOM P741, P742, P743 RELAY SOFTWARE The relay software was introduced in the overview of the relay at the start of this manual (P74x/EN FD). The software can be considered to be made up of five sections: •...
  • Page 343 Firmware Design P74x/EN FD/Na7 MiCOM P741, P742, P743 (FD) 9-19 Real-time operating system • Real-time operating system for main board: the real-time operating system is used to schedule the processing of the tasks to ensure that they are processed in the time available and in the desired order of priority.
  • Page 344 P74x/EN FD/Na7 Firmware Design (FD) 9-20 MiCOM P741, P742, P743 FIGURE 10: P74x SYSTEM OVERVIEW...
  • Page 345 Firmware Design P74x/EN FD/Na7 MiCOM P741, P742, P743 (FD) 9-21 Platform software The platform software has three main functions: • To control the logging of records that are generated by the protection software, including alarms and event, fault, and maintenance records.
  • Page 346 3.5.1 Overview - protection and control scheduling Figure 2 shows parts of the GE software and their allocation on the different boards of the peripheral and central units. The P74x relays contained two global protections, busbar protection and circuit breaker failure, and one local function, overcurrent protection.
  • Page 347 PSL is implemented through the PC support package S1. 3.5.5 Function key interface (P741 and P743) The ten function keys interface directly into the PSL as digital input signals and are processed based on the PSL’s event driven execution. However, a change of state is only recognized when a key press is executed on average for longer than 200 ms.
  • Page 348 P74x/EN FD/Na7 Firmware Design (FD) 9-24 MiCOM P741, P742, P743 3.5.7 Disturbance recorder The disturbance recorder operates as a separate task from the protection and control task. It can record the waveforms for up to 8 analogue channels and the values of up to 32 digital signals.
  • Page 349 Firmware Design P74x/EN FD/Na7 MiCOM P741, P742, P743 (FD) 9-25 SELF TESTING & DIAGNOSTICS The relay includes a number of self-monitoring functions to check the operation of its hardware and software when it is in service. These are included so that if an error or fault occurs within the relay’s hardware or software, the relay is able to detect and report the...
  • Page 350 P74x/EN FD/Na7 Firmware Design (FD) 9-26 MiCOM P741, P742, P743 4.1.3 Platform software initialization & monitoring In starting the platform software, the relay checks the integrity of the data held in non-volatile memory with a checksum, the operation of the real-time clock, and the IRIG-B board if fitted.
  • Page 351 Firmware Design P74x/EN FD/Na7 MiCOM P741, P742, P743 (FD) 9-27...
  • Page 352 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 COMMISSIONING Hardware Suffix: J and K Software Version:...
  • Page 353 P74x/EN CM/Na7 Commissioning MiCOM P741, P742, P743...
  • Page 354 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-1 CONTENTS INTRODUCTION SETTING FAMILIARISATION EQUIPMENT REQUIRED FOR COMMISSIONING Minimum equipment required Optional equipment PRODUCT CHECKS With the relay de-energised 4.1.1 Visual inspection 4.1.2 Current transformer shorting contacts 4.1.3 Insulation 4.1.4 External wiring 4.1.5...
  • Page 355 P74x/EN CM/Na7 Commissioning (CM) 10-2 MiCOM P741, P742, P743 END TO END TESTS ON-LOAD CHECKS FINAL CHECKS COMMISSIONING TEST RECORD 10.1 Peripheral Units: P742/P743 SETTING RECORD 11.1 Central Unit: P741 11.1.1 Relays Setting configuration 11.1.2 Disturbance recorder settings 11.1.3 Control and support settings 11.1.4...
  • Page 356 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-3 INTRODUCTION The P74x Busbar Differential Protection is fully numerical in their design, implementing all protection and non-protection functions in software. The relays employ a high degree of self- checking and, in the unlikely event of a failure, will give an alarm. As a result the commissioning tests do not need to be as extensive as with non-numeric electronic or electromechanical relays.
  • Page 357 P74x/EN CM/Na7 Commissioning (CM) 10-4 MiCOM P741, P742, P743 SETTING FAMILIARISATION When commissioning a P74x Busbar protection for the first time, sufficient time should be allowed to become familiar with the method by which the settings are applied. The Introduction (P74x/EN IT) contains a detailed description of the menu structure of P74x relays.
  • Page 358 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-5 EQUIPMENT REQUIRED FOR COMMISSIONING Minimum equipment required Overcurrent test set with interval timer Multimeter with suitable ac current range, and ac and dc voltage ranges of 0 – 440V and 0 – 250V respectively Continuity tester (if not included in the multimeter) Optical power meter with sensitivity 0 to –50dBm (to measure the optical signal level)
  • Page 359 P74x/EN CM/Na7 Commissioning (CM) 10-6 MiCOM P741, P742, P743 PRODUCT CHECKS These product checks cover all aspects of the relay which should be checked to ensure that it has not been physically damaged prior to commissioning, is functioning correctly and all input quantity measurements are within the stated tolerances.
  • Page 360 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-7 4.1.1 Visual inspection Carefully examine the relay to see that no physical damage has occurred since installation. The rating information given under the top access cover on the front of the relay should be checked to ensure it is correct for the particular installation.
  • Page 361 P74x/EN CM/Na7 Commissioning (CM) 10-8 MiCOM P741, P742, P743 FIGURE 2: REAR TERMINAL BLOCKS ON P743 The heavy duty terminal block is fastened to the rear panel using four crosshead screws. These are located top and bottom between the first and second, and third and fourth, columns of terminals (see Figure 3).
  • Page 362 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-9 P0299ENa FIGURE 3: LOCATION OF SECURING SCREWS FOR HEAVY DUTY TERMINAL BLOCKS. 4.1.3 Insulation Insulation resistance tests are only necessary during commissioning if it is required for them to be done and they have not been performed during installation.
  • Page 363 P74x/EN CM/Na7 Commissioning (CM) 10-10 MiCOM P741, P742, P743 If a P991 test block is provided the connections should be checked against the scheme (wiring) diagram. It is recommended that the supply connections are to the live side of the test block [coloured orange with the odd numbered terminals (1, 3, 5, 7 etc.).
  • Page 364 4.2.2.1 With an IRIG-B signal for Central Unit (P741) only If a satellite time clock signal conforming to IRIG-B is provided and the P741 relay has the optional IRIG-B port fitted, the satellite clock equipment should be energised. To allow the relay’s time and date to be maintained from an external IRIG-B source cell [DATE and TIME, IRIG-B Sync] must be set to ‘Enabled’.
  • Page 365 The alarm and out of service LED’s can be tested using the COMMISSION TESTS menu column. Set cell [COMMISSION TESTS, Test Mode] to ’Out Of Service’ on the P741 then select at least one zone or ‘50BF Disabled’ on the P742 / P743. Check that the out of service LED illuminates continuously and the alarm LED flashes.
  • Page 366 LED will operate during the setting checks performed later. Therefore, no further testing of the trip LED is required at this stage. Please note that the CB control function does not exist in the Central Unit (P741) as only the Peripheral Unit (P742/P743) may trip/close the local circuit breakers.
  • Page 367 Input opto-isolators This test checks that all the opto-isolated inputs on the relay are functioning correctly. The P741 relay has 8 opto-isolated inputs while the P742 relay has 16 opto-isolated inputs and P743 relays has 24 opto-isolated inputs. The opto-isolated inputs should be energised one at a time, see the external connection diagrams for the terminal numbers.
  • Page 368 Repeat the test for relays 2 to 8 for P741 and P742 relays, 2 to 16 for P743 relay. Return the relay to service by setting cell [COMMISSION TESTS, Test Mode] to ‘Disabled’.
  • Page 369 P74x/EN CM/Na7 Commissioning (CM) 10-16 MiCOM P741, P742, P743 Setting changes (e.g. of protection settings) are not supported in the current IEC 61850 implementation. To keep this process as simple as possible, such setting changes are done using S1 Agile Settings & Records program. This can be done as previously using the front port serial connection of the relay, or over the Ethernet link if preferred (this is known as “tunneling”).
  • Page 370 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-17 Check that communications can be established with this relay using the portable PC. 4.2.8.3 EIA(RS)232 configuration Connect a portable PC running the appropriate software (e.g. S1) to the rear EIA(RS)2321 port of the relay.
  • Page 371 P74x/EN CM/Na7 Commissioning (CM) 10-18 MiCOM P741, P742, P743 Providing all connections are correct and the software is working correctly, observe that the [1552 Loopback Status] cell that is located within the INTERMICOM COMMS displays “OK”. Set [1540 Ch Diagnostics] within INTERMICOM COMMS to “Visible”.
  • Page 372 P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-19 4.2.9 Current differential communications This test verifies that the P742 or P743 relay’s fibre optic communications ports used for communications to the P741 Central Unit, are operating correctly. IRIG-B12x WindRiver xWorks 20148098 LINK...
  • Page 373 P74x/EN CM/Na7 Commissioning (CM) 10-20 MiCOM P741, P742, P743 The measurement accuracy of the relay is ±5%. However, an additional allowance must be made for the accuracy of the test equipment being used. Corresponding CT Ratio Cell in MEASUREMENTS 1 column (02) (in ‘CT and VT RATIOS’...
  • Page 374 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-21 COMMISSIONING TEST MENU Test mode 5.1.1 Test mode for PU This cell is used to allow secondary injection testing to be performed on the relay, without operation of the trip relays, or commissioning of other relays in the same bay as the PU, without mal-operation of the breaker failure protection.
  • Page 375 P74x/EN CM/Na7 Commissioning (CM) 10-22 MiCOM P741, P742, P743 Busbar Monitoring (only in CU) The ‘BB monitoring’ cell is used to select the status of each zone. This cell has a binary string with one bit per zone which can be set to ‘1’ to disable busbar protection and ‘0’ to keep the zone in operating mode.
  • Page 376 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-23 SETTING CHECKS The setting checks ensure that all of the application-specific relay settings (i.e. both the relay’s function and programmable scheme logic settings), for the particular installation, have been correctly applied to the relay.
  • Page 377 P74x/EN CM/Na7 Commissioning (CM) 10-24 MiCOM P741, P742, P743 How to measure the Burden Resistance (R Insertion of the test block to open current circuit Short-circuit of the secondary P992 or MMLG winding of the current transformer (HV site) P3747ENc...
  • Page 378 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-25 6.2.1 / RB is close to 1 Insertion of the test block to open current circuit Short-circuit of the secondary P992 or MMLG winding of the current transformer (HV site) P3747ENc...
  • Page 379 P74x/EN CM/Na7 Commissioning (CM) 10-26 MiCOM P741, P742, P743 6.2.2 / RB is close to 3 P3901ENa = RAN / 2 = RBN / 2 = RCN / 2 = (RB + RB + RB ) / 9 The highest of the 3 phase values must be multiplied by 1.25 (25% increase at a 75°C temperature) and set in cell [CT/TT Ratios, RB in ohms].
  • Page 380 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-27 Fail & I<] are all set to “Disabled”. Make a note of which elements need to be re-enabled after testing. 6.3.1.1 Connect the test circuit The following tests require an injection test set, able to feed the relays with one or two currents variable in phase and magnitude.
  • Page 381 P74x/EN CM/Na7 Commissioning (CM) 10-28 MiCOM P741, P742, P743 When we reach the point A the Central Unit LED 8 and relay 8 will operate and when we reach the point B the differential element will operate. Note 1: >1 alarm timer will be set to 100s during the test.
  • Page 382 If not, monitor option will need to be used – see the next paragraph. On P741 go Central Unit GROUP1-->BUSBAR PROTECT and set I >1 Alarm timer to 100s On P742/3 go to COMMISSION TESTS column in the menu, scroll down and change cells [Monitor Bit 1] to [BUSBAR_TRIPPING].
  • Page 383 P74x/EN CM/Na7 Commissioning (CM) 10-30 MiCOM P741, P742, P743 6.3.2 Phase Overcurrent Protection (P742 and P743) If the overcurrent protection function is being used, both Ι>1 and I>2 elements should be tested. To avoid spurious operation of any current differential, earth fault, breaker fail or CT supervision elements, these should be disabled for the duration of the overcurrent tests.
  • Page 384 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-31 For all characteristics, allowance must be made for the accuracy of the test equipment being used. Operating time at twice current setting and time multiplier/time dial setting of 1.0 Characteristic Nominal (seconds) Range (seconds) [: Ι>1 Time Delay] setting...
  • Page 385 P74x/EN CM/Na7 Commissioning (CM) 10-32 MiCOM P741, P742, P743 6.3.3.2 External initiation of BF Protection Trip Command Trip A, B, C P742/3 Peripheral Unit P3752ENa FIGURE 10: EXTERNAL INITIATION OF BF PROTECTION To test the retrip: As shown in the Figure 10, we initiate the opto inputs “External Trip A,B,C” and apply a current twice the I<...
  • Page 386 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-33 CB unavailable: Zone 1 Zone 2 P3753ENa FIGURE 11: CB UNAVAILABLE Apply an internal fault in zone 2 and energise the opto input of PU3 “CB unavailable” and check that both bus-section 1 tripped simultaneously.
  • Page 387 P74x/EN CM/Na7 Commissioning (CM) 10-34 MiCOM P741, P742, P743 Check that the CU issued a trip command to both bus-sections (PU1, PU2 PU4 and PU5 should have operated). Important: The time indicated on the CU LCD is the duration of the operation of the CU trip order + 250ms (time of the PU to CU minimum duration signal information).
  • Page 388 MiCOM P741, P742, P743 (CM) 10-35 END TO END TESTS Verify communications between Peripheral units (P742 or P743) and Central Unit (P741) - Advisable for distributed scheme. The following communication checks confirm that the optical power at the transmit and receive ports of the Peripheral Units and the Central Unit are within the recommended operating limits.
  • Page 389 P74x/EN CM/Na7 Commissioning (CM) 10-36 MiCOM P741, P742, P743 ON-LOAD CHECKS The objectives of the on-load checks are to: − confirm the external wiring to the current inputs is correct. − ensure the on-load differential current is well below the relay setting.
  • Page 390 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-37 FINAL CHECKS The tests are now complete. Remove all test or temporary shorting leads, etc. If it has been necessary to disconnect any of the external wiring from the relay in order to perform the wiring verification tests, it should be ensured that all connections are replaced in accordance with the relevant external connection or scheme diagram.
  • Page 391 P74x/EN CM/Na7 Commissioning (CM) 10-38 MiCOM P741, P742, P743 COMMISSIONING TEST RECORD 10.1 Peripheral Units: P742/P743 Date: Engineer: Station: Circuit: System Frequency: Front Plate Information Peripheral Unit Type P74_ Model number Serial number Rated current In Auxiliary voltage Vx Test Equipment Used...
  • Page 392 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-39 Delete as appropriate Have all relevant safety instructions been Yes / No followed? Product Checks With the relay de-energised 4.1.1 Visual inspection Relay damaged? Yes / No Rating information correct for installation?
  • Page 393 P74x/EN CM/Na7 Commissioning (CM) 10-40 MiCOM P741, P742, P743 4.2.3.2 Trip (red) LED working? Yes / No 4.2.3.3 All 8 programmable LED’s working? Yes / No 4.2.4 Field supply voltage Value measured between terminals _______________V dc E7 and E9 (P742) or G7 and G9 (P743)
  • Page 394 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-41 4.2.6 Output relays: Complete or delete as appropriate (na = Not Applicable, nm = Not Measured) Relay 1 Working? Yes/No Contact resistance __________Ω / nm Relay 2 Working? Yes / No Contact resistance __________Ω...
  • Page 395 P74x/EN CM/Na7 Commissioning (CM) 10-42 MiCOM P741, P742, P743 4.2.6 Output relays: Complete or delete as appropriate (na = Not Applicable, nm = Not Measured) Relay 16 Working? Yes / No / na Contact resistance (N/O) __________Ω / nm (N/C) __________Ω...
  • Page 396 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-43 Setting Checks Complete or delete as appropriate Application-specific function settings applied? Yes / No Application-specific programmable scheme logic Yes / No / na settings applied (na = not applicable)? 5.2.1.2 Current Differential lower slope pickup ________________A 5.2.1.3...
  • Page 397 P74x/EN CM/Na7 Commissioning (CM) 10-44 MiCOM P741, P742, P743 EIA(RS)232 InterMiCOM Complete or delete as appropriate Not for What was loopback mode setting? P742 Amber alarm LED illuminated? Did ‘IM loopback’ appear on LCD? Did ‘loopback status’ indicate ‘OK’? Did any other unexpected alarm appear? Enter applied test pattern’...
  • Page 398 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-45 On-load Checks Delete as appropriate (na = not applicable) Test wiring removed? Yes / No / na Disturbed customer wiring re-checked? Yes / No / na Confirm current transformer wiring Complete or delete as appropriate (na = not applicable) 7.1.2...
  • Page 399 P74x/EN CM/Na7 Commissioning (CM) 10-46 MiCOM P741, P742, P743 SETTING RECORD 11.1 Central Unit: P741 Date: Engineer: Station: Circuit: System Frequency: Front Plate Information Central Unit type: P741 Model Number Serial Number Rated Current In Auxiliary Voltage Vx Setting Groups Used ...
  • Page 400 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-47 0000 SYSTEM DATA Alarm Status 2 Alarm Status 3 Access Level Password Control Password Level 1 Password Level 2 0600 PU CONF & STATUS PU in service PU Connected PU Topo valid...
  • Page 401 P74x/EN CM/Na7 Commissioning (CM) 10-48 MiCOM P741, P742, P743   Direct Access Enabled Disabled   Hotkey only CB Cntrl. only   Function Key Invisible Visible   InterMiCOM Disabled Enabled   RP1 Read Only Disabled Enabled ...
  • Page 402 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-49 0C00 DISTURB RECORDER Digital Input 20 Digital Input 21 Digital Input 22 Digital Input 23 Digital Input 24 Digital Input 25 Digital Input 26 Digital Input 27 Digital Input 28 Digital Input 29...
  • Page 403 P74x/EN CM/Na7 Commissioning (CM) 10-50 MiCOM P741, P742, P743 0E00 COMMUNICATIONS Ethernet NIC Protocol ________________ NIC MAC Address ________________ NIC Tunl Timeout ________________    NIC Link Report Alarm Event None NIC Link Timeout ________________s rear port RP2 Protocol ...
  • Page 404 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-51 1300 CONTROL I/P CONFIG Hotkey enabled _______________________________________ Control input Control command Enabled/ Latched Pulsed Set/Reset In/Out On/Off Disabled       Control input 1    ...
  • Page 405 P74x/EN CM/Na7 Commissioning (CM) 10-52 MiCOM P741, P742, P743 1500 INTERMICOM COMM IM Input Status ______________ IM Output Status ______________ Source address ______________ Receive address ______________ Baud rate ______________   Ch Statistics Invisible Visible Rx Direct count ______________ Rx Perm Count...
  • Page 406 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-53 1600 INTERMICOM CONF IM Msg Alarm Lvl ______________% Fallback Default Cmd Type mode value FrameSyncTim NA = Not applicable           ______ ms / ...
  • Page 407 P74x/EN CM/Na7 Commissioning (CM) 10-54 MiCOM P741, P742, P743 2900 CTRL I/P LABELS  _______________________ / Control input 1 Control input 1  _______________________ / Control input 2 Control input 2  _______________________ / Control input 3 Control input 3 ...
  • Page 408 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-55 2900 CTRL I/P LABELS  _______________________ / Control input 32 Control input 32  Control input 1 _______________________ / Control input 1  Control input 2 _______________________ / Control input 2 ...
  • Page 409 P74x/EN CM/Na7 Commissioning (CM) 10-56 MiCOM P741, P742, P743 11.1.4 Protection settings GROUP 1 PROTECTION SETTINGS For Group 2, 3 or 4 the first address figure must be respectively: “5 and 6”, “7and 8” or “9 and A” 3000 DIFF BUSBAR PROT...
  • Page 410 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-57 3100 BUSBAR OPTION Group 1 Group 2 Group 3 Group 4 Settings Settings Settings Settings CZ Circ Fault Mode [ ______ ] [ ______ ] [ ______ ] [ ______ ] with: [1] = No Block &...
  • Page 411 P74x/EN CM/Na7 Commissioning (CM) 10-58 MiCOM P741, P742, P743 4A00 INPUT LABELS Group 1 Group 2 Group 3 Group 4 Default = “Opto Label xx” Settings Settings Settings Settings Opto Input 7 _________ _________ _________ _________    ...
  • Page 412 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-59 11.2 Peripheral Units: P742/P743 Date: Engineer: Station: Circuit: System Frequency: Front Plate Information   Peripheral Unit type: P742 P743 Model Number Serial Number Rated Current In Auxiliary Voltage Vx Setting Groups Used ...
  • Page 413 P74x/EN CM/Na7 Commissioning (CM) 10-60 MiCOM P741, P742, P743 0000 SYSTEM DATA Alarm Status 2 Alarm Status 3 Access Level Password Control Password Level 1 Password Level 2 0800 DATE AND TIME   IRIG-B Sync Disabled Enabled  ...
  • Page 414 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-61 0900 CONFIGURATION   RP1 Read Only Disabled Enabled   RP2 Read Only Disabled Enabled   NIC Read Only Disabled Enabled LCD Contrast ____________________ 11.2.2 Disturbance recorder settings 0C00...
  • Page 415 P74x/EN CM/Na7 Commissioning (CM) 10-62 MiCOM P741, P742, P743 0C00 DISTURB RECORDER Digital Input 14    Input 14 Trigger No trigger Trigger L/H Trigger H/L Digital Input 15    Input 15 Trigger No trigger Trigger L/H...
  • Page 416 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-63 11.2.3 Control and support settings 0700 CB CONTROL Prot Trip Pulse ________________s   Trip Latched Disabled Enabled   If visible Reset Trip Latch CB Control By [ ________________ ]...
  • Page 417 P74x/EN CM/Na7 Commissioning (CM) 10-64 MiCOM P741, P742, P743 0D00 MEASURE’T SETUP Default Display   Local Values Primary secondary   Remote Values Primary secondary   Remote2 Values Primary secondary 0E00 COMMUNICATIONS RP1 Protocol RP1 Address ________________ RP1 InactivTimer ________________min ...
  • Page 418 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-65 1100 OPTOS CONFIG Global Nominal V _______ / _______V Opto Input 1 _______ / _______V Opto Input 2 _______ / _______V Opto Input 3 _______ / _______V Opto Input 4 _______ / _______V...
  • Page 419 P74x/EN CM/Na7 Commissioning (CM) 10-66 MiCOM P741, P742, P743 1300 CONTROL I/P CONFIG Hotkey enabled _______________________________________ Control input Control command Enabled/ Latched Pulsed Set/Reset In/Out On/Off Disabled       Control input 1    ...
  • Page 420 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-67 1500 INTERMICOM COMM (P743 only) IM Input Status ______________ IM Output Status ______________ Source address ______________ Receive address ______________ Baud rate ______________   Ch Statistics Invisible Visible Rx Direct count...
  • Page 421 P74x/EN CM/Na7 Commissioning (CM) 10-68 MiCOM P741, P742, P743 1600 INTERMICOM CONF (P743 only) IM Msg Alarm Lvl ______________% Fallback Default Cmd Type mode value FrameSyncTim NA = Not applicable           ______ ms / ...
  • Page 422 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-69 2900 CTRL I/P LABELS  _______________________ / Control input 1 Control input 1  _______________________ / Control input 2 Control input 2  _______________________ / Control input 3 Control input 3 ...
  • Page 423 P74x/EN CM/Na7 Commissioning (CM) 10-70 MiCOM P741, P742, P743 11.2.4 Protection settings GROUP 1 PROTECTION SETTINGS For Group 2, 3 or 4 the first address figure must be respectively: “5 and 6”, “7and 8” or “9 and A” 3000 BB TRIP CONFIRM...
  • Page 424 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-71 3800 EARTH FAULT Group 1 Group 2 Group 3 Group 4 Settings Settings Settings Settings ΙN>1 Function [ ______ ] [ ______ ] [ ______ ] [ ______ ] with: [1] = Disabled, [2] = DT, [3] = IEC S Inverse, [4] = IEC V Inverse,...
  • Page 425 P74x/EN CM/Na7 Commissioning (CM) 10-72 MiCOM P741, P742, P743 4600 SUPERVISION Group 1 Group 2 Group 3 Group 4 Settings Settings Settings Settings Error Factor Kce ________ ________ ________ ________ Alarm delay Tce ________s ________s ________s ________s Ι0 sup. blocking...
  • Page 426 Commissioning P74x/EN CM/Na7 MiCOM P741, P742, P743 (CM) 10-73 4A00 INPUT LABELS Group 1 Group 2 Group 3 Group 4 Default = “Opto Label xx” Settings Settings Settings Settings Opto Input 18 _________ _________ _________ _________    ...
  • Page 427 P74x/EN CM/Na7 Commissioning (CM) 10-74 MiCOM P741, P742, P743 4B00 OUTPUT LABELS Group 1 Group 2 Group 3 Group 4 Default = “Relay Label xx” Settings Settings Settings Settings Relay 14 _________ _________ _________ _________     Default...
  • Page 428 Maintenance P74x/EN MT/Na7 MiCOM P741, P742, P743 MAINTENANCE Hardware Suffix: J and K Software Version:...
  • Page 429 P74x/EN MT/Na7 Maintenance MiCOM P741, P742, P743...
  • Page 430 Maintenance P74x/EN MT/Na7 MiCOM P741, P742, P743 (MT) 11-1 CONTENTS MAINTENANCE Maintenance period Maintenance checks 1.2.1 Alarms 1.2.2 Opto-isolators 1.2.3 Output relays 1.2.4 Measurement accuracy Method of repair 1.3.1 Replacing the complete relay 1.3.2 Replacing a PCB Recalibration 1.4.1 P74x relay Changing the relay battery 1.5.1...
  • Page 431 P74x/EN MT/Ma7 Maintenance (MT) 11-2 MiCOM P741, P742, P743...
  • Page 432 GE protective relays are designed for a life in excess of 20 years. P74x current differential relays are self-supervising and so require less maintenance than earlier designs of relay.
  • Page 433 P74x/EN MT/Ma7 Maintenance (MT) 11-4 MiCOM P741, P742, P743 Method of repair P741, P742, P743 relays If the relay should develop a fault whilst in service, depending on the nature of the fault, the watchdog contacts will change state and an alarm condition will be flagged. Due to the extensive use of surface-mount components faulty PCBs should be replaced as it is not possible to perform repairs on damaged circuits.
  • Page 434 Maintenance P74x/EN MT/Na7 MiCOM P741, P742, P743 (MT) 11-5 FIGURE 1: LOCATION OF SECURING SCREWS FOR TERMINAL BLOCK Note: The use of a magnetic bladed screwdriver is recommended to minimise the risk of the screws being left in the terminal block or lost Without exerting excessive force or damaging the scheme wiring, pull the terminal blocks away from their internal connectors.
  • Page 435 The PCBs within the relay are now accessible. Figures 8, 9 and 10 show the PCB locations for the Central Unit (P741) in a size 80 TE case, and for Peripheral Units either in a size 40 TE case (P742) or in a size 60 TE case (P743).
  • Page 436 Assy Redundant Ethernet (RSTP) non Modulated IRIG-B ZN0071 006 Assy Redundant Ethernet (DHS) Modulated IRIG-B ZN0071 007 Assy Redundant Ethernet (DHS) non Modulated IRIG-B ZN0071 008 Assy Coprocessor 2070273 003 Assy Comms for Peripheral Units 2070273 001 FIGURE 2: P741 – PCB/MODULE LOCATIONS (VIEWED FROM FRONT)
  • Page 437 P74x/EN MT/Ma7 Maintenance (MT) 11-8 MiCOM P741, P742, P743 DESCRIPTION REFERENCE Assy Power Supply (24/54V) ZN0021 001 (48/125V) ZN0021 002 (110/250V) ZN0021 003 Assy Relay Output ZN0019 001 Assy Opto Input ZN0017 012 Assy Coprocessor 2070273 003 Assy High break relay output...
  • Page 438 Maintenance P74x/EN MT/Na7 MiCOM P741, P742, P743 (MT) 11-9 DESCRIPTION MATERIAL Assy Power Supply (24/54V) ZN0021 001 (48/125V) ZN0021 002 (110/250V) ZN0021 003 Assy Relay Output ZN0019 001 Assy Opto Input ZN0017 012 AssyEthernet (100Mbps) only ZN0049 001 Assy 2...
  • Page 439 P74x/EN MT/Ma7 Maintenance (MT) 11-10 MiCOM P741, P742, P743 1.3.2.1 Replacement of the main processor board ESD precautions should be taken to avoid damage to the microprocessor based circuits. The main processor board is located in the front panel, not within the case as with all the other PCBs.
  • Page 440 (MT) 11-11 1.3.2.2 Replacement of the optional board in P741 (same for P743) To replace a faulty board, disconnect all connections at the rear of the relay. The board is secured in the case by two screws accessible from the rear of the relay, one at the top and another at the bottom, as shown in Figure 6.
  • Page 441 Maintenance (MT) 11-12 MiCOM P741, P742, P743 Before fitting the replacement PCB check that the number on the round label adjacent to the front edge of the PCB matches the slot number into which it will be fitted. If the slot number is missing or incorrect write the correct slot number on the label.
  • Page 442 Maintenance P74x/EN MT/Na7 MiCOM P741, P742, P743 (MT) 11-13 Before fitting the replacement module check that the number on the round label adjacent to the front edge of the PCB matches the slot number into which it will be fitted. If the slot number is missing or incorrect write the correct slot number on the label.
  • Page 443 P3011ENa FIGURE 9: TYPICAL POWER SUPPLY BOARD FOR P742 & P743 FIGURE 10: ADDITIVE POWER SUPPLY BOARD FOR P741 Slot the power supply module back into the relay case, ensuring that it is pushed fully back on to the rear terminal blocks.
  • Page 444 FIGURE 11: TYPICAL RELAY BOARD 1.3.2.6 Replacement of the opto input, high break and separate relay boards (P741, P742, & P743) To remove either, gently pull the faulty PCB forward and out of the case. If the relay board is being replaced, ensure the setting of the link (located above IDC connector) on the replacement relay board is the same as the one being replaced.
  • Page 445 P74x/EN MT/Ma7 Maintenance (MT) 11-16 MiCOM P741, P742, P743 The replacement PCB should be carefully slid into the appropriate slot, ensuring that it is pushed fully back on to the rear terminal blocks. Refit the front panel using the reverse procedure to that given in section. After refitting and closing the access covers on size 60TE/80TE cases, press at the location of the hinge-assistance T-pieces so that they click back into the front panel moulding.
  • Page 446 Maintenance P74x/EN MT/Na7 MiCOM P741, P742, P743 (MT) 11-17 1.3.2.7 Replacement of the Coprocessor board Before replacing a faulty Coprocessor board, disconnect fibre optic cable connections at the rear of the relay. The board is secured in the case by two screws accessible from the rear of the relay, one at the top and another at the bottom, as shown in Figure 14.
  • Page 447 P74x/EN MT/Ma7 Maintenance (MT) 11-18 MiCOM P741, P742, P743 1.3.2.8 Replacement of the Comms board Before replacing a faulty Comms board (Communication board between central and peripheral units), disconnect fibre optic cable connections at the rear of the relay. The board is secured in the case by two screws accessible from the rear of the relay, one at the top and another at the bottom, as shown in Figure 15.
  • Page 448 Maintenance P74x/EN MT/Na7 MiCOM P741, P742, P743 (MT) 11-19 Recalibration 1.4.1 P74x relay Recalibration is not required when a PCB is replaced unless it happens to be one of the boards in the input module, the replacement of either directly affects the calibration.
  • Page 449 P74x/EN MT/Ma7 Maintenance (MT) 11-20 MiCOM P741, P742, P743 Cleaning Before cleaning the equipment ensure that all ac and dc supplies, current transformer and voltage transformer connections are isolated to prevent any chance of an electric shock whilst cleaning. The equipment may be cleaned using a lint-free cloth dampened with clean water. The use of detergents, solvents or abrasive cleaners is not recommended as they may damage the relay’s surface and leave a conductive residue.
  • Page 450 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 TROUBLESHOOTING Hardware Suffix: J and K Software Version:...
  • Page 451 P74x/EN TS/Na7 Troubleshooting MiCOM P741, P742, P743...
  • Page 452 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-1 CONTENTS INTRODUCTION INITIAL PROBLEM IDENTIFICATION POWER UP ERRORS ERROR MESSAGE/CODE ON POWER-UP OUT OF SERVICE LED ILLUMINATED ON POWER UP ERROR CODE DURING OPERATION MAL-OPERATION OF THE RELAY DURING TESTING Failure of output contacts...
  • Page 453 P74x/EN TS/Na7 Troubleshooting (TS) 12-2 MiCOM P741, P742, P743...
  • Page 454 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-3 INTRODUCTION Before carrying out any work on the equipment, the user should be familiar with the contents of the safety section/safety guide Pxxx-SG-4LM-2 or later issue, the technical data section and the ratings on the equipment rating label.
  • Page 455 P74x/EN TS/Na7 Troubleshooting (TS) 12-4 MiCOM P741, P742, P743 INITIAL PROBLEM IDENTIFICATION Consult the table below to find the description that best matches the problem experienced, then consult the section referenced to perform a more detailed analysis of the problem.
  • Page 456 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-5 POWER UP ERRORS If the relay does not appear to power up then the following procedure can be used to determine whether the fault is in the external wiring, auxiliary fuse, power supply module of the relay or the relay front panel.
  • Page 457 Last 4 digits provide details on the Other error codes relate to problems within actual error. the main processor board hardware or software. It will be necessary to contact GE with details of the problem for a full analysis. Relay displays...
  • Page 458 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-7 Test Check Action Relay resets on completion of Error 0x0E080000, programmable scheme power up - record error code logic error due to excessive execution time. displayed If relay powers up successfully, check programmable logic for feedback paths.
  • Page 459 P74x/EN TS/Na7 Troubleshooting (TS) 12-8 MiCOM P741, P742, P743 OUT OF SERVICE LED ILLUMINATED ON POWER UP Test Check Action Using the relay menu confirm If the setting is Enabled then disable the test whether the Commission Test/Test mode and, verify that the Out of Service LED Mode setting is Enabled.
  • Page 460 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-9 ERROR CODE DURING OPERATION The relay performs continuous self-checking, if an error is detected then an error message will be displayed, a maintenance record will be logged and the relay will reset (after a 1.6 second delay).
  • Page 461 PSL. Table 5: Error Codes Other error codes relate to problems within the main processor board software. It will be necessary to contact GE with details of the problem for a full analysis. EXTENDED LIST: Decimal Hexa Code...
  • Page 462 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-11 Decimal Hexa Code Problem Verify or modify code 0x8220xxxx TASK PRO software error Contact Call Centre 0x8221xxxx TASK PRO software error Contact Call Centre 0x8222xxxx TASK PRO software error Contact Call Centre...
  • Page 463 P74x/EN TS/Na7 Troubleshooting (TS) 12-12 MiCOM P741, P742, P743 Decimal Hexa Code Problem Verify or modify code 0x8377xxxx TASK DIAL software error Contact Call Centre 0x8378xxxx See list of CU_INIT_MAJOR to PU_INIT_MAJOR 0x8379xxxx See list of CU_INIT_PERIPH to PU_INIT_PERIPH 0x837Axxxx...
  • Page 464 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-13 Decimal Hexa Code Problem Verify or modify code 0x8530xxxx TASK SUP software error Contact Call Centre 0x8531xxxx TASK SUP software error Contact Call Centre 0x8532xxxx TASK SUP software error Contact Call Centre...
  • Page 465 P74x/EN TS/Na7 Troubleshooting (TS) 12-14 MiCOM P741, P742, P743 Decimal Hexa Code Problem Verify or modify code 0085 Coprocessor to Comm. board 6 Coprocessor or Comm. board 6 communication 0086 Coprocessor to Comm. board 6 Coprocessor or Comm. board 6...
  • Page 466 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-15 Decimal Hexa Code Problem Verify or modify code 0805 Coprocessor to Comm. board 2 Coprocessor or Comm. board 2 communication 0806 Coprocessor to Comm. board 2 Coprocessor or Comm. board 2...
  • Page 467 P74x/EN TS/Na7 Troubleshooting (TS) 12-16 MiCOM P741, P742, P743 Decimal Hexa Code Problem Verify or modify code 8001 Main to Coprocessor Coprocessor or Main board communication 8002 Main to Coprocessor Coprocessor or Main board communication 8003 Main to Coprocessor Coprocessor or Main board...
  • Page 468 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-17 Decimal Hexa Code Problem Verify or modify code 0207 Coprocessor to Comm. board 4 Coprocessor or Comm. board 4 or communication - no IT Comm. board 4 address 0401 Coprocessor to Comm. board 3 Coprocessor or Comm.
  • Page 469 P74x/EN TS/Na7 Troubleshooting (TS) 12-18 MiCOM P741, P742, P743 Decimal Hexa Code Problem Verify or modify code 2007 Coprocessor to Comm. board 0 Coprocessor or Comm. board 0 or communication - no IT Comm. board 0 address 3FC0 no IT Comm. board to Coprocessor...
  • Page 470 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-19 Decimal Hexa Code Problem Verify or modify code Logical OR See lines included in the logical OR See lines included Ex: 5010 = 4010 OR 1010 P742 / P743 - OPERATING MODE...
  • Page 471 P74x/EN TS/Na7 Troubleshooting (TS) 12-20 MiCOM P741, P742, P743 MAL-OPERATION OF THE RELAY DURING TESTING Failure of output contacts An apparent failure of the relay output contacts may be caused by the relay configuration; the following tests should be performed to identify the real cause of the failure. Note that the relay self-tests verify that the coil of the contact has been energized, an error will be displayed if there is a fault in the output relay board.
  • Page 472 Troubleshooting P74x/EN TS/Na7 MiCOM P741, P742, P743 (TS) 12-21 Incorrect analog signals (P742 or P743) The measurements may be configured in primary or secondary to assist. If it is suspected that the analog quantities being measured by the relay are not correct then the measurement function of the relay can be used to verify the nature of the problem.
  • Page 473 P74x/EN TS/Na7 Troubleshooting (TS) 12-22 MiCOM P741, P742, P743 REPAIR AND MODIFICATION PROCEDURE Please follow these 5 steps to return an Automation product to us: 1. Get the Repair and Modification Authorization Form (RMA)  To obtain a copy of the RMA form, please follow the link below: http://www.gegridsolutions.com/contact...
  • Page 474 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 SCADA COMMUNICATIONS Hardware Suffix: J and K Software Version:...
  • Page 475 P74x/EN SC/Na7 SCADA Communications MiCOM P741, P742, P743...
  • Page 476 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-1 CONTENTS SCADA COMMUNICATIONS Introduction 1.1.1 Read only mode (Command Blocking) Rear port information and connection advice – EIA(RS)485 protocols 1.2.1 Rear communication port EIA(RS)485 interface 1.2.2 Courier communication 1.2.3 MODBUS communication (not available) 1.2.4...
  • Page 477 FIGURE 3: UP TO 8 ADDRESSES EXAMPLE FIGURE 4: MORE THAN 8 ADDRESSES EXAMPLE FIGURE 5: SECOND REAR PORT EIA(RS)232 EXAMPLE FIGURE 6: ETHERNET CONNEXION EXAMPLE FIGURE 7: ETHERNET CONNEXION TO THE P741 ONLY FIGURE 8: ETHERNET CONNEXION TO THE P741 AND P743...
  • Page 478 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-3 SCADA COMMUNICATIONS Introduction This section outlines the remote communications interfaces of the relay. The relay supports a choice of one of five protocols via the Rear Port 1 communication interface, selected via the model number when ordering.
  • Page 479 P74x/EN SC/Na7 SCADA Communications (SC) 13-4 MiCOM P741, P742, P743 Allowed: Poll Class 1 (read spontaneous events) Poll Class 2 (read measurands) General Interrogation (GI) sequence Transmission of Disturbance Records sequence Time Synchronisation (ASDU6) INF23 activate characteristic 1 (ASDU20) INF24 activate characteristic 2 (ASDU20)
  • Page 480 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-5 1.2.1.3 Bus connections & topologies The EIA(RS)485 standard requires that each device be directly connected to the physical cable that is the communications bus. Stubs and tees are expressly forbidden, as are star topologies.
  • Page 481 • As the field voltage is much higher than that required, GE cannot assume responsibility for any damage that may occur to a device connected to the network as a result incorrect application of this voltage.
  • Page 482 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-7 P0109ENe FIGURE 2: REMOTE COMMUNICATION CONNECTION ARRANGEMENTS Having made the physical connection to the relay, the relay’s communication settings must be configured. To do this use the keypad and LCD user interface. In the relay menu firstly check that the ‘Comms.
  • Page 483 Default value of remote address is 255 and must be changed to 6 for the P741 or a value in the range of 7 to 34 for the P742 and P743. The next cell down controls the inactivity timer: Inactivity timer 10.00 min.
  • Page 484 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-9 CU Informations: Idiff & Ibias / Inputs / Outputs / Events / Disturbance records Central Unit MiCOM P741 K-BUS/Courier Peripheral Units MiCOM P743 & MiCOM P742 IEC60870-5-103 Optical fibre EIA(RS)485 / EIA(RS)232...
  • Page 485 P74x/EN SC/Na7 SCADA Communications (SC) 13-10 MiCOM P741, P742, P743 1.2.5 DNP3.0 communication (not available) The DNP 3.0 protocol is defined and administered by the DNP User Group. Information about the user group, DNP 3.0 in general and protocol specifications can be found on their website: www.dnp.org...
  • Page 486 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-11 The next cell down controls the inactivity timer. RP2 inactivity timer 15 mins. The inactivity timer controls how long the relay will wait without receiving any messages on the rear port before it reverts to its default state, including revoking any password access that was enabled.
  • Page 487 One I4XS4UE can connect up to 29 adresses (full P740 scheme) FIGURE 6: ETHERNET CONNEXION EXAMPLE 1.4.2 IEC 61850-8.1 protocol P741: Idiff (A,B,C) + Ibias (A,B,C) + Inputs + Outputs + Events + Disturbance Records… P741 P741 settings & PSL with MiCOM S1 via tunnelling IEC 61850-8-1 Fibre/Copper...
  • Page 488 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-13 P741: Idiff (A,B,C) + Ibias (A,B,C) + Inputs + Outputs + Events + Disturbance Records… P741 settings & PSL with MiCOM S1 via tunnelling P741 IEC 61850-8-1 Fibre/Copper IEC 61850-8-1...
  • Page 489 P74x/EN SC/Na7 SCADA Communications (SC) 13-14 MiCOM P741, P742, P743 COURIER INTERFACE Courier protocol K-Bus is based on EIA(RS)485 voltage levels with HDLC FM0 encoded synchronous signalling and its own frame format. The K-Bus twisted pair connection is unpolarized, whereas the EIA(RS)485 and EIA(RS)232 interfaces are polarized.
  • Page 490 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-15 Control Commands Select Setting Group Change Device Address* Set Real Time Note: Commands indicated with a * are not supported via the front Courier port. Relay courier database The Courier database is a two dimensional structure with each cell in the database being referenced by a row and column address.
  • Page 491 P74x/EN SC/Na7 SCADA Communications (SC) 13-16 MiCOM P741, P742, P743 Event extraction Events can be extracted either automatically (rear port only) or manually (either Courier port). For automatic extraction all events are extracted in sequential order using the standard Courier event mechanism, this includes fault/maintenance data if appropriate. The manual approach allows the user to select events, faults, or maintenance data at random from the stored records.
  • Page 492 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-17 2.5.4 Manual event record extraction Column 01 of the database can be used for manual viewing of event, fault, and maintenance records. The contents of this column will depend on the nature of the record selected. It is possible to select events by event number and to directly select a fault record or maintenance record by number.
  • Page 493 The protection relays can integrate with the PACiS substation control systems, to complete GE's offer of a full IEC 61850 solution for the substation. The majority of Px3x and Px4x relay types can be supplied with Ethernet, in addition to traditional serial protocols. Relays which have already been delivered with UCA2.0 on Ethernet can be easily upgraded to IEC...
  • Page 494 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-19 P1445ENb Data model layers in IEC 61850 The levels of this hierarchy can be described as follows: − Physical Device – Identifies the actual IED within a system. Typically device’s name or IP address can be used (for example Feeder_1 or 10.0.0.2).
  • Page 495 P74x/EN SC/Na7 SCADA Communications (SC) 13-20 MiCOM P741, P742, P743 IEC 61850 in MiCOM relays IEC 61850 is implemented in relays by use of a separate Ethernet card. This card manages the majority of the IEC 61850 implementation and data transfer to avoid any impact on the performance of the protection.
  • Page 496 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-21 3.3.2.1 Configuration Banks To promote version management and minimize down-time during system upgrades and maintenance, the relays have incorporated a mechanism consisting of multiple configuration banks. These configuration banks are categorized as: •...
  • Page 497 P74x/EN SC/Na7 SCADA Communications (SC) 13-22 MiCOM P741, P742, P743 Peer-to-peer (GSE) communications The implementation of IEC 61850 Generic Substation Event (GSE) sets the way for cheaper and faster inter-relay communications. The generic substation event model provides the possibility for a fast and reliable system-wide distribution of input and output data values.
  • Page 498 SCADA Communications P74x/EN SC/Na7 MiCOM P741, P742, P743 (SC) 13-23 3.7.1 Ethernet disconnection IEC 61850 ‘associations’ are unique and made to the relay between the client (master) and server (IEC 61850 device). In the event that the Ethernet is disconnected, such associations are lost, and will need to be re-established by the client.
  • Page 499 P74x/EN SC/Na7 SCADA Communications (SC) 13-24 MiCOM P741, P742, P743...
  • Page 500 Symbols and Glossary P74x/EN SG/Na7 MiCOM P741, P742, P743 SYMBOLS AND GLOSSARY Hardware Suffix: J and K Software Version:...
  • Page 501 P74x/EN SG/Na7 Symbols and Glossary MiCOM P741, P742, P743...
  • Page 502 Symbols and Glossary P74x/EN SG/Na7 MiCOM P741, P742, P743 (SG) 14-1 Logic Symbols used Symbols Explanation & Logical “AND”: Used in logic diagrams to show an AND-gate function. Σ “Sigma”: Used to indicate a summation, such as cumulative current interrupted.
  • Page 503 Abbreviation of “Control”: As used for the Control Inputs function. Current transformer supervision: To detect CT input failure. Abbreviation of “Central Unit” (P741) Abbreviation of “Check Zone”: Zone taking into account only the feeders. Digital data bus within the programmable scheme logic: A logic point that has a zero or 1 status.
  • Page 504 Symbols and Glossary P74x/EN SG/Na7 MiCOM P741, P742, P743 (SG) 14-3 Symbols Explanation GRP. Abbreviation of “Group”: Typically an alternative setting group. Generic Substation Event: In IEC 61850, the generic substation event model provides the possibility for a fast and reliable system-wide distribution of input and output data values (peer-peer communication).
  • Page 505 P74x/EN SG/Na7 Symbols and Glossary (SG) 14-4 MiCOM P741, P742, P743 Symbols Explanation ID>2 Minimum pick-up differential phase element for all the zones. IDCZ>2 Minimum pick-up differential phase element for the Check Zone. IDMT Inverse definite minimum time: A characteristic whose trip time depends on the measured input (e.g. current) according to an inverse-time curve.
  • Page 506 Symbols and Glossary P74x/EN SG/Na7 MiCOM P741, P742, P743 (SG) 14-5 Symbols Explanation A “miniature circuit breaker”: Used instead of a fuse to protect VT secondary circuits. Model Implementation Conformance Specification: MICS Defines the IEC 61850 data model implemented in an IED.
  • Page 507 P74x/EN SG/Na7 Symbols and Glossary (SG) 14-6 MiCOM P741, P742, P743 Symbols Explanation A resistance. R Gnd. A distance zone resistive reach setting: Used for ground (earth) faults. Lead burden for the neutral. RBPh Lead burden for the phases. Abbreviation of “Relay Characteristic Angle”: The centre of the directional characteristic.
  • Page 508 Symbols and Glossary P74x/EN SG/Na7 MiCOM P741, P742, P743 (SG) 14-7 Symbols Explanation V<1 First stage of undervoltage protection: Could be labelled 27-1 in ANSI terminology. V<2 Second stage of undervoltage protection: Could be labelled 27-2 in ANSI terminology. V>...
  • Page 509 P74x/EN SG/Na7 Symbols and Glossary (SG) 14-8 MiCOM P741, P742, P743 Logic Timers Logic Explanation Time Chart Symbols Delay on pick-up timer, t Delay on drop-off timer, t Delay on pick-up/drop-off timer Pulse timer Pulse pick-up falling edge Pulse pick-up raising edge...
  • Page 510 Symbols and Glossary P74x/EN SG/Na7 MiCOM P741, P742, P743 (SG) 14-9 Logic Explanation Time Chart Symbols Dwell timer Straight (non latching): Hold value until input reset signal...
  • Page 511 P74x/EN SG/Na7 Symbols and Glossary (SG) 14-10 MiCOM P741, P742, P743 Logic Gates...
  • Page 512 Installation P74x/EN IN/Na7 MiCOM P741, P742, P743 INSTALLATION Hardware Suffix: J and K Software Version:...
  • Page 513 P74x/EN IN/Na7 Installation MiCOM P741, P742, P743...
  • Page 514 Installation P74x/EN IN/Na7 MiCOM P741, P742, P743 (IN) 15-1 CONTENTS RECEIPT OF RELAYS HANDLING OF ELECTRONIC EQUIPMENT STORAGE UNPACKING RELAY MOUNTING Rack mounting Panel mounting RELAY WIRING Medium and heavy duty terminal block connections RS485 port IRIG-B connections (P741 only)
  • Page 515 P74x/EN IN/Na7 Installation (IN) 15-2 MiCOM P741, P742, P743...
  • Page 516 Installation P74x/EN IN/Na7 MiCOM P741, P742, P743 (IN) 15-3 RECEIPT OF RELAYS Protective relays, although generally of robust construction, require careful treatment prior to installation on site. On receipt, relays should be examined immediately to ensure no external damage has been sustained in transit.
  • Page 517 P74x/EN IN/Na7 Installation (IN) 15-4 MiCOM P741, P742, P743 HANDLING OF ELECTRONIC EQUIPMENT A person’s normal movements can easily generate electrostatic potentials of several thousand volts. Discharge of these voltages into semiconductor devices when handling electronic circuits can cause serious damage which, although not always immediately apparent, will reduce the reliability of the circuit.
  • Page 518 Installation P74x/EN IN/Na7 MiCOM P741, P742, P743 (IN) 15-5 STORAGE If relays are not to be installed immediately on receipt, they should be stored in a place free from dust and moisture in their original cartons. Where de-humidifier bags have been included in the packing they should be retained.
  • Page 519 P74x/EN IN/Na7 Installation (IN) 15-6 MiCOM P741, P742, P743 UNPACKING Care must be taken when unpacking and installing the relays so that none of the parts are damaged and additional components are not accidentally left in the packing or lost.
  • Page 520 Installation P74x/EN IN/Na7 MiCOM P741, P742, P743 (IN) 15-7 RELAY MOUNTING The relays are dispatched either individually or as part of a panel/rack assembly. Individual relays are normally supplied with an outline diagram showing the dimensions for panel cut-outs and hole centres. This information can also be found in the product publication.
  • Page 521 P74x/EN IN/Na7 Installation (IN) 15-8 MiCOM P741, P742, P743 Rack mounting Relays may be rack mounted using single tier rack frames (our part number FX0121 001), as illustrated in Figure 2. These frames have been designed to have dimensions in accordance with IEC60297 and are supplied pre-assembled ready to use.
  • Page 522 Installation P74x/EN IN/Na7 MiCOM P741, P742, P743 (IN) 15-9 30TE GJ2128 006 35TE GJ2128 007 40TE GJ2128 008 TABLE 1: BLANKING PLATES Panel mounting The relays can be flush mounted into panels using M4 SEMS Taptite self-tapping screws with captive...
  • Page 523 P74x/EN IN/Na7 Installation (IN) 15-10 MiCOM P741, P742, P743 RELAY WIRING Before carrying out any work on the equipment, the user should be familiar with the contents of the safety section/safety guide Pxxx-SG-4LM-2 or later, the technical data section and the ratings on the equipment rating label.”...
  • Page 524 Installation P74x/EN IN/Na7 MiCOM P741, P742, P743 (IN) 15-11 IRIG-B connections (P741 only) The IRIG-B input and BNC connector have a characteristic impedance of 50Ω. It is recommended that connections between the IRIG-B equipment and the relay are made using coaxial cable of type RG59LSF with a halogen free, fire retardant sheath.
  • Page 525 P74x/EN IN/Na7 Installation (IN) 15-12 MiCOM P741, P742, P743 P741 - CENTRAL UNIT FIGURE 3: P741 (80TE) – HARDWARE DESCRIPTION...
  • Page 526 Installation P74x/EN IN/Na7 MiCOM P741, P742, P743 (IN) 15-13...
  • Page 527 P74x/EN IN/Na7 Installation (IN) 15-14 MiCOM P741, P742, P743 FIGURE 4: P741 (80TE) – REAR VIEW P742 – PERIPHERAL UNIT FIGURE 5: P742 (40TE) – HARDWARE DESCRIPTION...
  • Page 528 Installation P74x/EN IN/Na7 MiCOM P741, P742, P743 (IN) 15-15 FIGURE 6: P742 (40TE) – REAR VIEW...
  • Page 529 P74x/EN IN/Na7 Installation (IN) 15-16 MiCOM P741, P742, P743 P743 – PERIPHERAL UNIT FIGURE 7: P743 (60TE) – HARDWARE DESCRIPTION...
  • Page 530 Installation P74x/EN IN/Na7 MiCOM P741, P742, P743 (IN) 15-17 FIGURE 8: P743 (60TE) – REAR VIEW...
  • Page 531 P74x/EN IN/Na7 Installation (IN) 15-18 MiCOM P741, P742, P743 EXTERNAL CONNECTION DIAGRAMS Please refer to Appendix A to see the full list of wiring and communication diagrams.
  • Page 532 Firmware and Service Manual P74x/EN VH/Na7 Version History MiCOM P741, P742, P743 FIRMWARE AND SERVICE MANUAL VERSION HISTORY Hardware Suffix: J and K Software Version:...
  • Page 533 P74x/EN VH/Na7 Firmware and Service Manual Version History MiCOM P741, P742, P743...
  • Page 534  Original Issue Feb 2003 V2.07 P740/EN xx/D22  First release to production  Original Issue  P741 and P743 Evolution with extended User Interface (32 Controls Inputs, 10 Function Keys and 18 tricolour LEDs). V2.12 C3.4 J or K May 2006 P740/EN xx/E33 ...
  • Page 535 Suffix Date of Issue Compatibility Documentation Major Minor  Spurious error codes does not appear any more during power up of the P741  The Ethernet board and the Coprocessor board are compatible V2.13 C3.7 J or K Jan 2007 P740/EN xx/F44 ...
  • Page 536 Relay type: P740 … Software Hardware Original Technical Version Description of Changes Suffix Date of Issue Compatibility Documentation Major Minor  The status of the trip relays 1, 2, 3 is stored in BBRAM even if the “Trip Latched” function is disabled in the column “CB Control”...
  • Page 537  Initial software release with: the second rear port & interrupt V2.14 D3.1 J or K February 2008 driven interMiCOM for the P741 and P743 and PSL P740/EN xx/I76 Patch 41 Enhancement Positional Data and SR Latch Gates  Initial software release with the Addition of the Px40 Remote V2.14...
  • Page 538 Relay type: P740 … Software Hardware Original Technical Version Description of Changes Suffix Date of Issue Compatibility Documentation Major Minor E2.0 Jan 2010 Software (cont’d):  CB supervision time delay is settable.  I0 supervision with neutral current measured can block 87BB protection.
  • Page 539 Relay Software Version                               ...
  • Page 540 Relay Software Version               *: P742 & P743...
  • Page 541 Relay Software Version                               ...
  • Page 542 APPENDIX A WIRING DIAGRAMS...
  • Page 543 Appendix A - Wiring Diagrams P74x P74x/EN M/Na7...
  • Page 544 Model External Connection Diagram Title Drawing-Sheet Issue COMMS OPTIONS MICOM Px40 PLATFORM 10Px4001-1 P741 BUSBAR PROTECTION CENTRAL UNIT P741 (80TE) 10P74101-1 BUSBAR PROTECTION PERIPHERAL UNIT P742 (40TE) 10P74201-1 P742 BUSBAR PROTECTION PERIPHERAL UNIT P742 (40TE) 10P74202-1 BUSBAR PROTECTION PERIPHERAL UNIT P743 (60TE)
  • Page 560 Imagination at work Grid Solutions St Leonards Building Redhill Business Park Stafford, ST16 1WT, UK +44 (0) 1785 250 070 www.gegridsolutions.com/contact © 2017 General Electric. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied on that it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances.

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