Electro Industries/GaugeTech Nexus 1250 Installation & Operation Manual
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Electro Industries/GaugeTech Nexus 1250 Installation & Operation Manual

High performance scada monitor
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Nexus 1250
High Performance SCADA Monitor
Installation & Operation Manual
Revision 1.21
March 20, 2001
Doc #: E107-7-06-121
e
Electro Industries/GaugeTech
1800 Shames Drive
Westbury, New York 11590
Tel: 516-334-0870
Fax: 516-338-4741
u
Sales@electroind.com
www.electroind.com
u
"The World Leader in Power Monitoring Systems"
Courtesy of NationalSwitchgear.com

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  • Page 1 Nexus 1250 High Performance SCADA Monitor Installation & Operation Manual Revision 1.21 March 20, 2001 Doc #: E107-7-06-121 Electro Industries/GaugeTech 1800 Shames Drive Westbury, New York 11590 Tel: 516-334-0870 Fax: 516-338-4741 Sales@electroind.com www.electroind.com “The World Leader in Power Monitoring Systems”...
  • Page 2 Electro Industries/GaugeTech Doc # E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 3 Nexus 1250 Installation and Operation Manual Revision 1.21 Published by: Electro Industries/GaugeTech 1800 Shames Drive Westbury, NY 11590 All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical,...
  • Page 4 This warranty does not apply to defects resulting from unauthorized modification, misuse, or use for any reason other than electrical power monitoring. The Nexus 1250 is not a user-serviceable product. OUR PRODUCTS ARE NOT TO BE USED FOR PRIMARY OVER-CURRENT PROTECTION. ANY PROTECTION FEATURE IN OUR PRODUCTS IS TO BE USED FOR ALARM OR SECONDARY PROTECTION ONLY.
  • Page 5 Today, with the Nexus 1250, EIG is a leader in the development and production of power-monitoring products. All EIG products are designed, manufactured, tested and calibrated at our facility in Westbury, New York.
  • Page 6 Electro Industries/GaugeTech Doc # E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 7: Table Of Contents

    5.9: RS-485 Connectiion- Nexus Monitor to the Nexus P60N External Display ..5-12 5.10: Communication Ports on the Nexus I/O Modules ....5-13 Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 8 ....... 7-1 7.2: Nexus 1250 Transformer Loss Compensation ....7-2 7.3: Loss Compensation Percentages .
  • Page 9 11.2: Hardware Connection ......11-3 Glossary of Terms Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 10 Figure 5.12: Communication Ports on the Nexus I/O Modules ... . . 5-13 Figure 5.13: Nexus Monitor Connected to Nexus I/O Module ... . . 5-14 Electro Industries/GaugeTech viii Doc #: E107-7-06-121...
  • Page 11 Chapter 11: Nexus Monitor with Internal Network Option Figure 11.1: Nexus with Internal Network Option ....11-1 Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 12 Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 13: Chapter 1: Basic Tutorial On Ac Power Measurement

    This is a measure of the inefficiency of the electrical system. Apparent power (VA) is the total power delivered to the load, and the vector sum of real power and reactive power. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 14: Three-Phase Systems

    A typical three-phase configuration has either a Delta connection or a Wye connection. In a three phase system, the voltage levels between the phases and the neutral are uniform and defined by: Delta Figure 1.3: Three Phase Power Systems Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 15: Poly Phase Systems

    WH = W x T Consumption is typically measured in kilowatt-hours (kWh): one thousand watts consumed over one hour. Utilities use the WH equation to determine the overall consumption in a billing period. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 16: Waveform And Harmonics

    The Nexus 1250 monitors the harmonic distortion to the 83rd harmonic. A waveform capture of the distorted waveform can be read with the Nexus Communicator software.

  • Page 17: Chapter 2: Nexus Overview

    2.1: The Nexus System 2.1: The Nexus System Electro Industries’ Nexus 1250 combines high-end revenue metering with sophisticated power quality analysis. Its advanced monitoring capabilities provide detailed and precise pictures of any metered point within a distribution network. Extensive I/O capability is available in conjunction with all metering functions.
  • Page 18 Measures and records Harmonics to the 83rd order. • Offers inputs for neutral-to-ground voltage measurements. • Synchronizes with IRIG-B clock signal. Nexus 1250 Memory, Communication and Control: • Up to 4 Meg NVRAM. • 4 High Speed Communication Ports. •...

  • Page 19: Measurements And Calculations

    2.2: Measurements and Calculations 2.2: Measurements and Calculations The Nexus 1250 Monitor measures many different power parameters. The following is a list of the formulas used to conduct calculations. Root Mean Square (RMS) of Voltages: n = number of samples ∑...
  • Page 20 Reactive Power (VAR): − Watt Power (Watts): × sample samples Power Factor (PF): Watt Phase Angles: ∠ − Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 21 % Total Harmonic Distortion (%THD): f= fundamental; h = harmonic order ∑ × K Factor: h = harmonic order; pu = per unit rms current for each of the harmonic frequencies ∑ Factor Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 22: Demand Integrators

    Peak demand, expressed in kilowatts (kW), is the highest level of demand recorded during a set period of time, called the interval. The Nexus 1250 supports the following most popular conventions for averaging demand and peak demand: Thermal Demand, Fixed Window Demand, Sliding Window Demand and Predictive Window Demand.

  • Page 23: Nexus External I/O Modules (Optional)

    PSIO: Additional power supply for up to six I/O modules. This unit is necessary if you are connecting more than four I/O modules to a Nexus Monitor. • MBIO: Bracket for surface-mounting I/O modules to any enclosure. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 24: Nexus Monitor Specifications

    -40°C to +70°C / -40°F to +158°F Auxiliary Output Power Voltage 15–20 VDC at 50–200mA Maximum Auxiliary Power Current 1.6A (short protected) 1244* UL Listing *Not evaluated for accuracy, reliability or capability to perform intended function Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 25: Nexus P40N External Display Specifications

    Nominal Power Consumption Approximately 4.5 watts Operating Temperature Range 0°C to + 50°C / +32°F to +122°F Overall Dimensions (HxWxL) 1.6 x 5.4 x 8.0 in / 4.0 x 13.7 x 20.3 cm Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 26 Electro Industries/GaugeTech 2-10 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 27: Chapter 3: Hardware Installation

    Relative Humidity: 5 to 95% non-condensing 10.5” (26.67cm) 2 x 3.25” (8.25cm) 2x4.0” (10.16cm) 7.25” (18.41cm) 6.74” (17.11cm) 4 x 0.221” (5.61mm) Thru Slot (For #10 Screw) Figure 3.1: Nexus Monitor Mounting Diagram, Top View Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 28 Nexus Monitor Mounting Diagram, Side View 2.35” (5.96cm) 3.40” (8.63cm) (MAX) Figure 3.2 Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 29: Mounting The Nexus P40N External Display

    3.2: Mounting the Nexus P40N LED External Display 3.2: Mounting the Nexus P40N LED External Display The Nexus 1250 LED Display, Model # P40N, mounts using a standard ANSI C39.1 drill plan. Secure the four mounting studs to the back of the panel with the supplied nuts.

  • Page 30: Mounting The Nexus P60N Touch Screen External Display

    Figure 3.4: Nexus P60N Touch Screen Display Mounting Diagram The Nexus 1250 P60N Touch Screen Display mounts easily, using the diagrams above and on the next page. A bezel and a gasket are included with the P60N. Since the P60N employs an LCD display, the viewing angle must be considered when mounting.

  • Page 31: Figure 3.6: Cutout For Nexus P60N Touch Screen Display

    Carefully “drop in” the P60N with bezel and gasket attached. See Figure 3.7 below for details. Fasten the unit securely with the four 6-32 hex nuts supplied. Figure 3.7: Nexus P60N Touch Screen Display Bezel Mounting Diagram Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 32: Mounting The Nexus External I/O Modules

    4.215” (10.70cm) Mounting Bracket Figure 3.8: Nexus I/O Modules Mounting Diagram, Overhead View Mounting Brackets (MBIO) Female RS-485 Side Port I/O Port Male RS-485 Side Port Figure 3.9: Nexus I/O Module Communication Ports Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 33 Nexus I/O Modules Mounting Diagram, Front View Mounting Bracket (MBIO) Mounting Bracket (MBIO) 1.25” (3.17cm)+Y Per Module 2.20” (5.58cm) 3.41” (8.66cm) 2x1.10” (2.79cm) 0.605” (1.53cm) 1.235” (3.13cm) Figure 3.10 Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 34 Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 35: Chapter 4: Electrical Installation

    Mount the current transformers (CTs) as close as possible to the meter. The following table illustrates the maximum recommended distances for various CT sizes, assuming the connection is via 14 AWG cable. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 36: Isolating A Ct Connection Reversal

    L+ terminal and the negative (ground) supply wire to the N- terminal on the Nexus. Power supply options and corresponding suffixes are listed in the following table. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 37: Wiring Diagrams

    3-Wire, 2-Element Open Delta with 2 PTs and 2 CTs 3-Wire, 2-Element Delta Direct Voltage with 3 CTs 3-Phase, 4-Wire Wye, 2.5 Element with 2 PTs and 3 CTs 4-Wire, 3-Element Grounded Delta with 4 CTs Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 38: Figure 4.1: 4-Wire Wye, 3-Element Direct Voltage With 4 Cts

    0.25 A INPUT Figure 4.1: 4-Wire Wye, 3-Element Direct Voltage with 4 CTs Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 39: Figure 4.2: 4-Wire Wye, 3-Element With 3 Pts And 4 Cts

    0.25 A INPUT Figure 4.2: 4-Wire Wye, 3-Element with 3 PTs and 4 CTs Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 40: Figure 4.3: 3-Wire, 2-Element Open Delta With 2 Pts And 3 Cts

    0.25 A INPUT Figure 4.3: 3-Wire, 2-Element Open Delta with 2 PTs and 3 CTs Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 41 0.25 A INPUT Figure 4.4: 3-Wire, 2-Element Open Delta with 2 PTs and 2 CTs Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 42: Figure 4.5: 3-Wire, 2-Element Delta Direct Voltage With 3 Cts

    0.25 A INPUT Figure 4.5: 3-Wire, 2-Element Delta Direct Voltage with 3 CTs Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 43: Figure 4.6: 3-Phase, 4-Wire Wye, 2.5 Element With 2 Pts And 3 Cts

    0.25 A INPUT Figure 4.6: 3-Phase, 4-Wire Wye, 2.5 Element with 2 PTs and 3 CTs Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 44: Figure 4.7: 4-Wire, 3-Element Grounded Delta With 4 Cts

    0.25 A INPUT Note: To use this diagram, you must order a “G” Unit. Figure 4.7: 4-Wire, 3-Element Grounded Delta with 4 CTs Electro Industries/GaugeTech 4-10 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 45: Communication Overview

    RS-485 (daisy chain) MODEM RS-232 Nexus Null Modem Telephone Line, MODEM Fiber Optic Link or RS-232 RS-485 RS-232/485 Converter Radio Link Nexus (Modem Manager) Nexus Nexus Figure 5.1: Communication Overview Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 46: Figure 5.2: Rj-11 Communication With Internal Modem Option

    Gateway. If you are going to use RS-485 to connect multiple Nexus monitors, you MUST use the Modem Gateway. For more details, see Chapter 10 of this manual. RS-485 RJ-11 Daisy Chain Originate Modem (or Internal to PC) Figure 5.2: RJ-11 Communication with Internal Modem Option Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 47: Figure 5.3: Rj-45 Communication With Internal Network Option

    MUST use the Ethernet Gateway. For more details, see Chapter 11 of this manual. RS-485 MODBUS/RTU 10 BASE-T RJ-45 MODBUS/TCP over Ethernet Daisy Chain Network Figure 5.3: RJ-45 Communication with Internal Network Option Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 48: Figure 5.4: Communication Wiring

    Ports 1, 3 and 4 DO NOT change.The I/O Modules MUST use Port 4 (Port 3 is an alternate). The Nexus P40N Display is shipped programmed to use Port 3—see section 5.7 for details. Figure 5.4: Communication Wiring Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 49: Rs-232 Connection-Nexus Monitor To A Computer

    Two-wire, RS-485 communication terminals: Connect the A(+) terminal of the Nexus Port to the (+) terminal of the device. Connect the B(-) terminal of the Nexus Port to the (-) terminal of the device. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 50 (+) and (-) terminals of each device at the end of a straight-line bus. The line impedance of the cable and the resistor should match. Generally, a 100- or 120-Ohm resistor will work. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 51 Correct Connection RS-485 Connection R T= ~120 Ohms Twisted Pair R T= ~120 Ohms + V - B(-) A(+) Figure 5.7: 2-Wire RS-485 Connection Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 52: Figure 5.8: Incorrect "T" And "Star" Topologies

    Incorrect Connection: “Star” “Star” Connection Incorrect! The three wires connected in a “Star” shape on both the (+) and (-) terminals will cause interference problems. RS-485 Ports Figure 5.8: Incorrect “T” and “Star” Topologies Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 53: Rs-485 Connection- Nexus Monitor To A Computer Or Plc

    (which is labeled Ethernet Gateway) as a Master and an RS-485 connection. The link using RS-485 is capable for up to 4000 feet (1219 meters). For more information on the Nexus Monitor with the Internal Network Option, see Chapter 11 of this manual. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 54: Rs-485 Connection- Nexus To An Rs-485 Master (Unicom Or Modem Manager)

    – – + + G Port on RS-485 Master Port on Nexus Monitor + V - S B(-) A(+) Figure 5.9: Nexus Monitor Connected to an RS-485 Master Electro Industries/GaugeTech 5-10 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 55: Rs-485 Connectiion- Nexus Monitor To The Nexus P40N External Display

    A(+) B(-) S - V + Nexus P40N Display, Back View B(-) A(+) Bottom Nexus Monitor Port 3 + V - S B(-) A(+) Figure 5.10: Nexus Monitor Connected to Nexus P40N External Display Electro Industries/GaugeTech 5-11 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 56: Rs-485 Connectiion- Nexus Monitor To The Nexus P60N External Display

    5 DCIN (12-30VDC) 4 (GND) Black 3 (485+) A(+) White 2 (485-) B(-) Black 1 (GND) Silver Nexus Monitor Port 3 Figure 5.11: Nexus Monitor Connected to Nexus P60N Touch Screen Display Electro Industries/GaugeTech 5-12 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 57: Communication Ports On The Nexus I/O Modules

    For more detail, refer below to section 5.11 and to Chapter 9 of this manual. Mounting Brackets Female RS-485 Side Port LEDs I/O Port (Size and pin configuration vary) Male RS-485 Side Port Figure 5.12: Communication Ports on the Nexus I/O Modules Electro Industries/GaugeTech 5-13 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 58: Rs-485 Connection-Nexus Monitor To Nexus I/O Modules

    A(+) B(-) S - V + Male Side Port on Nexus I/O Module Nexus Monitor Port 4 + V - S B(-) A(+) Figure 5.13: Nexus Monitor Connected to Nexus I/O Module Electro Industries/GaugeTech 5-14 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 59: Steps To Determine Power Needed

    2.7 VA 8D11 8 Status Inputs (Wet/Dry) 1.0 VA 4RTD1 4 RTD Inputs 3.6 VA NEXUS DISPLAYS’ VA RATINGS P40N Nexus LED Display 8 VA P60N Nexus Touch Screen Display 5 VA Electro Industries/GaugeTech 5-15 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 60: Linking Multiple Nexus Devices In Series

    GND TX- RX- TX+ RX+ + V - S B(-) A(+) + V - S B(-) A(+) + V - S B(-) A(+) Jumpers Figure 5.14: Linking Multiple Nexus Devices in Series Electro Industries/GaugeTech 5-16 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 61: Networking Groups Of Nexus Monitors

    Maximum 31 Nexus Monitors, RS-485 Maximum 31 Repeaters REPEATER Nexus Nexus Nexus Nexus Nexus Maximum 31 Nexus Monitors, RS-485 REPEATER Nexus Nexus Nexus Nexus Nexus RS-485/232 Converter Figure 5.15: Networking Groups of Nexus Monitors Electro Industries/GaugeTech 5-17 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 62: Remote Communication Overview

    Use modems (dedicated or dial-up) when devices are at great distances. EIG recommends using RS-485 wiring with a Modem Manager. See section 5.13. Remote Connection—RS-232 PC at office Local PSTN (Public Remote Nexus 1250 Monitor Modem Switched Modem Telephone Network) RS-232...

  • Page 63: Figure 5.17: Remote Connections With Internal Modem Option

    Standard Telephone wall to phone cabling can be used. This cabling is widely available in many lengths with RJ-11 plugs on each end. Plug one end into the Nexus and the other end into the wall jack. Electro Industries/GaugeTech 5-19 Doc #: E107-7-06-121...

  • Page 64: Figure 5.18: Remote Connections With Internal Network Option

    Or, use RJ-45 Network Connection when devices are at great distances. Connections are simple, requiring no additional hardware. RS-485 MODBUS/RTU 10 BASE-T RJ-45 MODBUS/TCP over Ethernet Daisy Chain Network Figure 5.18: Remote Connections with Internal Network Option Electro Industries/GaugeTech 5-20 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 65: Remote Communication- Rs-232

    It also eliminates the need for a NULL modem (see section 5.12), and automatically programs the modem to the proper configuration. Also, if the telephone lines are poor, Modem Manager acts as a line buffer, making the communication more reliable. Electro Industries/GaugeTech 5-21 Doc #: E107-7-06-121...

  • Page 66: Programming Modems For Remote Communication

    • When programming the remote modem with a terminal program, make sure the baud rate of the terminal program matches the Nexus Monitor’s baud rate. Electro Industries/GaugeTech 5-22 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 67: Selected Modem Strings

    15VDC. No user programming is necessary to use either wet or dry field contacts. Optional 150V Max for wet contacts Figure 5.20: High Speed Inputs Connection Electro Industries/GaugeTech 5-23 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 68: Irig-B Connections

    Connect the (+) terminal of the Nexus Monitor to the (+) terminal of the signal generating device; connect the (-) terminal of the Nexus Monitor to the (-) terminal of the signal generating device. Nexus IRIG-B Port IRIG-B Time Signal Generating Device Figure 5.21: IRIG-B Connection Electro Industries/GaugeTech 5-24 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 69: Chapter 6: Using The Nexus External Displays

    Use the LEFT/RIGHT arrows to scroll from Reading to Reading within each Group. Use the Nexus Communicator software to Flash Update the P40N External Display. LED Display Left/Right Arrows Up/Down Arrows Mode Button Figure 6.1: Nexus P40N LED External Display Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 70: Dynamic Readings Mode

    Fixed Window Average Maximum +kWatt/+kVAR/CoIn kVAR • Predictive Sliding Window Maximum +kWatt/+kVAR/CoIn kVAR Group 5:VA/PF/Frequency (Use the LEFT/RIGHT arrows to access the following readings, in order.) • kVA/PF lag/Hz • Maximum kVA/Hz • Minimum kVA/Hz Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 71 • • Group 9: Phase Angles (Use the LEFT/RIGHT arrows to access the following readings, in order.) • Phase Angle Van/bn/cn • Phase Angle Ia/b/c • Phase Angle Vab/bc/ca • Phase Sequence Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 72: Navigational Map Of Dynamic Readings Mode

    First kVAhr Q2+Q3 Reading Return to First Reading Phase Angles V Phase Angles I Phase Angles V Phase Return to First AN,BN,CN A,B,C A,B,C Sequence Reading e Electro Industries/GaugeTech Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 73: Nexus Information Mode

    Group 5: Firmware Versions and Serial Numbers (Use the LEFT/RIGHT arrows to access the following readings, in order.) • RunTime External Display/RunTime DSP/RunTime Comm • Boot External Display/Boot DSP/Boot Comm • Serial Number External Display; Serial Number Nexus Monitor Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 74: Navigational Map Of Nexus Information Mode

    Port 3 Port 4 Port 1 Return PT Ratio CT Ratio First Reading Display Primary/Secondary Return Serial # Run-time Boot Display, Serial Display, Display, First # Monitor DSP, Comm DSP, Comm Reading Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 75: Display Features Mode

    Press Enter to turn the scroll feature on or off. When the scroll feature is on, the P40N External Display will scroll through the first reading of each group in the Dynamic Readings Mode. If a button is pressed during the scroll, scrolling pauses for one minute. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 76: Navigational Map Of Display Features Mode

    6.8: Navigational Map of Display Features Mode Use UP/DOWN arrows to scroll between groups. Reset Max/Min Reset Energy Baud Rate/Address Communication Protocol EIG Use Only EIG Use Only Lamp Test Display Scroll On/Off Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 77: Nexus P60N Touch Screen External Display

    Groups of Readings Reset Button View Limits View / Change Settings Figure 6.2: Nexus P60N Touch Screen External Display VOLTS: Voltage Readings Details • Volts AN/BN/CN/AB/BC/CA • Maximum Volts AN/BN/CN/AB/BC/CA • Minimum Volts AN/BN/CN/AB/BC/CA Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 78 +kVAhr Quadrant 2 (Primary) • +kVARhr Quadrant 2 (Primary) • +kVAhr Quadrant 3 (Primary) • -kVARhr Quadrant 3 (Primary) • +kWatthr Quadrant 1+Quadrant 4 (Primary) • +kVAhr for all Quadrants (Primary) Electro Industries/GaugeTech 6-10 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 79 • Phase Angle Vab/bc/ca WAVEFORM: Real Time Waveform Graph. Use Channel button to view graphs and readings: • Channel Van/bn/cn • Channel Ia/b/c • % THD, KFactor, Frequency for selected channel Electro Industries/GaugeTech 6-11 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 80 LCD Screen Settings: Contrast. Touch Up/Down buttons to increase/decrease settings. Number 37 is optimum setting. Backlight Off Delay (number of seconds after use that backlight turns off). Touch Up/Down buttons to increase/decrease settings. Electro Industries/GaugeTech 6-12 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 81 Port 2 (Baud and Protocol selected). Port 3 (Baud and Protocol selected). Port 4 (Baud and Protocol selected). • Nexus Status: Device Type: Nexus 1250 Serial Number (10 digit number) Comm State: Healthy or Unhealthy Nv Ram: 4 MB DSP State: Healthy or Unhealthy...

  • Page 82: Navigational Map For P60N Touch Screen External Display

    6.10: Navigational Map for P60N Touch Screen External Display 6.10: Navigational Map for P60N Touch Screen External Display Electro Industries/GaugeTech 6-14 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 83: Introduction

    These compensation values are added to the measured Watts and Vars for delivered power and subtracted from the same quantities for received power. The Values for %LWFE, %LWCU, %LVFE, %LVCU are derived from the transformer and meter information, as demonstrated in following sections. Electro Industries/GaugeTech Doc #: E107-6-07-121 Courtesy of NationalSwitchgear.com...

  • Page 84: Nexus 1250 Transformer Loss Compensation

    7.2: Nexus 1250 Transformer Loss Compensation 7.2: Nexus 1250 Transformer Loss Compensation The Nexus 1250 provides compensation for all metered and derived quantities by performing the numerical calculations described in section 7.5, Calculating Transformer Loss Compensation Percentages (Work Sheet). Enter the derived values in the Device Profile screen of the Nexus Communicator software.

  • Page 85: Loss Compensation Percentages

    • %LWFE—Percent Loss of Watts due to Iron • %LWCU—Percent Loss of Watts due to Copper • %LVFE—Percent Loss of Vars due to Iron • %LVCU—Percent Loss of Vars due to Copper Electro Industries/GaugeTech Doc #: E107-6-07-121 Courtesy of NationalSwitchgear.com...
  • Page 86 The following equation gives Primary Current at Rated Bank KVA and Test Phase Voltage. This value is used in calculating Copper Watt and Var losses, above. • Primary Current at Rated Bank KVA and Test Phase Voltage = (Bank KVA Rating/Test Phase Voltage) x SQRT (3) Electro Industries/GaugeTech Doc #: E107-6-07-121 Courtesy of NationalSwitchgear.com...
  • Page 87 No Load Loss KVA = (Exciting Current x Bank KVA Rating At this point, by working backwards from the Transformer and Nexus Monitor information, it is possible to derive values for %LWFE, %LWCU, %LVFE AND %LVCU. Electro Industries/GaugeTech Doc #: E107-6-07-121 Courtesy of NationalSwitchgear.com...

  • Page 88: Application Of Load Loss Compensation Percentages

    • Total 1 Sec Watts = Total 1 Sec Watts + Loss WCU + Loss WFE • Total 1 Sec Vars = Total 1 Sec Vars + Loss VCU + Loss VFE Electro Industries/GaugeTech Doc #: E107-6-07-121 Courtesy of NationalSwitchgear.com...

  • Page 89: Calculating Transformer Loss Compensation Percentages (Work Sheet)

    Watt Losses (FE) = ((120 x VTR)/Test Phase Voltage) x No Load Loss Watts = ((120 x ______)/__________________) x ________________ Var Losses (FE) = ((120 x VTR)/Test Phase Voltage) x No Load Loss Vars = ((120 x ______)/__________________) x ________________ Electro Industries/GaugeTech Doc #: E107-6-07-121 Courtesy of NationalSwitchgear.com...
  • Page 90 (VAR Losses (FE) (KW) x 100)/Nominal Primary KVA (_____________________ x 100)/____________ %LWCU (Watt Losses (CU) (KW) x 100)/Nominal Primary KVA (_____________________ x 100)/____________ %LVCU (VAR Losses (CU) (KW) x 100)/Nominal Primary KVA (_____________________ x 100)/____________ Electro Industries/GaugeTech Doc #: E107-6-07-121 Courtesy of NationalSwitchgear.com...

  • Page 91: Chapter 8: Nexus Time-Of-Use

    A Time-of-Use (TOU) usage structure takes into account the quantity of energy used and the time at which it was consumed. The Nexus 1250 TOU function, available with the Nexus Communicator software, is designed to accommodate a variety of programmable rate structures. Nexus TOU accumulates data based on the time-scheme programmed into the Nexus Monitor.

  • Page 92: Tou Prior Season And Month

    Sunday in October at 1:59:59 (to 1:00:00). See the Nexus Communicator User Manual. Or, you can use Auto DST, which sets Daylight Savings Time automatically (for the United States ONLY). You must also select a fixed or sliding window average method for the accumulation values. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 93: Chapter 9: Nexus External I/O Modules

    Mounting Brackets (MBIO): used to secure one or more modules to a flat surface. Mounting Brackets (MBIO) Female RS-485 Side Port LEDs I/O Port (Size and pin configuration vary) Male RS-485 Side Port Reset Button Figure 9.1: I/O Module Components Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 94: Installing Nexus External I/O Modules

    LED’s A(+) B(-) S - V + Male Side Port on Nexus I/O Module Nexus Monitor Port 4 + V - S B(-) A(+) Figure 9.2: Nexus Monitor Connected to I/O Module Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 95: Using Multiple I/O Modules

    I/O Port (Size and pin configuration vary) I/Os must use the Nexus Monitor’s Port 4. Group of 3 I/Os Set the port to 57600 Baud, Master. RS-485 Cable Nexus 1250 Addr Addr Addr Figure 9.3: Multiple I/Os Each I/O module in a group must be assigned a unique address. See the Nexus Communicator User Manual for details on configuring and programming the I/O Modules.

  • Page 96: Factory Settings And Reset Button

    8AI3 0–5 VDC, 8-Channel Analog Input 8AI4 0–10 VDC, 8-Channel Analog Input 4RO1 4 Latching Relay Outputs 4PO1 4 KYZ Pulse Outputs 8DI1 8 Digital Status Inputs (Wet/Dry) 4RTD1 4 RTD Inputs Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 97: Analog Transducer Signal Output Modules

    All outputs share a single common point. This is also an isolated connection (from ground). The figure on the next page shows the configuration of the Analog Output Module’s I/O Port, which is used for connection to an interface device. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 98 I/O Port on 8-Channel Analog Interface Device Output Module (SCADA, RTU, etc) OUT 1 OUT 2 OUT 3 OUT 4 OUT 5 OUT 6 OUT 7 OUT 8 Bottom RESET Figure 9.4 Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 99: Analog Input Modules

    All inputs share a single common point. This is also an isolated connection (from ground). The figure on the next page shows the configuration of the Analog Input Module’s I/O Port, which is used for connection to an interface device. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 100 I/O Port on 8-Channel Analog Input Module Interface Device INPUT 1 INPUT 2 INPUT 3 INPUT 4 INPUT 5 INPUT 6 INPUT 7 INPUT 8 RESET Bottom Figure 9.5 NOTE: Dashed lines indicate customer wiring. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 101: Digital Dry Contact Relay Output (Form C) Module

    The figure on the next page shows the configuration of the Output Module’s I/O Port, which is used for connection to an interface device. Each latching relay will hold its state in the event of a power loss. Electro Industries/GaugeTech Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 102 Digital Dry Contact Relay Module (I/O Port) I/O Port on Digital Dry Contact Relay Module Output 1 Output 2 Output 3 Output 4 RESET Bottom Figure 9.6 Electro Industries/GaugeTech 9-10 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 103: Digital Solid State Pulse Output (Kyz) Module

    The figure on the next page shows the configuration of the KYZ Pulse Module’s I/O Port, which is used for connection to an interface device. NC = Normally Closed; NO = Normally Open; C = Common. Electro Industries/GaugeTech 9-11 Doc #: E107-7-06-121...
  • Page 104 I/O Port on Digital Solid State Pulse Output (KYZ) Module Output 1 Output 2 Output 3 Output 4 RESET Bottom Figure 9.7 NOTE: Relay contact positions are shown in shelf (de-energized) state. Electro Industries/GaugeTech 9-12 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 105 This module is used for either additional status detect or for accumulating pulses from external equipment, such as power meters, water meters, etc. A user programmable address and functionality afford versatility. Electro Industries/GaugeTech 9-13 Doc #: E107-7-06-121...
  • Page 106 Digital Status Input Module, I/O Port I/O Port on Digital Status Input Module INPUT 1 INPUT 2 INPUT 3 INPUT 4 INPUT 5 INPUT 6 INPUT 7 INPUT 8 RESET Bottom Figure 9.8 Electro Industries/GaugeTech 9-14 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 107: Chapter 10: Nexus Monitor With Internal Modem Option

    (See section 5-14 for repeater details.) RS-485 RJ-11 Daisy Chain Originate Modem (or Internal to PC) Figure 10.1: Nexus with Internal Modem Option Electro Industries/GaugeTech 10-1 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 108: Hardware Connection

    Master and an RS-485 connection to any port on the remote Nexus. The Address of the remote Nexus MUST be something other than “1”. The link using RS-485 is capable for up to 4000 feet (1219 meters). Electro Industries/GaugeTech 10-2 Doc #: E107-7-06-121...

  • Page 109: Chapter 11: Nexus Monitor With Internal Network Option

    Monitors. A daisy chain can have up to 31 meters. If more are desired, the installation of a repeater allows additional meters. (See section 5-14 for repeater details.) MODBUS/RTU RS-485 10 BASE-T RJ-45 MODBUS/TCP over Ethernet Daisy Chain Network Figure 11.1: Nexus with Internal Network Option Electro Industries/GaugeTech 11-1 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...
  • Page 110 You can access the Nexus with SCADA, MV90 and RTU all at the same time. The Internal Network Option allows multiple users running Nexus Communicator software to access the meter concurrently. Electro Industries/GaugeTech 11-2 Doc #: E107-7-06-121 Courtesy of NationalSwitchgear.com...

  • Page 111: Hardware Connection

    The Address of the remote Nexus MUST be something other than “1”. “1” is reserved for the Nexus connected to the network via its RJ-45. The link using RS-485 is capable for up to 4000 feet (1219 meters). Electro Industries/GaugeTech 11-3 Doc #: E107-7-06-121...
  • Page 112 GLOSSARY OF TERMS Term Definition 0.1 Second Values These values are the RMS values of the indicated quantity as calculated after approximately 50 milliseconds (3 cycles) of sampling. 1 Second Values These values are the RMS values of the indicated quantity as calculated after one second (60 cycles) of sampling.
  • Page 113 Term Definition DNP 3.0 A common protocol used in electric utility substations and SCADA systems. Ethernet A type of LAN network connection that connects two or more devices on a common communications backbone. An Ethernet LAN consists of at least one hub device (the network backbone) with multiple devices connected to it in a star configuration.
  • Page 114 Term Definition NVRAM NVRAM (Non-volatile Random Access Memory) is able to keep the stored values in memory even with the loss of circuit or control power. High speed NVRAM is used in the Nexus to gather measured information and to insure that no information is lost.
  • Page 115 Term Definition Sliding Window The Sliding Window Average is the average power calculated Average (Power) over a user-set time interval that is derived from a specified number of sub-intervals, each of a specified time. For example, the average is calculated over a 15-minute interval by calculating the sum of the average of three consecutive 5-minute intervals.

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