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Nexus 1250/1252 Meter Power Monitor User Manual

1. G 5 BW OO000 OO x RT RT a 120 Ohms TE 120 Ohms RT hk T 120 Ohms l i l I 1 el ies Po ge I l 1 I l I l RS232 ir ro Extension l l Cable ji 1 1 Wiring a l I l l I l I l I 7 gt I a l H I l 1 1 l OOE RTE 3 ANR S ages 120 Ohms i 120 Ohms l 120 Ohms J i i Ie of tC ese Ss 1 TE 1 ot 14 I l 1 I I I i I I l f l l I i rot Koa ot ix ii ot It ot rt I cous oo0oo0o0o0 oOoo0oo0oojjooooolooooojllioooo0oo0oo0o0o0o0joo0 O O 4V S 4V S 4V S V S 876543210 Port 1 Port 2 Port 3 Port 4 High Speed Inputs IRIG B RS232 RS485 Selectable Figure 5 3 Communication Wiring NOTES e I O Modules and External Displays require power connections to the Voltage terminals dashed lines e For all communications S Shield This connection is used to reference the Nexus meter s port to the same potential as the source It is not an earth ground connec tion You must also connect the shield to earth ground at one point Cj Electro Industries GaugeTech Doc E107706 e3 The Leader In Power Monitoring and Smart Grid Solutions 5 Communicat
2. Mounting Bracket Mounting Bracket 6 879 13 088cm coal ps a a raza M 17 V7 4 000 O00 000 _ 1 On Powerin B e eo ol jno of o of ZN Wey 3 437 8 729cm j Powe ad ol o e ower QUPPIY lt p 2 200 5 588cm o oj of Max Power 12VA 7 J l Input Voltage 12 60V DC O 1 100 2 54cm eop e 90 240v Ac Dc O a oj e Output Voltage 12V DC o eo o o o Aae aon 618 1 570cm 1 301 3 305cm Figure 3 7 I O Modules Mounting Diagram Front View i Electro Industries GaugeTech Doc E107706 3 6 The Leader In Power Monitoring and Smart Grid Solutions 4 Electrical Installation 4 Electrical Installation This chapter provides electrical installation information for the Nexus 1250 1252 meter 4 1 Considerations When Installing Meters Installation of the Nexus 1250 1252 meter must be performed only by qualified personnel who follow standard safety precautions during all procedures Those personnel should have appropriate training and experi ence with high voltage devices Appropriate safety gloves safety glasses and protective clothing are recommended During normal operation of the Nexus meter dangerous voltages flow through many parts of the unit including Terminals and any connected CTs Current Trans formers and PTs Potential Transformers all 1 O Modules and their circuits All Primary and Secon
3. 000 000 000 000 EXUS 1250 Vou viet Te Vi j Originate Modem or internal to PC Figure 5 1 RJ11 Communication with Internal Modem Option 3 Electro Industries GaugeTech Doc E107706 5 1 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring RJ45 Network Connection allows a Nexus 1250 1252 meter with the Internal Network Option INP200 to communicate with multiple PC s simultaneously No other hardware is necessary for this easy to use connection In a Nexus meter with INP200 Port 2 becomes a Gateway for connecting multiple Nexus meters using RS485 See Chapter 11 for INP200 details Modbus TCP Over Ethernet Internet rU Un ET tl 000 000 000 000 NEXUS 1250 ihsas vene veer LOpOHOGO FIR Pleel IPIE S N Noo E Figure 5 2 RJ45 Communication with Internal Network Option NOTE Nexus 1252 meters can also communicate with DNP 3 0 protocol over Ethernet Cj Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring RS485 Master P40N I O Module Unicom or External Display Modem Manager
4. Voltage Input Withstand Capability Meets ANSI C37 90 1 Surge withstand capability Voltage inputs optically isolated to 2500VDC Input Current Range 10A Max Programmable to any CT Ratio Fault Current recording to 60A peak secondary based on 5A Full Scale NOTE 1A and 0 25A current inputs are available by special order Current Input Terminals 8 32 Threaded Studs The current inputs are only to be connected to external current transformers Current Input Withstand Capability at Continuous rating 20A 23 Surge 100A 10 secs 300A 3 secs 500A 1 sec Burden Voltage 0 05VA 120V rms Current 0 002VA 5A rms Isolation All inputs and outputs 2500V All Com ports are isolated from each other Sensing Method RMS g Electro Industries GaugeTech Doc E107706 l The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview Specification Nexus meter Update Time 200msec High speed readings 1 sec Revenue accurate reading Frequency Range Fundamental 20 65Hz Up to 255th Harmonic Measuring Capability Dimensions HxWxL 3 4 x 7 3 x 10 5 in 8 6 x 18 5 x 26 6 cm Maximum Power Consumption 40 Watts with optional modules and display Nominal Power Consumption Approximately 12 Watts without optional modules or display Operating Temperature 40 to 70 C 40 to 158 F Auxiliary Output Po
5. Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays 6 4 Navigation Map of Dynamic Readings Mode e Use Left Right arrow keys to navigate Readings e Use Up Down arrows to scroll between groups Reading A tO 1 Second Volts AN BN CN 1 Second Volts Maximum Volts AN BN CN Minimum Volts Minimum Volts AN BN CN Maximum Volts THD Volts AN BN CN Return to Max THD Volts AN BN CN Min THD Volts AN BN CN Return to First Reading First Reading AB BC CA AB BC CA AB BC CA Return to First Reading Minimum IA IB IC 1 Second IA IB IC 1 Second INc INm Maximum IA IB IC Max kWatt kVAR CoIn kVAR Max kWatt kVAR CoIn Return to First Reading Block WinAvg Max k Watt kVAR CoIn kVAR Pred Roll Win Avg k Watt kVAR CoIn kVAR 1 Second kWatt KVAR 1 Second kVA PF lag Frequency Return to First Reading Positive Positive Negative kWatthour kVARhr kVARhr Q1 Q4 Q1 Q4 Return to First Reading Return to First Reading Negative Positive Negative kWatthr KVARhr KVARhr Q2 Q3 Q2 Q3 2 2 kI tB kI tC Phase Angles V AB BC CA Return to First Reading 2 2 2 2 kI tA kV tA kV tB kV tC lt iirc Phase Angles V Phase Return to First Reading Phase Angles I AN BN CN A B C Sequence Cj Electro Industries GaugeTech Doc E107706 Th
6. Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 Transformer Loss Compensation Calculate Load Loss Values Quantity Value at Meter Base Loss at Quantity Meter Base kVA Meter Base No Load Loss Loss kW Watts FE No Load Loss Loss kVAR VARs FE Load Loss Loss kW Watts CU Load Loss Loss kVAR VARs CU Enter Value at Meter Base from Normalize Losses section Enter Meter Base kVA from previous calculation Calculate Loss at Meter Base by dividing Value at Meter Base by Meter Base kVA and multiplying by 100 Enter calculated Loss Watts values into the Nexus meter using Communicator EXT software Refer to Appendix B of the Communicator EXT User Manual for instructions Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 Transformer Loss Compensation This page intentionally left blank Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 8 Time of Use Function 8 Time of Use Function 8 1 Introduction 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 1252 meter s TOU func tion available with the Communicator EXT software is designed to accommodate a variety of programmable rate str
7. _ _ _ Frequency Base Current Base Yoltage Flicker M onitoring Polling Flicker Countdown Main screen This section describes the Main Screen functions These functions are found on the left side of the screen Time Start Reset is the time when Flicker was started or reset A Reset of Flicker causes the Max Min values to be cleared and restarts the Flicker Pst and Plt timers A Start of Flicker is also equivalent to a Reset in that the PST and PLT are restarted and the Max Min Values are cleared e Stop corresponds to the time when Flicker is turned off e Current is the current clock time e Next Pst is the countdown time to when the next Pst value is available e Next Pit is the countdown time to when the next Plt value is available 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 6 12 Flicker and Analysis Status e This screen indicates the current status Active On Stopped Off Frequency e Base is the operating frequency 50 or 60 Hz selected in the EN50160 Flicker screen see Section 12 3 e Current is the real time frequency measurement of the applied voltage Base Voltage e This field shows the normalized voltage for the selected frequency 230 V for 50 Hz or 120 V for 60 Hz Flicker Monitoring e Clicking on Stop causes Flicker to stop being processed and freezes all the current
8. 13 Substation Rack Mount Assembly w Switch Displays connected to meter s Port 3 Port 1 Serial Connection going to front of the unit Figure 13 3 Back of Rack Assembly POT CURRENT POT CURRENT POT CURRENT POT DC SUPPLY A A B B c c N Low High Low High Low High Figure 13 4 Detail of Test Switches a Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 13 4 Glossary Glossary 0 2 Second Values These values are the RMS values of the indicated quantity as calculated after approximately 200 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 Alarm An event or condition in a meter that can cause a trigger or call back to occur Annunciator A short label that identifies particular quantities or values displayed for example kWh Average Current When applied to current values Amps the average is a calculated value that corresponds to the thermal average over a specified time interval The interval is specified by the user in the meter profile The interval is typically 15 minutes So Average Amps is the thermal average of Amps over the previous 15 minute inter
9. 6 Using the External Displays e Run Time External Display Run Time DSP RunTime Comm e Boot External Display Boot DSP Boot Comm e Serial Number External Display Serial Number Nexus Monitor 6 6 Navigation Map of Nexus Information Mode e Use Left Right arrow keys to navigate Readings Use Up Down arrows to scroll between groups Readings Meter Time ooco73g Comm Comm Comm Settings Settings Settings Port 1 Port 2 Port 3 Return CT Ratio To First Reading PT Ratio Display Primary Secondary Run time Boot Serial Display Serial Monitor Display Display Comm Return Settings To Port 4 First Reading Return To First Reading Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 6 Using the External Displays 6 7 Display Features Mode Use the Mode button to access the Display Features Mode from other modes Use the Up Down arrows to navigate from group to group within this mode See Section 6 8 for a Navigation map of the Display Features mode Group 1 Reset Max Min Press Enter to reset the Max and Min values NOTE If the Password Protection feature has been enabled through Communicator EXT software you will need to enter a password to reset the Max Min readings Follow this procedure 1 Press Enter 2 Enter the password one character at a time by pressing the Up or Down arrows Each password character beg
10. CO CO 09 NNNNN WNNF FE Ou Re pe 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 TOC 2 Table of Contents 9 External I O Modules 9 1 Hardware Overview 9 1 1 Port Overview 9 2 I O Module Installation 9 2 1 Power Source for I O Modules 9 3 Using the PSIO with Multiple I O Modules 9 3 1 Steps for Attaching Multiple I O Modules 9 4 Factory Settings and Reset Button 9 5 Analog Transducer Signal Output Modules 9 5 1 Overview 9 1 9 1 9 2 9 3 9 3 9 4 9 5 9 5 9 6 9 7 9 5 2 Normal Mode 9 7 9 6 Analog Input Modules 9 8 9 6 1 Overview 9 8 9 6 2 Normal Mode 9 9 9 7 Digital Dry Contact Relay Output Form C Module 9 10 9 7 1 Overview 9 10 9 7 2 Communication 9 11 9 7 3 Normal Mode 9 11 9 8 Digital Solid State Pulse Output KYZ Module 9 12 9 8 1 Overview 9 12 9 8 2 Communication 9 13 9 8 3 Normal Mode 9 13 9 9 Digital Status Input Module 9 15 9 9 1 Overview 9 15 9 9 2 Communication 9 16 9 9 3 Normal Mode 9 16 10 Meter with Internal Modem Option I NP2 10 1 10 1 Hardware Overview 10 1 10 2 Hardware Connection 10 1 10 3 Dial In Function 10 2 10 4 Dial Out Function 10 2 11 Meter with I nternal Network Option INP200 11 1 11 1 Hardware Overview 11 1 11 2 Network Connection 11 2 12 Flicker and Analysis 12 1 12 1 Overview 12 1 12 2 Theory of Operation 12 1 12 2 1 Summary 12 3 12 3 Flicker Setting Nexus 1250 meter and
11. Use Up Down arrows to scroll between groups ooco73a Reset Max Min Reset Energy Baud Rate Address Communication Protocol Display Scroll On Off Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 Transformer Loss Compensation 7 Transformer Loss Compensation 7 1 Introduction The Edison Electric Institute s Handbook for Electricity Metering Ninth Edition defines Loss Compensation as A means for correcting the reading of a meter when the metering point and point of service are physically separated resulting in measurable losses including I2R losses in conductors and transformers and iron core losses These losses may be added to or subtracted from the meter registration Loss compensation may be used in any instance where the physical location of the meter does not match the electrical location where change of ownership occurs Most often this appears when meters are connected on the low voltage side of power trans formers when the actual ownership change occurs on the high side of the trans former This condition is shown pictorially in Figure 7 1 Ownership Change Figure 7 1 Low Voltage Metering Installation Requiring Loss Compensation It is generally less expensive to install metering equipment on the low voltage side of a transformer and in some conditions other limitations may also impose the require ment of low side
12. values Stop Time is recorded and the current Max Min values are cleared e Clicking on Start starts Flicker processing Start Time is recorded e Clicking on Reset causes the Max Min values to be cleared and restarts the Flicker Pst and Plt timers Use the tabs at the top of the screen to navigate to the Instantaneous Short Term and Long Term Readings views shown on the right side of the screen Instantaneous Readings NOTE The Instantaneous view is the default of this screen See the screen pictured on the previous page If you are in the Short or Long Term views click on the Instan taneous tab to display this view e The PU values Pinst for Voltage Inputs Va Vb and Vc are displayed here and are continuously updated The corresponding Current Voltage values for each channel are displayed for reference 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 7 12 Flicker and Analysis Short Term Readings Click on the Short Term tab to access a screencontaining three groups of Pst readings shown below EN50160 IEC 61000 4 ENE Time Start Reset Stop Current Next PST Next PLT Pst readings displayed 30 Flicker PST Time VoltsA _ Volts B z Voice 0 212 Max Volts A Max Volts B L MaxVoltsC 251 E Min VoltsA 2729 2010 14 20 00 25 Min Volts B Min Volts C Base Voltage Flicker Monito
13. 9 7 1 Overview The Relay Output Module consists of four Latching Relay Outputs In Normal Mode the device accepts commands to control the relays Relay output modules are triggered by limits programmed with the Communicator EXT software See the Communicator EXT User Manual for details on programming limits The Nexus 1250 1252 meter supplies power for up to 4 connected Relay Output modules See Section 9 2 for power and communication details Refer to Section 5 6 2 to determine if you must use an additional power source such as EIG s PSIO 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 10 9 External I O Modules The Modbus Map for the Analog Output Module and operating details can be found in the Modbus Communicating O Modules Manual Each latching relay will hold its state in the event of a power loss 9 7 2 Communication Maximum registers per request read or write is 4 registers The device will operate with the following default parameters Address 247 F7H Baud Rate 57600 Baud Transmit Delay Time 20 msec Some situations will cause the device to operate with the above Default Parameters See Section 9 4 for details of Default Mode 9 7 3 Normal Mode Normal Mode consists of one process the device accepts new commands to control the relays Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solut
14. The meter uses the combination of the add subtract setting and the directional definition of power flow also in the profile to determine how to handle the losses Losses will be added to or subtracted from depending on whether add or subtract is selected the Received Power flow For example if losses are set to Add to and received power equals 2000 kW and losses are equal to 20kW then the total metered value with loss compensation would be 2020 kW for these same settings if the meter measured 2000 kW of delivered power the total metered value with loss compensation would be 1980 kW Since transformer loss compensation is the more common loss compensation method the meter has been designed for this application Line loss compensation is calculated in the meter using the same terms but the percent values are calculated by a different methodology Nexus Meter Transformer Loss Compensation e Performs calculations on each phase of the meter for every measurement taken Unbalanced loads are accurately handled e Calculates numerically eliminating the environmental effects that cause inaccura cies in electromechanical compensators e Performs Bidirectional Loss Compensation e Requires no additional wiring the compensation occurs internally e Imposes no additional electrical burden when performing Loss Compensation 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7
15. e All Nexus meters are equipped with internal clock crystals which are accurate to 20ppm and which can be used if IRIG B is not connected and or Line Frequency Clock Synchronization is not enabled DNP Time Synchronization e Using Communicator EXT you can set the meter to request time synchronization from the DNP Master Requests can be made from once per minute to once per day See the Nexus 1252 1262 1272 1500 DNP User Manual for instructions You can download the manual from EIG s website www electroind com pdf DNPv3 0_Level2 pdf Other Time Setting Tools e Tools gt Set Device Time For manual or PC time setting e Script amp Scheduler Time stamps retrieved logs and data Cj Electro Industries GaugeTech Doc E107706 5 20 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring e MV90 Can synchronize time on retrievals in the form of a Time Stamp Refer to the Communicator EXT User Manual HHF Converter for more MV 90 details Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring This page intentionally left blank Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 6 Using the External Displays 6 Using the External Displays This chapter provides information on the Nexus 1250 1252 meter s external displays 6 1 Ove
16. 2 Wire RS485 Port Detail All of the Nexus 1250 1252 meter s RS485 ports have the following connections e V Voltage terminals for power connections use with Nexus I O Modules and Displays only The Nexus 1250 1252 meter supplies 17V DC through the V terminal connections NOTE Do not connect these pins to devices that receive power from another source e g a computer or to devices that do not require power to operate e S Shield the Shield connection is used to reference the meter s port to the same potential as the source It is not an earth ground connection You must also connect the shield to earth ground at one point Do not connect the shield to ground at multiple points as this will interfere with communication Two wire RS485 communication terminals connect the terminal of the Nexus meter s port to the terminal of the device connect the terminal of the Nexus meter s port to the terminal of the device NOTES on RS485 Communication e Use a shielded twisted pair cable 22 AWG 0 33 mm2 or larger grounding the shield at one end only e Establish point to point configurations for each device on an RS485 bus connect terminals to terminals connect terminals to terminals e Protect cables from sources of electrical noise 3 Electro Industries GaugeTech l Doc E107706 Sus The Leader In Power Monitoring and Smart Grid Solutions 5 Communication
17. Optional 15 2 9 Nexus 1250 1252 Meter Specifications 17 2 10 Nexus P40N P41N P43N LED External Display Specifications 18 2 11 Upgrading the Nexus 1252 Meter s V Switch Key 19 3 Hardware Installation 3 1 3 1 Mounting the Nexus 1250 1252 Meter 3 1 3 2 Mounting the Nexus LED External Displays 3 2 3 3 Mounting the Nexus External I O Modules 3 5 4 Electrical Installation 4 1 4 1 Considerations When Installing Meters 4 1 4 2 Wiring the Monitored Inputs and Voltages 4 3 4 3 Fusing the Voltage Connections 4 3 4 4 Wiring the Monitored Inputs VRef 4 3 4 5 Wiring the Monitored Inputs VAux 4 3 4 6 Wiring the Monitored Inputs Currents 4 3 4 7 Isolating a CT Connection Reversal 4 5 4 8 Instrument Power Connections 4 5 g Electro Industries GaugeTech Cj The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 TOC 1 Table of Contents ca fon 4 9 Wiring Diagrams 5 Communication Wiring 5 1 Communication Overview 5 2 RS232 Connection Port 1 5 3 RS485 Communication 5 3 1 RS485 Connection 5 3 2 Connection to an RS485 Master Unicom or Modem Manager 5 3 3 Using the Unicom 2500 5 3 4 RS485 Connection to the Nexus P40N External Display 5 4 RJ11 Telephone Line Connection Nexus Meter with Internal Modem Option INP2 to a PC 5 5 RJ45 Connection Nexus Meter with Internal Network Option AAAA Li OONN A REE uI I j oO INP200 to multiple PCs 10 1
18. Potential Transformers Current Transformers Power Multiplier PT Multiplier x CT Multiplier Enter the Numerator and Denominator for each instrument transformer For example a PT with a ratio of 7200 120 has a numerator or 7200 a denominator or 120 and a multiplier of 60 7200 120 60 1 Meter Secondary Voltage Volts 120 Meter Secondary Current Amps 5 Base Conversion Factors Quantity Trans Multiplier Trf IT Sec Meter Base Meter Trf former Voltage 120 Current 5 For Transformer Voltage enter the Phase to Neutral value of Test Voltage previously calculated For Transformer Current enter the Full Load Current previously calcu lated For Multipliers enter the PT and CT multipliers previously calculated TrfIT Secondary is the Base Value of Voltage and Current at the Instrument Trans former Secondary of the Power Transformer These numbers are obtained by dividing the Transformer Voltage and Current by their respective Multipliers The Meter Trf values for Voltage and Current are obtained by dividing the Meter Base values by the TrfIT Secondary values 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 8 7 Transformer Loss Compensation Load Loss at Transformer No Load Loss Watts kW 1 Phase kW No Load Loss No Load Loss VA kVA Exciting Curre
19. the ground is not at the center of the delta Figure 1 4 shows the phasor relationships between voltage and current on a three phase delta circuit In many delta services one corner of the delta is grounded This means the phase to ground voltage will be zero for one phase and will be full phase to phase voltage for the other two phases This is done for protective purposes 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 4 1 Three Phase Power Measurement VaB Figure 1 4 Phasor Diagram Three Phase Voltages and Currents Delta Connected Another common delta connection is the four wire grounded delta used for lighting loads In this connection the center point of one winding is grounded On a 120 240 volt four wire grounded delta service the phase to ground voltage would be 120 volts on two phases and 208 volts on the third phase Figure 1 5 shows the phasor diagram for the voltages in a three phase four wire delta system Ve Vca Vec N Va VaB Ve Figure 1 5 Phasor Diagram Showing Three phase Four Wire Delta Connected System 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 5 1 Three Phase Power Measurement 1 1 3 Blondell s Theorem and Three Phase Measurement In 1893 an engineer and mathematician named Andre E Blondell set forth the first scientific basis for polyphase metering H
20. 12 10 the actual values of the current subinterval 12 10 12 11 and the prediction for the remainder of the subinterval 4 5 of the 120 of the 12 05 12 10 subinterval of Subintervals n Subinterval Length Len Partial Subinterval Length Cnt Prediction Factor Pct Sub Sub Subo Partial Predict Len Len Len Cnt Len Len Value Sub Len Cnt 1 5 Value Partial nt Cj Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview n 2 gt Value Len Cnt Partial lt ao ere n Len n 2 Se amei Ln 4 228 4 OE Sel y be Pet n 1 2x n 1 Len 2 8 Nexus External I O Modules Optional The following multiple analog or digital I O modules mount externally to the Nexus 1250 1252 meter The Nexus 1250 1252 meter supplies 12VA to its ports You may need to use additional power supplies such as EIG s 12V PSIO to extend I O capabil ity See Sections 5 6 2 to determine power needed see Section 3 3 for mounting diagrams and see Chapter 9 for details on installation and use of the Nexus External 1 O modules Analog Transducer Signal Outputs e 1mAON4 4 Analog Outputs self powered scalable bidirectional e 1ImAONB8 8 Analog Outputs self powered scalable bidirectional e 20mMAON4 4 Analog Outputs self powered scalable e 20MAONB8 8 Analog Outputs self pow
21. 120 Ohms but this value may vary based on length of cable run gauge or the impedance of the wire See RT EXPLANATION in Section 5 3 Master device Last Slave device N Slave device 1 Slave device 2 SH SH Twisted pair shielded SH cable Twisted pair shielded SH cable Twisted pair shielded SH cable Earth Connection preferably at single location Figure 5 9 Linking Multiple Nexus Meters in Series 3 Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 5 13 5 Communication Wiring You can use an RS485 repeater to network several links of instruments NOTES e A maximum number of 31 Nexus meters may be connected to one repeater e A maximum number of 31 repeaters may be included on the same network 5 8 Remote Communication Overview Either RJ11 INP2 Option or RJ45 INP200 Option can connect devices at great distances Section 5 1 gives an overview of these communication options Chapter 10 explains the INP2 Internal Modem Option Chapter 11 explains the INP200 Network Option You can use also use modems to connect devices EIG recommends using RS485 wiring with a Modem Manager See Section 5 8 2 for additional information 5 8 1 Remote Communication RS232 The link using RS232 is viable for up to 50 feet 15 2 meters Set the selector switch under Port 1 to RS232 Use an RS232 serial extension cable connected to the 9 pin female ser
22. 1252 V 1 12 4 12 4 Flicker Polling Screen 12 6 12 5 Logging 12 10 12 6 Polling through a Communication Port 12 10 12 7 Log Viewer 12 10 12 8 Performance Notes 12 11 12 9 EN50160 IEC61000 4 30 Power Quality Compliance Analysis Nexus 1252 meter with V 2 12 12 12 9 1 EN50160 1IEC61000 4 30 Configuration 12 12 12 9 2 EN50160 IEC61000 4 30 Analysis 12 14 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 TOC 3 Table of Contents 13 Substation 19 inch Rack Mount Assembly Nexus 1252 Meter 13 1 Overview 13 2 Features 13 3 Options 13 4 Dimensions 13 5 Installation 13 6 Wiring 13 7 Ordering Information Glossary 13 1 13 1 13 1 13 2 13 2 13 2 13 3 13 3 GL 1 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 TOC 4 1 Three Phase Power Measurement 1 Three Phase Power Measurement This introduction to three phase power and power measurement is intended to provide only a brief overview of the subject The professional meter engineer or meter technician should refer to more advanced documents such as the EEI Handbook for Electricity Metering and the application standards for more in depth and technical coverage of the subject 1 1 Three Phase System Configurations Three phase power is most commonly used in situations where large amounts of power will be used because i
23. Modules The Nexus 1250 1252 can supply power to a limited number of I O Modules and external displays For more modules you must use an external power source such as the EIG PSIO 12V Refer to Section 5 6 2 to determine power needed TX CT RX On 0 1mA Analog Input Power In Module COM N L INPUT 1 INPUT 2 DANGER i Power Supply INPUT 4 Max Power 12 VA Input Voltage 12 60V ocO 90 240v Ac Dc O Output Voltage 12V DC Electrolndustries GaugeTech www electroind com Figure 9 3 Power Flow from PSIO to I O Module Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 External I O Modules On Power In X NC L Power Supply Max Power 12 VA Input Voltage 12 60V DC 90 240V AC DC Output Voltage 12V DC Electroindustries GaugeTech www electroind com eee _ __ G Electro Industries Gaugetech lt POWER lt q POWER lt __ gt o lt c _ gt a Figure 9 4 PSIO Side and Top Labels Labels are Red and White 9 3 Using the PSIO with Multiple I O Modules LEDs Communication ONLY A B and Side Port O 1mi Analog O Modul jutput le ooo0oo0o 0 COM OUT1 OUT2 OUT3 OUT 4 Va O fal 0 O E 0 1mA Analog Input Module ooo0oo00
24. Nexus 1250 1252 LED displays model numbers P40N P41N and P43N mount using a standard ANSI C39 1 drill plan Secure the four mounting studs to the back of the panel with the supplied nuts Six feet of RS485 communication power cable harness is supplied Allow for at least a 1 25 inch 3 17cm diameter hole in the back for the cable harness See Chapter 5 for communication and power supply details The cable harness brings power to the display from the Nexus 1250 1252 meter which supplies 15 20V DC The P40N or P41N or P43N can draw up to 500mA in display test mode 3 Electro Industries GaugeTech Doc E107706 ee The Leader In Power Monitoring and Smart Grid Solutions 3 Hardware Installation 4 38 Sq 11 12 cm We S65 P4ON Front Dimensions P40N Side Dimensions P40N Display pi 5 274 13 40em a eal 5 274 13 40em Figure 3 3 Legacy P40N and P40N Dimensions 1 790 4 54cm 1 068 2 71cm 1 000 2 54cm a NOTE The P40N is not intended for new applications 75 1 438 Sq 1 91 3 65 cm cm I Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 3 Hardware Installation 3 9 18 5 2 c a 1 688 4x 0 200 4 28 cm 3 375 8 572cm 04 00 10 16cm Figure 3 4 ANSI C39 1 Drill Plan for P40N P40N Display Electro a a Doc E107706 The
25. PARTICULAR PURPOSE ELECTRO INDUSTRIES GAUGETECH SHALL NOT BE LIABLE FOR ANY INDIRECT SPECIAL OR CONSEQUENTIAL DAMAGES ARISING FROM ANY AUTHORIZED OR UNAUTHORIZED USE OF ANY ELECTRO INDUSTRIES GAUGETECH PRODUCT LIABILITY SHALL BE LIMITED TO THE ORIGINAL COST OF THE PRODUCT SOLD Cj Electro Industries GaugeTech Doc E107706 jii The Leader In Power Monitoring and Smart Grid Solutions Use of Product for Protection 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 Statement of Calibration Our instruments are inspected and tested in accordance with specifications published by Electro Industries GaugeTech The accuracy and a calibration of our instruments are traceable to the National Institute of Standards and Technology through equipment that is calibrated at planned intervals by comparison to certified standards For optimal performance EIG recommends that any meter including those manufac tured by EIG be verified for accuracy on a yearly interval using NIST traceable accu racy standards Disclaimer The information presented in this publication has been carefully checked for reliability however no responsibility is assumed for inaccuracies The information contained in this document is subject to change without notice Safety Symbols In this manual this symbol indicates that the operator must refer to a
26. Provide termination resistors at each end connected to the and lines RT is approximately 120 Ohms See RT EXPLANATION in Section 5 3 a 3 Electro Industries GaugeTech Doc E107706 5 9 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring 5 4 RJ 11 Telephone Line Connection Nexus Meter with Internal Modem Option INP2 to a PC Use RJ11 Standard Telephone Line to connect with the Nexus 1250 1252 meter For details on this connection see Chapter 10 5 5 RJ 45 Connection Nexus Meter with I nternal Network Option INP200 to Multiple PCs 10 100BaseT The Internal Network Option conforms to the IEEE 802 3 10BaseT and 100BaseT specification using unshielded twisted pair UTP wiring This allows the use of inexpensive RJ45 connectors and CAT 3 or better cabling For details on this connection see Chapter 11 5 6 Communication Ports on the Nexus I O Modules e Female RS485 Side Port use to connect to another module s female RS485 side port Male RS485 Side Port use to connect to the Nexus meter s Port 3 or Port 4 or to connect to another module s male RS485 side port I O Port use for functions specific to the type of module size and pin configuration varies depending on type of module For more detail refer to the following section and Chapter 9 Female RS485 Side Port I O Port Size and Pin Male RS485 Configuration Vary Side Port Figure
27. Rack Mount Assembly Nexuse 1252 Meter 13 1 Overview The Nexus 1252 meter can be ordered in a 19 inch rack mount assembly for use in modern substation control apparatus The assembly houses the Nexus 1252 meter a Test switch and three LED displays The assembly is pre wired and pre labeled for easy installation An example assembly is shown below Figure 13 3 shows the assem bly components from the back 13 1 Front of Rack Mount Assembly 13 2 Features e Ideal for substation 19 inch rack mount control panel applications e Incorporates three displays Amps Power and Volts e Has a front panel download port e Equipped with a built in Test switch accessed from the rear of the assembly a Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 13 1 13 Substation Rack Mount Assembly 13 3 Options The rack assembly is equipped with three LED displays e P40ON Master LED display providing either multifunction measurement or use as a Volts master unit The P40N is the standard display for the rack assembly e P41N An LED Amps display which is a slave display e P43N An LED Power display which is a slave display 13 4 Dimensions The dimensions for the Nexus 1252 rack assembly are e Length 19 inches 482 6mm e Height 7 inches 177 8 mm 4 Rack units e Depth 14 inches 355 6 mm 13 5 Installation The rack assembly is 4 Rack units high It has f
28. V for a 50 Hz frequency e Short Term Test Time Select the time in minutes for the PST short term test The available range is from 1 10 minutes f Long Term Test Time Select the time in minutes for the LST long term test The available range is 10 240 minutes in multiples of 10 10 20 30 etc 5 Click OK 6 Click Update Device to send the new settings to the meter and return to the main Communicator EXT screen 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 13 12 Flicker and Analysis 12 9 2 EN50160 1EC61000 4 30 Analysis NOTE A full week of logging is necessary before an EN50160 IEC61000 4 30 analysis can be created 1 From the Communicator EXT toolbar click Logs gt Retrieve Logs from Device s or click the Retrieve Logs icon You will see the screen shown below Select Log s to be Retrieved from Device lila BIET EL 252 F Unit 3 Retrieval Mode Partial Retrieval bd Log Type Historical Log 1 Historical Log 2 Digital Inputs Digital Outputs EN50160 IEC 61000 4 30 Available Available Available Cancel 2 Double click the No to the right of EN50160 IEC61000 4 30 3 You will see a pop up window displaying the message Updated Related Logs PQ and Historical Log 2 Click OK 4 The No changes to a Yes next to the Historical Log 2 Waveform PQ and EN50160 IEC61000 4 30 logs 5 C
29. capability without additional hardware This configuration of the meter is ideal for small remote applications aa 00 000 000 000 apas 1250 36 a 9 Originate Modem or internal to PC Figure 10 1 Meter Communication with Internal Modem Option 10 2 Hardware Connection Use RJ11 Standard Telephone Line to connect with the Nexus 1250 1252 meter Insert the RJ11 line into the RJ11 Port on the face of a Nexus meter with the Inter nal Modem Option The RJ11 connection is virtually unlimited since it utilizes a PSTN Public Switched Telephone Network Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 10 1 10 Meter with Internal Modem Option 10 3 Dial In Function The modem continuously monitors the telephone line to detect an incoming call When an incoming call is detected the modem waits a pre programmed number of rings and then answers the call The modem can be programmed to check passwords and lock out a user after unsuccessful attempts to connect When an incoming call is successfully connected the control of communication passes to the calling software program The modem respond to computer demands to down load data or perform other actions authorized by the meter s passwords 10 4 Dial Out Function The Dial Out Function
30. capable of logging Flicker values in an independent log When Flicker is on entries are made into the log in accordance with the times that associated values occur Pst Pst Max Pst Min Plt Plt Max Plt Min Start Reset and Stop times are all recorded All values can be downloaded to the Log Viewer where they are available for graphing or export to another program such as Excel All Flicker values are predefined and cannot be changed Refer to Chapter 8 of the Communicator EXT User Manual for additional instructions concerning the Flicker log 12 6 Polling through a Communication Port The Pinst Pst Pst Max Pst Min Plt Plt Max Plt Min values can be polled through the Communications Port Refer to the Nexus 1250 and 1252 meters Modbus and DNP Mapping manuals for register assignments and data definitions 12 7 Log Viewer 1 Open Log Viewer by selecting the Open Logs icon from Communicator EXT s Icon bar 2 Using the menus at the top of the screen select a meter time ranges and values to access 3 Click the Flicker icon The values and the associated time stamps when the values occurred are displayed in a grid box Use the buttons at the bottom of the screen to create a graph or export the data to another program e Graphed values include Pst and Plt Va Vb and Vc e Displayed values include Pst and Plt Max and Min for Va Vb and Vc NOTE Max and Min values are only displayed they cannot be graphed However M
31. control of communication is passed to the calling software program The modem responds to computer commands to download data or other actions authorized by the meter passwords Refer to the Communicator EXT User Manual for instructions on programming the modem 2 4 3 Dial Out Function The Dial Out Function INP2 is intended to allow the meter to automatically report certain conditions without user intervention The modem polls the meter to determine if any abnormal or reportable conditions exist The modem checks programmed meter conditions and programmed events set in Communicator EXT software to determine if a call should be placed If any of the monitored events exist the modem automatically initiates a call to a specified location to make a report or perform some other function For log full conditions the meter automatically downloads the log s that are nearing the full condition 2 5 Total Web Solutions The 10 100BaseT Ethernet Option INP200 is a fully customizable web server that uses XML to provide access to real time data via Internet Explorer EIG s name for this dynamic system is Total Web Solutions The system incorporates a highly programma ble network card with built in memory that is installed in the 100BaseT Option meters Each card can be programmed to perform an extensive array of monitoring functions The INP200 system is much faster than the 10BaseT Ethernet Option NOTE Nexus meters with the INP1O
32. e Set modem to display Result Codes The computer will use the result codes e Set modem to Verbal Result Codes The computer will use the verbal result codes e Set modem to use DTR Signal This is necessary for the computer to ensure connection with the originate modem e Set modem to enable Flow Control This is necessary to communicate with remote modem connected to the Nexus meter e Instruct modem to write the new settings to activate profile This places these settings into nonvolatile memory the setting will take effect after the modem powers up Modem Connected to the Nexus Meter the Remote Modem e Restore modem to factory settings This erases all previously programmed settings e Set modem to auto answer on n rings This sets the remote modem to answer the call after n rings e Set modem to ignore DIR Signal This is necessary for the Nexus meter to insure connection with originate modem e Set modem to disable Flow Control The Nexus meter s RS232 communication does not support this feature e Instruct modem to write the new settings to activate profile This places these settings into nonvolatile memory the setting will take effect after the modem powers up e When programming the remote modem with a terminal program make sure the baud rate of the terminal program matches the Nexus meter s baud rate 3 Electro Industries GaugeTech Doc E107706 5 16 The Leader In Power Monito
33. metering even though the actual ownership change occurs on the high voltage side The need for loss compensated metering may also exist when the ownership changes several miles along a transmission line where it is simply impractical to install meter ing equipment Ownership may change at the midway point of a transmission line where there are no substation facilities In this case power metering must again be compensated This condition is shown in Figure 7 2 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 Transformer Loss Compensation No LI Point of Ownership Change Figure 7 2 Joint Ownership Line Meeting Requiring Loss Compensation A single meter cannot measure the losses in a transformer or transmission line directly It can however include computational corrections to calculate the losses and add or subtract those losses to the power flow measured at the meter location This is the method used for loss compensation in the Nexus meter Refer to Appen dix B of the Communicator EXT User Manual for detailed explanation and instructions for using the Transformer Line Loss Compensation feature of the Nexus 1250 1252 meter The computational corrections used for transformer and transmission line loss com pensation are similar In both cases no load losses and full load losses are evaluated and a correction factor for each loss lev
34. send to and receive data from one another In most applications the network is either a serial type or a LAN type Nonvolatile Random Access Memory able to keep the stored values in memory even during the loss of circuit or control power High speed NVRAM is used in the Nexus meter to gather Cj Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 6 Glossary measured information and to insure that no information is lost Optical Port A port that facilitates infrared communication with a meter Using an ANSI C12 13 Type II magnetic optical communications coupler and an RS232 cable from the coupler to a PC the meter can be programmed with Communicator EXT software Packet A short fixed length section of data that is transmitted as a unit Example a serial string of 8 bit bytes Percent THD Percent Total Harmonic Distortion See THD Protocol A language that is spoken between two or more devices connected on a network PT Ratio Potential Transformer Ratio used to scale the value of the voltage to the primary side of an instrument transformer Also referred to as VT Ratio Pulse The closing and opening of the circuit of a two wire pulse system or the alternate closing and opening of one side and then the other of a three wire system which is equal to two pulses Q Readings Q is the quantity obtained by lagging the applied voltage to a wattm
35. the USB connection is being used You connect to the USB port using Communicator EXT software the same way you connect to a meter with the software Follow these instructions 1 Determine which port the PC s USB is using a On your PC click Start gt Settings gt Control Panel b Double click the System folder c Click the Hardware tab You will see the screen below System Properties we Syren Restore kasoma Updater Romte Compte Nane Husnu Advanced Device Manage The Dewce Manager bets af the hardeare devices notated on your Compute Use the Dece Manager to change the properties of ary dence Oevce Man Ey Ose Sigg ints you make suse that instaled Givers we Compatitte wath Windows Windows Update lets you set up brow airo conmect b Wirde Undate bor dever Drva Syeg Wro Update Haedreaee Potin Haswaa profiles provide a way tor pow to iet up and stone z Ihesi hurcdeewe contigs wnone l Hada Ponies Coe d Click the Device Manager button You will see a list of the computer s hardware devices Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays e Click the plus sign next to Ports COM amp LPT The COM ports are displayed Note the COM number for the USB Serial Port This is the number you will use to connect to the P40N through Communicator EXT See the figure below S amp S 8 N
36. the presence of higher order harmonic waveforms Traditionally the most common harmonics have been the low order odd frequencies such as the 3rd 5th 7th and 9th However newer new linear loads are introducing significant quantities of higher order harmonics Since much voltage monitoring and almost all current monitoring is performed using instrument transformers the higher order harmonics are often not visible Instrument transformers are designed to pass 60 Hz quantities with high accuracy These devices when designed for accuracy at low frequency do not pass high frequencies with high accuracy at frequencies above about 1200 Hz they pass almost no information So when instrument transformers are used they effectively filter out higher frequency harmonic distortion making it impossible to see However when monitors can be connected directly to the measured circuit such as direct connection to a 480 volt bus the user may often see higher order harmonic distortion An important rule in any harmonics study is to evaluate the type of equip ment and connections before drawing a conclusion Not being able to see harmonic distortion is not the same as not having harmonic distortion It is common in advanced meters to perform a function commonly referred to as waveform capture Waveform capture is the ability of a meter to capture a present Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solut
37. there is no data for more than 5 seconds Communication Lost appears on the bottom of the screen The following data is displayed when it is received e Amp Display P41N Amp A Amp B Amp C e Power Display P43N Watt VAR PF 3 Electro Industries GaugeTech Doc E107706 6 1 The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays The Nexus P40N LED external display has a USB port on the front for direct data downloads You can connect to the USB port with Communicator EXT to poll and configure the meter attached to the display To use the USB follow these instructions 1 Use the Nexus Series Product CD shipped with your meter to install the Communicator EXT software and the driver for the P40N USB port a Insert the CD into your PC s CD drive The screen shown below opens in your Browser ENTIRE EIG PRODUCT LINE EIG WEBSITE Soca meee www electroind com Nexus Series Electro industries GaugeTech The Leader in Power Monitoring and Smart Grid Solutions Electro Industries GaugeTech 1800 Shames Drive Westbury 11590 1 877 EIMETER 1 877 346 3837 Phone 616 334 0870 Fax 616 338 4741 www electroind com Requires Adobe Acrobat B b Click the Nexus Series Technical Documents button The following screen opens in your Browser Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Soluti
38. 000 0 COM INPUT 1 INPUT 2 INPUT 3 INPUT 4 INPUT 5 INPUT 6 INPUT 7 INPUT 8 O 1mA Analog Input Module COM INPUT 1 INPUT 2 INPUT 3 INPUT 4 INPUT 5 INPUT 6 INPUT 7 INPUT 8 Shield On Power Supply Max Power 12 VA Input Voltage 12 60v DC O 90 240v Ac Dc O Output Voltage 12V DC Electrolndustries GaugeTech www electroind com Control Power Reset Button Mounting Bracket I O Port Size and pin configuration vary Figure 9 5 PSIO Used with Multiple I O Modules NOTE As shown the PSIO must be to the right of O Modules when viewing the front label Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 External I O Modules 9 3 1 Steps for Attaching Multiple O Modules 1 Each I O module in a group must be assigned a unique address See the Communicator EXT User Manual for details on configuring and programming the I O Modules 2 Determine how many power sources such as the PSIO are needed for the number of modules in use See Section 5 6 2 for details 3 Starting with the left module and using a slotted screwdriver fasten the first I O Module to the left Mounting Bracket The left Mounting Bracket is the one with the PEM Fasten the internal screw tightly into the left Mounting Bracket 4 Next slide the fe
39. 00BaseT 5 10 5 6 Communication Ports on the Nexus I O Modules 5 10 5 6 1 RS485 Connection Nexus Meter to Nexus I O Modules 5 11 5 6 2 Steps to Determine Power Needed 5 11 5 7 Linking Multiple Nexus Meters in Series 5 13 5 8 Remote Communication Overview 5 14 5 8 1 Remote Communication RS232 5 14 5 8 2 Remote Communication RS485 5 15 5 8 3 Programming Modems for Remote Communication 5 15 5 8 3 1 Selected Modem Strings 5 17 5 9 High Speed Inputs Connection 5 17 5 10 IRIG B Connections 5 18 5 11 Time Synchronization Alternatives 5 20 I Using the External Displays 1 Overview 2 Nexus P40N P40N P41N and P43N LED External Displays 2 1 Connect Multiple Displays 2 2 Nexus P40N P40N Display Modes 3 Dynamic Readings Mode 4 Navigation Map of Dynamic Readings Mode 5 6 7 8 Nexus Information Mode Navigation Map of Nexus Information Mode Display Features Mode Navigation Map of Display Features Mode DAAADADAAARAADAG BPRPERPRPENAODHH ABRWNEFH 7 Transformer Loss Compensation 7 1 Introduction 7 2 Nexus 1250 1252 Meter s Transformer Loss Compensation 7 2 1 Loss Compensation in Three Element Installations 7 2 1 1 Three Element Loss Compensation Worksheet 8 Time of Use Function 8 1 Introduction 8 2 The Nexus Meter s TOU Calendar 8 3 TOU Prior Season and Month 8 4 8 5 Updating Retrieving and Replacing TOU Calendars Daylight Savings and Demand
40. 250 1252 meter If you use Port 1 set the selector switch beneath the port to RS485 e The link using RS485 is viable for up to 4000 feet 1219 meters e You must use an RS485 to RS232 converter such as EIG s Unicom 2500 See sections 5 3 2 and 5 3 3 e For information on connecting the Nexus 1250 1252 meter to a modem see sections 5 8 2 and 5 8 3 e Do not use the V V pins they supply power to the Nexus displays and I O modules 5 3 2 Connection to an RS485 Master Unicom or Modem Manager e To establish communication between a Nexus 1250 1252 meter and any RS485 master such as EIG s Unicom 2500 Modem Manager or other RS232 RS485 converter use a shielded twisted pair cable e Use an RS485 port Ports 1 4 on the Nexus meter If you use Port 1 set the selector switch beneath it to RS485 Connect the and terminals on the meter to the and terminals on the master Provide jumpers on the master linking its two terminals and two terminals RS485 communication is viable for up to 4000 feet 1219 meters e Connect the shield to the Ground G terminal on the Master The S terminal on the Nexus meter is used to reference the Nexus meter s port to the same potential as the source It is not an earth ground connection You must also connect the shield to earth ground at one point e Provide resistors at each end connected to the and lines RT is approxi mately 120 Ohms b
41. 3 7 Transformer Loss Compensation Loss Compensation is applied to 1 second per phase Watt VAR readings and because of that affects all subsequent readings based on 1 second per phase Watt VAR read ings This method results in loss compensation being applied to the following quanti ties e Total Power e Demands per Phase and Total Thermal Block Fixed Window Rolling Sliding Window and Predictive Window e Maximum and Minimum Demands e Energy Accumulations e KYZ Output of Energy Accumulations NOTE Loss Compensation is disabled when the meter is placed in Test Mode 7 2 Nexus 1250 1252 Meter s Transformer Loss Compensation The Nexus meter provides compensation for active and reactive power quantities by performing numerical calculations The factors used in these calculations are derived either e By clicking the TLC Calculator button on the Transformer Loss screen of the Device Profile to open the EIG Loss Compensation Calculator in Microsoft Excel e By figuring the values from the worksheet shown here and in Appendix B of the Communicator EXT User Manual Either way you enter the derived values into the Communicator EXT software through the Device Profile Transformer and Line Loss Compensation screen The Communicator EXT software allows you to enable Transformer Loss Compensa tion for Losses due to Copper and Iron individually or simultaneously Losses can either be added to or subtracted from mea
42. 5 8 I O Module Communication Ports Electro Industries GaugeTech Doc E107706 5 10 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring 5 6 1 RS485 Connection Nexus Meter to Nexus I O Modules e Six feet of RS485 cable harness is supplied Insert one end of the cable into Port 3 or Port 4 of the Nexus 1250 1252 meter e Insert the other end of the cable into the I O module s female RS485 side port see Figure 5 8 The connectors fit only one way into the ports e Use the male RS485 side port to attach another I O module The Nexus 1250 1252 meter can power up to four connected I O modules using 15 20V DC at 50 200mA Use the steps in Section 5 6 2 to determine if you must use a separate power source for example EIG s PSIO to supply added power to the group See Section 9 2 1 for information on the PSIO RS485 communication is viable for up to 4000 feet 1219 meters However if your cable length exceeds 200 feet use the remote power supply and 1 Connect the and terminals on the Nexus meter to the and terminals of the female RS485 port Connect the shield to the shield S terminal The S terminal on the Nexus meter is used to reference the meter s port to the same potential as the source It is not an earth ground connection You must also connect the shield to earth ground at one point 2 Provide termination resistors at each end connected to the a
43. 6 D2 Volts AC DC e Do not ground the unit through the negative of the DC supply Separate ground ing is required e Externally fuse the power supply with a 5 Amp 250V rated slow blow fuse EIG recommends that you fuse both the L and N connections for increased safety but if you are fusing only one connection fuse the L connection e Use at least 14 Gauge supply wire for the power supply and ground connections NOTE ON CORRECT METER FUNCTIONING The Nexus 1250 1252 meter has a Heartbeat LED located on the top right side of the meter face When the meter is functioning correctly the red LED pulse toggles on and off blinks 5 times per second If the meter is not functioning correctly the Heartbeat LED slows to one pulse per second 4 9 Wiring Diagrams Choose the diagram that best suits your application Diagrams appear on the follow ing pages If the connection diagram you need is not shown contact EIG for acustom Connection diagram NOTE If you purchased a G Option Nexus 1250 1252 meter for a 300 Volt secondary be sure to enable the option on the CT and PT screen of the Communicator EXT software s Device Profile see Chapter 3 of the Communicator EXT User Manual for instructions Do not use the G option with PTs It is intended for direct Voltage connection only 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 6 4 Electr
44. D and adjusts values for process 2 2 Calculates the percentage of Input Value NOTE The percentage value of the Input is stored in Input Value Registers Registers 04097 04104 The device will operate with the following default parameters Address 247 F7H Baud Rate 57600 Baud Transmit Delay Time 20 msec Normal Operation is prevented by a number of occurrences See Section 9 4 for details Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 External I O Modules 9 7 Digital Dry Contact Relay Output Form C Module Digital Dry Contact Relay Output Module Specifications Model Number 4RO1 4 matching relay outputs Contact Type Changeover SPDT Relay Type Mechanically latching Communication RS485 Modbus RTU Programmable Baud Rates 4800 9600 19200 38400 57600 Power Requirement 2 0W max 12 20VDC Operating Temperature 20 to 70 C 4 to 158 F Switching Voltage AC 250V DC 30V Switching Power 1250VA 150W Switching Current 5A Mechanical Life 5 x 107 switching operations Electrical Life 10 switching operations at rated current Factory Settings Modbus Address 156 Baud Rate 57600 Transmit Delay Time 0 Default Settings Reset Button Modbus Address 247 Baud Rate 57600 Transmit Delay Time 20msec
45. Default Gateway 0 0 0 0 Example 3 Click OK to return to the Device Profile screen Once the above parameters have been set Communicator EXT connects via the net work using a Device Address of 1 and the assigned IP Address when you follow these steps 1 Open Communicator EXT 2 Click the Connect icon in the icon tool bar The Connect screen opens 3 Click the Network button at the top of the screen Enter the following information Device Address 1 Host IP Address Network Port 502 Protocol Modbus TCP 4 Click the Connect button at the bottom of the screen Communicator EXT connects to the meter via the network To connect with other Nexus meters in either local or remote locations you must use the Ethernet Gateway as a Master and an RS485 connection to any port on the remote Nexus The Address of the remote Nexus meter must be something other than 1 1 is reserved for the meter connected to the network via RJ45 The link using RS485 is viable for up to 4000 feet 1219 meters Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 11 3 11 Meter with Internal Network Option This page intentionally left blank Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 11 4 12 Flicker and Analysis 12 12 1 12 2 Flicker and Analysis Overview Flicker is the se
46. If this string is present the modem plays the string to the host computer upon connec tion to identify the meter to the host software Refer to the Communicator EXT User Manual for programming details Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 10 3 10 Meter with Internal Modem Option This page intentionally left blank 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 10 4 11 Meter with Internal Network Option 11 Meter with Internal Network Option INP200 11 1 Hardware Overview The Nexus 1250 1252 meter with the Internal Network Option INP200 has all the components of the standard Nexus meter plus giving you the capability of connect ing to multiple PC s via Modbus TCP over the Ethernet and providing a DNP LAN WAN connection Additional hardware is not required to establish a connection from a net work to a Nexus meter with the Internal Network Option With the Internal Network Option the Nexus 1250 1252 provides an Ethernet Gate way allowing access to other Modbus RTU devices Additional connections can include a daisy chain of standard Nexus and Shark meters A daisy chain can 31 meters See Section 5 7 for repeater details Modbus RS485 Communication RJ45 Ethernet include up to 31 meters You can install repeaters if you need to connect more th
47. Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 11 12 Flicker and Analysis 12 9 EN50160 1EC61000 4 30 Power Quality Compliance Analysis Nexus 1252 meter with V 2 If your Nexus 1252 meter is equipped with V Switch key 2 you have access to the EN50160 IEC61000 4 30 PQ Compliance analysis function as well as to Flicker measurement 12 9 1 EN50160 I EC61000 4 30 Configuration 1 Select the Profile icon from Communicator EXT s Icon bar 2 From the Device Profile screen double click Power Quality and Alarm Set tings gt EN50160 IEC61000 4 30 Depending on your current setting you will see one of the following screens EN50160 IEC 61000 4 30 For EN50160 7 IEC 61000 4 30 legging to work property the PO leg and Historical Log 2 must be configured Doing so will overwrite the current PQ Limit and Historical Log 2 settings Press the Auto Conhgure button to automatically setup the PQ and Historical Log 2 settings to work with EN50160 IEC 61000 4 30 huoCordigne FVF changes per day Sync Connection Frequency Nominal Voltage fn Secor Short torm test bme PST Minutes Long term test time PLT Minutes EN50160 IEC 61000 4 30 To enable Historical Log 2 press the button below If Historical Log 2 is reenabled EN50160 7 IEC 61000 4 30 bogging wil no longer be conect Ena ieLog2 FVF changes per day Sync Connection Frequency Nominal Voltage Short term test tme P
48. Leader r Monitoring and Smart Grid Solutio 3 Hardware Installation 3 3 Mounting the Nexus External I O Modules Secure the mounting brackets to the I O using the screws supplied 440 pan head screws Next secure the brackets to a flat surface using a 8 screw with a lock washer If multiple I O modules are connected together as shown in Figure 3 5 secure a mounting bracket to both ends of the group One Nexus will supply power for a number of I O modules See Sections 5 6 2 to see if you need to use an additional power supply such as the EIG PSIO Connect multiple I O modules using the RS485 side ports Six feet of RS485 cable harness is supplied The cable harness brings power to the display from the Nexus meter See Chapter 5 for power supply and communication details 5 629 14 30cm 3X 1 301 3 305em 1 125 2 858cm ao wee Mounting Bracket 4 or y 090 229cm 4 Mounting Bracket 4 188 10 638cm JI ATASA JII Te 1 Figure 3 5 I O Modules Mounting Diagram Overhead View 3 Electro Industries GaugeTech l Doc E107706 3 25 The Leader In Power Monitoring and Smart Grid Solutions 3 Hardware Installation Mounting Brackets MBIO Female RS485 Side Port I O Port Size and Pin Configuration Vary Male RS485 Side Port Figure 3 6 I O Module Communication Ports and Mounting Brackets
49. Nexus 1250 1252 Power Meter and Power Quality Recorder fo 9 se O _ oO 2 Installation amp Operation Manual V 1 35 January 9 2013 The Leader In Power Monitoring and Smart Grid Solutions Electro Industries Gauge Tech 1800 Shames Drive Westbury NY 11590 Tel 516 334 0870 Fax 516 338 4741 Email sales electroind com This page intentionally left blank Nexus 1252 Meter Installation and Operation Manual Version 1 35 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 including photocopying record ing or information storage or retrieval systems or any future forms of duplication for any purpose other than the purchaser s use without the expressed written permission of Electro Industries GaugeTech 2013 Electro Industries GaugeTech Nexus is a registered trademark of Electro ndustries GaugeTech Communicator EXT is a trademark of Electro ndustries GaugeTech Windows is a registered trademark of Microsoft Corporation in the United States and or other countries Cj Electro Industries GaugeTech Doc E107706 l The Leader In Power Monitoring and Smart Grid Solutions This page intentionally left blank Electro Industries GaugeTech The Leader In Power Monitoring and Sma
50. Option do not support Total Web Solutions Ci Electro Industries GaugeTech Doc E107706 2 4 The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview 2 5 1 Hardware Overview The Nexus 1250 1252 with the 10 100BaseT Ethernet Option INP200 has all the components of the standard Nexus 1250 1252 plus the capability of connection to a network through an Ethernet LAN or through the Internet via Modbus TCP DNP3 LAN WAN 1252 only HTTP SMTP FTP and or DHCP The Internal Network Option of the Nexus meter is an extremely versatile communi cation tool The INP200 e Adheres to IEEE 802 3 Ethernet standard using TCP IP e Utilizes simple and inexpensive 10 100BaseT wiring and connections e Plugs right into your network using built in RJ 45 jack e Is programmable to any IP address subnet mask and gateway requirements e Communicates using the industry standard Modbus TCP and DNP3 LAN WAN over Ethernet 1252 only protocols 2 5 2 Hardware Connection Use Standard RJ 45 10 100BaseT cable to connect with the Nexus meter The R 45 line is inserted into the RJ 45 Port on the face of a Nexus meter with the INP200 Ethernet Option 2 5 3 Software Overview To make the software connection follow these steps 1 Using Port 1 or Port 4 RS485 connection connect a PC to the meter An RS232 RS485 Converter may be required Example Electro Industries Unicom 2500 2 Open Communicator EXT Software 3 Cl
51. Points over 3000 in the customizable DNP Point Map e Up to 16 Relays and 8 Resets can be controlled through DNP Level 2 e Report by Exception Processing DNP Events Deadbands can be set on a per point basis e Freeze Commands Freeze Freeze No Ack Freeze with Time Freeze with Time No Ack g Electro Industries GaugeTech Doc E107706 2 2 l The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview e Freeze with Time Commands enable the Nexus meter to have internal time driven Frozen and Frozen Event data When the Nexus meter receives the Time and Interval the data is created For complete details download the appropriate DNP User Manual from our website www electroind com 2 3 Flicker A Nexus 1252 with V 1 base configuration provides Flicker Evaluation in Instantaneous Short Term and Long Term Forms A Nexus 1252 meter with V Switch key 2 provides EN50160 EN61000 4 30 Power Quality Compliance See Chapter 12 for a detailed explanation of the Flicker and Power Quality Compliance functions 2 4 INP2 Internal Modem with Dial in Dial out Option The following sections describe the optional INP2 Internal Modem 2 4 1 Hardware Overview The INP2 Option for the Nexus 1250 1252 meter provides a direct connection to a standard telephone line No additional hardware is required to establish a communica tion connection between the meter and a remote computer The RJ 11 Jack
52. ST Minutes Long term test time PLT Minutes 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 12 12 Flicker and Analysis 3 The Nexus 1252 meter with V 2 can use Historical Log 2 to record the results of Flicker testing you will see the top screen if EN50160 IEC61000 4 30 logging has not been selected for the meter you will see the bottom screen if it has already been selected e To set up EN50160 1IEC61000 4 30 recording click Auto Configure Historical Log 2 will now be used for EN50160 IEC61000 4 30 logging only e If EN50160 IEC61000 4 30 recording is already active and you want to disable it click Enable Log 2 This will disable the EN50160 IEC61000 4 30 logging in Historical Log 2 You can then configure Historical Log 2 normally See Chapter 3 of the Communicator EXT User Manual for instructions NOTE It takes a week for the meter to collect all the data needed for the analysis 4 Make the following selections a FVF select the number of Fast Voltage Fluctuations that are acceptable per day b Sync Connection select YES for a system with a synchronous connection to another system NO if there is no such synchronous connection c Select your Frequency 50 Hz or 60Hz d Nominal Voltage in Secondary Enter the value for the Nominal voltage in Secondary that you want to use in the analysis for example 120 V for a 60 Hz frequency or 230
53. VOLTAGE POWER SUPPLY A B c N DEPENDENT ON EQUIPPED SUPPLY OPTION v LOAD Figure 4 3 4 Wire Wye 3 Element with 3 PTs and 4 CTs 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 9 4 Electrical Installation LINE ABCN j3 Vexus 1250 RTU Power Quality Revenue Meter A i i i In L N GND Vaux Veer Va Vb Ve SHORTING SWITCH OR TEST BLOCK CTs AUXILIARY VOLTAGE POWER SUPPLY A B c DEPENDENT ON EQUIPPED SUPPLY OPTION J LOAD Figure 4 4 4 Wire Wye 3 Element with 3 PTs and 3 CTs 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 Electrical Installation LINE ABC Cj Vexus 250 RTU Power Quality Revenue Meter L N GND Vaux Veer Va Vb Ve SHORTING SWITCH OR TEST BLOCK POWER SUPPLY DEPENDENT ON EQUIPPED SUPPLY OPTION Figure 4 5 3 Wire 2 Element Open Delta with 2 PTs and 3 CTs 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 11 4 Electrical Installation LINE AB c Cj Vexus 250 RTU Power Quality Revenue Meter A L N GND Vaux VreeF Va Vb Ve I j SHORTING SWITCH OR TEST BLOCK CTs POWER SUPPLY ABC DEPENDENT ON EQUIPPED SUPPLY OPTION LOAD Figure 4 6 3 Wire 2 Element Open Delta with 2 PTs and 2 CTs 3 Electro Industries GaugeT
54. Window Demand Predictive Window Demand enables the user to forecast average demand for future time intervals The Nexus uses the delta rate of change of a Rolling Window Demand interval to predict average demand for an approaching time period The user can set a relay or alarm to signal when the Predictive Window reaches a specific level thereby avoiding unacceptable demand levels The Nexus 1250 1252 calculates Predictive Window Demand using the following formula Example Using the previous settings of 3 five minute intervals and a new setting of 120 prediction factor the working of the Predictive Window Demand could be described as follows g Electro Industries GaugeTech Doc E107706 2 13 l The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview At 12 10 we have the average of the subintervals from 11 55 12 00 12 00 12 05 and 12 05 12 10 In five minutes 12 15 we will have an average of the subinter vals 12 00 12 05 and 12 05 12 10 which we know and 12 10 12 15 which we do not yet know As a guess we will use the last subinterval 12 05 12 10 as an approximation for the next subinterval 12 10 12 15 As a further refinement we will assume that the next subinterval might have a higher average 120 than the last subinterval As we progress into the subinterval for example up to 12 11 the Predictive Window Demand will be the average of the first two subintervals 12 00 12 05 12 05
55. Wiring e Avoid both star and tee connections see Figure 5 6 No more than two cables should be connected at any one point on an RS485 network whether the connec tions are for devices converters or terminal strips e Include all segments when calculating the total cable length ofa network If you are not using an RS485 repeater the maximum length for cable connecting all devices is 4000 feet 1219 meters e RT EXPLANATION Termination Resistors are generally used on both ends of longer length transmission lines The value of the Termination Resistors is determined by the electrical parameters of the cable Use RTs only on Master and Last Slave when connecting multiple meters in a Daisy Chain Slave device 1 Long stub results T connection that can cause i interference problem is sie andes Slave device 2 SH_ Master device Rr VF Cunnnnenae Twisted pair shielded SH cable Twisted pair shielded SH cable Earth Connection preferably at single location Twisted pair shielded SH cable Twisted pair shielded SH cable Slave device 1 Slave device 3 Twisted pair shielded SH cable Twisted pair shielded SH cable Figure 5 6 Incorrect T and Star Topologies Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring 5 3 1 RS485 Connection e Use any Port on the Nexus 1
56. alue for a given channel is completely ignored and no registers are modi fied If the difference is greater than half of the programmed Rollover Value for a given channel the write does not increment the Residual but does update the Last Value Overflow of the Residual is not prevented Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 13 9 External I O Modules 2 The second process occurs in the main loop and attempts to decrement the Resid ual by the Programmed Energy Pulse Value If the Residual is greater than the Pro grammed Energy Pulse Value and the Pending Pulses Value for that channel has not reached the maximum limit then Residual is decremented appropriately and the Pending Pulses is incremented by two signifying two more transitions and one more pulse 3 The third process runs from a timer which counts off pulse widths from the Pro grammable Minimum Pulse Width Values If there are Pulses Pending for a channel and the delay has passed then the Pulses Pending is decremented for that channel and the Output Relay is toggled Operation Indicator 0000H OK 1000H Problem Bit 1 1 EEPROM Failure Bit 2 1 Checksum for Communications Settings bad Bit 3 1 Checksum for Programmable Settings bad Bit 4 1 1 or more Communications Settings are invalid Bit 5 1 1 or more Programmable Settings are invalid Bit 6 1 1 or more Programmable Settings have been mod
57. an JEXUS 1250 lt Modbus TCP over Ethernet C co E e m m e elelelelelelele gog0ne3 Eeg 6060 olpeoodfooce loocccccce ooo aE nS Daisy Chain NEXUS 1250 Gas Wau et la b GHD ie jej l j ej j ej o LOGOGO A no A Network Connections a an y a EXUS 1250 cs 2 ele elelelele PA Sn Figure 11 1 Meter Communication with Network Option Daisy Chained Meters Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 11 1 11 Meter with Internal Network Option The Internal Network Option of the Nexus meter is an extremely versatile communi cations tool The Internal Network Option e Adheres to IEEE 802 3 Ethernet standard using TCP IP e Utilizes simple and inexpensive 10 100BaseT wiring and connections e Plugs into your network using built in RJ45 jack e Is programmable to any IP address subnet mask and gateway requirements e Communicates using the industry standard Modbus TCP and DNP LAN WAN protocols With the Internal Network Option the Nexus 1250 1252 meter s Port 2 becomes a gateway that allow
58. and Power Factor The real power and energy measurements discussed in the previous section relate to the quantities that are most used in electrical systems But it is often not sufficient to only measure real power and energy Reactive power is a critical component of the total power picture because almost all real life applications have an impact on reactive power Reactive power and power factor concepts relate to both load and generation applications However this discussion will be limited to analysis of reactive power and power factor as they relate to loads To simplify the discussion generation will not be considered Real power and energy is the component of power that is the combination of the voltage and the value of corresponding current that is directly in phase with the voltage However in actual practice the total current is almost never in phase with the voltage Since the current is not in phase with the voltage it is necessary to consider both the inpDhase component and the component that is at quadrature angularly rotated 90 or perpendicular to the voltage Figure 1 9 shows a single phase voltage and current and breaks the current into its in phase and quadrature components Figure 1 9 Voltage and Complex Current The voltage V and the total current I can be combined to calculate the apparent power or VA The voltage and the in phase current Ip are combined to produce the real power or watts The voltage and the
59. asurement 59 68 kWh The same process is applied to calculate the 15 minute demand value The demand value associated with the example load is 59 68 kWh hr or 59 68 kWd Note that the peak instantaneous value of power is 80 kW significantly more than the demand value Figure 1 8 shows another example of energy and demand In this case each bar represents the energy consumed in a 15 minute interval The energy use in each interval typically falls between 50 and 70 kWh However during two intervals the energy rises sharply and peaks at 100 kWh in interval number 7 This peak of usage will result in setting a high demand reading For each interval shown the demand value would be four times the indicated energy reading So interval 1 would have an associated demand of 240 kWh hr _ Interval 7 will have a demand value of 400 kWh hr In the data shown this is the peak demand value and would be the number that would set the demand charge on the utility bill 100 80 60 4 2 ie he mins kilowatt hours Oo oO oO Figure 1 8 Energy Use and Demand As can be seen from this example it is important to recognize the relationships between power energy and demand in order to control loads effectively or to monitor use correctly 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 11 1 Three Phase Power Measurement 1 3 Reactive Energy
60. ax and Min values are available for export 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 10 12 Flicker and Analysis 12 8 Performance Notes Pst and Plt average time are synchronized to the clock e g for a 10 minute average the times will occur at 0 10 20 etc The actual time of the first average can be less than the selected period to allow for initial clock synchronization If the wrong frequency is chosen e g 50Hz selection for a system operating at 60Hz Flicker will still operate but the computed values will not be valid Therefore you should select the frequency setting with care User settings are stored If Flicker is on and power is removed from the meter Flicker will still be on when power returns This can cause gaps in the logged data The Max and Min values are stored and are not lost if the unit is powered down Flicker meets the requirements of IEC 61000 4 15 and former IEC 868 Refer to those specifications for more details if needed Meters with the EN50160 option also meet the EN50160 conformance standards for Flicker Refer to chapters 16 and 17 in the Communicator EXT User Manual for additional information Operation is at 230V for 50Hz and 120V for 60Hz as per specification If the input voltage is different the system will normalize it to 230V or 120V for computational purposes Electro Industries GaugeTech The
61. cator EXT User Manual for details The cable required to terminate the voltage sense circuit should have an insulation rating greater than 600V AC and a current rating greater than 0 1 Amp Use a minimum of 14 AWG wire for all phase voltage and current connections The maximum installation torque for both the current input terminals and the voltage connections is 1 Newton Meter 4 3 Fusing the Voltage Connections For accuracy of the readings and for protection EIG requires using 0 25 Amp rated fuses on all voltage inputs as shown in the wiring diagrams see Section 4 9 The Nexus 1250 1252 meter can handle a maximum voltage of 150V phase to neu tral and 300V phase to phase Potential Transformers PTs are required for higher voltages with the standard rating With Option G the direct voltage input is extended to 300V phase to neutral and 600V phase to phase NOTE Option G is only intended for use with direct connections For PT connections use the standard 150 Volt version 4 4 Wiring the Monitored Inputs VRef The Voltage Reference connection references the monitor to ground or neutral 4 5 Wiring the Monitored Inputs VAux The Voltage Auxiliary connection is an auxiliary voltage input that can be used for any desired purpose such as monitoring neutral to ground voltage or monitoring two different lines on a switch The VAux Voltage rating is the same as the metering Volt age input connections 4 6 Wiring the Moni
62. change of about 2 degrees Celsius e Meets all ANSI C12 20 and IEC 62053 22 accuracy specifications e Adjusts for transformer and line losses using user defined compensation factors e Automatically logs time of use for up to eight programmable tariff registers e Counts pulses and aggregates different loads Nexus 1250 1252 Power Quality Monitoring e Records up to 512 samples per cycle on an event e Records sub cycle transients on voltage or current readings e Measures and records Harmonics to the 255th order Real Time Harmonics to the 128th order Cj Electro Industries GaugeTech Doc E107706 l The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview e Offers inputs for neutral to ground voltage measurements e Synchronizes with IRIG B or line frequency for clock synchronization e Measures Flicker 1252 only e Offers EN50160 EN61000 4 15 logging and analysis 1252 V 2 only see Section 2 11 Nexus 1250 1252 Memory Communication and Control e Up to 4 Megabytes NVRAM e 4 high speed Communication ports e Multiple protocols see section below on DNP V3 00 e Built in RTU functionality e Built in PLC functionality e High speed updates for Control 2 2 DNP V 3 00 Level 1 and 2 NOTE Nexus 1250 supports DNP V3 00 Level 1 Nexus 1252 supports DNP V3 00 Level 2 DNP Level 2 Features e Up to 136 measurement 64 Binary Inputs 8 Binary Counters 64 Analog Inputs can be mapped to DNP Static
63. d Solutions Doc E107706 12 2 12 Flicker and Analysis P 3s P 2 2 P 3 P 4 3 P 10s P 6 P 8 P 10 P 13 P 17 5 P 50s P 30 P 50 P 80 3 The 3 second memory time constant in the Flicker meter ensures that P 0 1 can not change abruptly and no smoothing is needed for this percentile Long Term Flicker Evaluation The 10 minute period on which the short term Flicker severity is based is suitable for short duty cycle disturbances For Flicker sources with long and variable duty cycles e g arc furnaces it is necessary to provide cri teria for long term assessment For this purpose the long term Plt is derived from the short term values over an appropriate period By definition this is 12 short term values of 10 minutes each over a period of 2 hours The following formula is used where Psti i 1 2 3 are consecutive readings of the short term severity Pst 12 2 1 Summary Flicker is changes in the illumination of light sources due to cyclical voltage variations Pinst is Instantaneous Flicker values in Perceptibility Units PU Pst is value based on 10 minute analysis Pit is value based on 12 Pst values Measurement Procedure 1 Original Signal with amplitude variations 2 Square demodulator 3 Weighted filter 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 3 12 Flicker and Analysis 4 Low pa
64. d to be invalid ITIC Curve An updated version of the CBEMA Curve that reflects further study into the performance of microprocessor devices The curve consists of a series of steps but still defines combinations of voltage magnitude and duration that will cause malfunction or damage Ke kWh per pulse i e the energy Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 5 Glossary kWh KYZ Output LCD LED Maximum Demand Modbus ASCII Modbus RTU Network NVRAM Kilowatt hours kW x demand interval in hours Output where the rate of changes between 1 and 0 reflects the magnitude of a metered quantity Liquid Crystal Display Light Emitting Diode The largest demand calculated during any interval over a billing period Alternate version of the Modbus protocol that utilizes a different data transfer format This version is not dependent upon strict timing as is the RTU version This is the best choice for telecommunications applications via modems The most common form of Modbus protocol Modbus RTU is an open protocol spoken by many field devices to enable devices from multiple vendors to communicate in a common language Data is transmitted in a timed binary format providing increased throughput and therefore increased performance A communications connection between two or more devices to enable those devices to
65. dary circuits can at times produce lethal voltages and currents Avoid contact with any current carrying surfaces Do not use the meter or any I O device for primary protection or in an energy limiting capacity The meter can only be used as secondary protec tion Do not use the meter for applications where failure of the meter may cause harm or death Do not use the meter for any application where there may be a risk of fire All meter terminals should be inaccessible after installation Do not apply more than the maximum voltage the meter or any attached device can withstand Refer to meter and or device labels and to the Specifications for all devices before applying voltages Do not HIPOT Dielectric test any Outputs Inputs or Com munications terminals EIG recommends the use of Fuses for voltage leads and power supply and shorting blocks to prevent hazardous voltage conditions or damage to CTs if the meter needs to be removed from service CT grounding is optional The current inputs are only to be connected to external current transformers 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 Electrical Installation To comply with UL standards the meter case must be connected to a reliable protective earth available within the installation area For this connection use minimum 14 AWG wire crimped to a ring terminal 3 with a dedicated tool Fasten the r
66. device has been corrupted during transmission If the calculated value does not match the value in the request packet the Slave ignores the request A Current Transformer Ratio is used to scale the value of the current from a secondary value up to the primary side of an instrument transformer The sum of the previous billing period maximum demand readings at the time of billing period reset The maximum demand for the most recent billing period is added to the previously Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 3 Glossary accumulated total of the maximum demands Demand The average value of power or a similar quantity over a specified period of time Demand Interval A specified time over which demand is calculated Display User configurable visual indication of data in a meter DNP 3 0 A robust non proprietary protocol based on existing open standards DNP 3 0 is used to operate between various systems in electric and other utility industries and SCADA networks EEPROM Nonvolatile memory Electrically Erasable Programmable Read Only Memory that retains its data during a power outage without need for a battery Also refers to meter s FLASH memory Energy Register Programmable record that monitors any energy quantity Example Watthours VARhours VAhours Ethernet A type of LAN network connection that connects two or more dev
67. dication Time of Use Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 10 Glossary Uncompensated Power V2T Threshold Voltage Imbalance Voltage Quality Event VT Ratio Voltage Vab Voltage Van VA Watt and VAR readings not adjusted by Transformer Loss Compensation Data will stop accumulating when voltage falls below programmed level The ratio of the voltage on a phase to the average voltage on all phases An instance of abnormal voltage on a phase The events the meter tracks include sags swells interruptions and imbalances The Voltage Transformer Ratio is used to scale the value of the voltage to the primary side of an instrument transformer Also referred to as PT Ratio Vab Vbc Vca are all Phase to Phase voltage measurements These voltages are measured between the three phase voltage inputs to the meter Van Vbn Vcn are all Phase to Neutral voltages applied to the monitor These voltages are measured between the phase voltage inputs and Vn input to the meter Technologically these voltages can be measured even when the meter is in a Delta configuration and there is no connec tion to the Vn input However in this configura tion these voltages have limited meaning and are typically not reported Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions D
68. e Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays 6 5 Nexus Information Mode Use the Mode button to access the Nexus Information mode from other modes Use the Up Down arrows to navigate from group to group within this mode See Section 6 6 for a Navigation map of the Nexus Information Mode Group 1 Device Time Meter Time Group 2 Communication Settings Use the Left Right arrows to access the follow ing readings in order e Communication Settings Port 1 Baud Addr Protocol e Communication Settings Port 2 Baud Addr Protocol e Communication Settings Port 3 Baud Addr Protocol e Communication Settings Port 4 Baud Addr Protocol Group 3 PT CT Ratios Use the Left Right arrows to access the following readings in order e PT Ratio e CT Ratio Group 4 External Display Units Primary Secondary Select either Primary or Secondary units for the External Display using the Communi cator EXT software see the Communicator EXT User Manual e When Primary is selected the Display shows all readings in Primary units based on the user programmed PT and CT Ratios e When Secondary is selected the Display shows all readings in Secondary units Group 5 Firmware Versions and Serial Numbers Use the Left Right arrows to access the following readings in order a 3 Electro Industries GaugeTech Doc E107706 6 12 The Leader In Power Monitoring and Smart Grid Solutions
69. e phase Wye Winding The three voltages are separated by 120 electrically Under balanced load conditions the currents are also separated by 120 However unbalanced loads and other conditions can cause the currents to depart from the ideal 120 separation Three phase voltages and currents are usually represented with a phasor diagram A phasor diagram for the typical connected voltages and currents is shown in Figure 1 2 Figure 1 2 Phasor Diagram Showing Three phase Voltages and Currents Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 2 1 Three Phase Power Measurement The phasor diagram shows the 120 angular separation between the phase voltages The phase to phase voltage in a balanced three phase wye system is 1 732 times the phase to neutral voltage The center point of the wye is tied together and is typically grounded Table 1 1 shows the common voltages used in the United States for wye connected systems Phase to Ground Voltage Phase to Phase Voltage 120 volts 208 volts 277 volts 480 volts 2 400 volts 4 160 volts 7 200 volts 12 470 volts 7 620 volts 13 200 volts Table 1 Common Phase Voltages on Wye Services Usually a wye connected service will have four wires three wires for the phases and one for the neutral The three phase wires connect to the three phases as shown in Figure 1 1 The neutral wire is
70. e will become the new start time and the settings of the new calendar will be used Reset the current accumulations if you replace a calendar in use A reset clears only the current accumulation registers This causes the current accumulations to use the present date as the start and accumulate to the next new end date which will be taken from the new calendar Once stored prior accumulations are always available and cannot be reset See Chapter 3 of the Communicator EXT User Manual for instructions on resetting TOU accumulations At the end of a defined period current accumulations are stored the registers are cleared and accumulations for the next period begin When the year boundary is a 3 Electro Industries GaugeTech Doc E107706 B69 The Leader In Power Monitoring and Smart Grid Solutions 8 Time of Use Function crossed the second calendar if present is used To retain continuity you have up to one year to replace the old calendar with one for the following year 8 5 Daylight Savings and Demand To enable Daylight Savings Time for the meter from the Device Profile menu click General Settings gt Time Settings In the Time Settings screen click Auto DST which sets Daylight Savings Time automatically for the United States only You can also select User Defined and enter the desired dates for Daylight Savings Time See Chapter 3 of the Communicator EXT User Manual for instructions To set Demand interva
71. eTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 15 4 Electrical Installation This page intentionally left blank Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 5 Communication Wiring 5 Communication Wiring This chapter provides wiring information for the Nexus 1250 1252 meter s communication options 5 1 Communication Overview RS232 communication is used to connect a single Nexus 1250 1252 meter with another device such as a computer RTU or PLC The link is viable for a distance of up to 50 feet 15 2 meters and is available only through the meter s Port 1 You must set the selector switch beneath the port to RS232 RS485 communication allows multiple Nexus meters to communicate with another device at a local or remote site The I O modules and the Nexus displays use RS485 to communicate with the Nexus meter All RS485 links are viable for a distance of up to 4000 feet 1220 meters Ports 1 through 4 on the Nexus 1250 1252 meter are two wire RS485 connections operating up to 115200 baud To use Port 1 for RS485 set the selector switch to RS485 the switch is located under the port RJ11 Telephone Line allows a Nexus 1250 1252 meter with the Internal Modem Option INP2 to communicate with a PC No other hardware is necessary for this easy to use connection For more details see Chapter 10 g U
72. ear for the clock GPS does not supply the year 3 Connect the terminal of the Nexus meter to the terminal of the signal generating device connect the terminal of the Nexus meter to the terminal of the signal generating device Troubleshooting Tip The most ommon source of problems is a reversal of the two wires If you have a problem try reversing the wires IRIG B Port IRIG B Time Signal Generating Device Figure 5 12 IRIG B Communication The Leader In Power Monitoring and Smart Grid Solutions Cj Electro Industries GaugeTech Doc E107706 5 19 5 Communication Wiring NOTE Please make sure that the selected clock can drive the amount of wired loads 5 11 Time Synchronization Alternatives See the Communicator EXT User Manual for details IRIG B e All Nexus 1250 1252 meters are equipped to use IRIG B for time synchroniza tion e If IRIG B is connected this form of time synchronization takes precedence over the internal clock If the GPS Signal is lost the internal clock takes over time keeping at the precise moment the signal is lost Line Frequency Clock Synchronization e All Nexus meters are equipped with Line Frequency Clock Synchronization which may be enabled or disabled for use instead of IRIG B If Line Frequency Clock Synchronization is enabled and power is lost the internal clock takes over at the precise moment power is lost Internal Clock Crystal
73. ech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 Electrical Installation LINE ABC Cj Vexus i250 RTU Power Quality Revenue Meter RAA I SHORTING SWITCH OR TEST BLOCK EARTH POWER SUPPLY DEPENDENT ON EQUIPPED SUPPLY OPTION A B C LOAD Figure 4 7 3 Wire 2 Element Delta Direct Voltage with 3 CTs 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 13 4 Electrical Installation LINE ABCN j Vexus i250 RTU Power Quality Revenue Meter A Hi I 1 i j L N GND Vaux Veer Va Vb Ve SHORTING SWITCH OR TEST BLOCK CTs Vaux AUXILIARY VOLTAGE POWER SUPPLY A B c N DEPENDENT ON EQUIPPED SUPPLY OPTION z LOAD Figure 4 8 3 Phase 4 Wire 2 5 Element with 2 PTs and 3 CTs 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 14 4 Electrical Installation LINE ABCN Cj Vexus i250 RTU Power Quality Revenue Meter A L N GND Vaux Veer Va Vb Ve i 1 tit i i i I 1 r 1 1 SHORTING SWITCH OR TEST BLOCK m O 3 e oo 11 2 EARTH lt HI Q CTs bolo 3 HI Q i LO AUXILIARY VOLTAGE POWER SUPPLY DEPENDENT ON EQUIPPED SUPPLY OPTION ABCN I l LOAD Figure 4 9 4 Wire 3 Element Grounded Delta with 4 CTs G Option 3 Electro Industries Gaug
74. el is calculated However the calculation of the correction factors that must be programmed into the meter differ for the two dif ferent applications For this reason the two methodologies will be treated separately in this chapter In the Nexus meter Loss Compensation is a technique that computationally accounts for active and reactive power losses The meter calculations are based on the formulas below These equations describe the amount of active Watts and reac tive VARs power lost due to both iron and copper effects reflected to the secondary of the instrument transformers Total Secondary Watt Loss Measured Voltage Cal point Voltage 2 x LWFE Measured Current Cal Point Current 2 x LWCU x Full scale Secondary VA 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 2 7 Transformer Loss Compensation Total Secondary VAR Loss Measured Voltage Cal point Voltage 4 x LVFE Measured Current Cal Point Current 2 x LVCU x Full scale Secondary VA The Values for LWFE LWCU LVFE and LVCU are derived from the trans former and meter information as demonstrated in the following sections The calculated loss compensation values are added to or subtracted from the mea sured Watts and VARs The selection of adding or subtracting losses is made through the meter s profile when programming the meter see the following section for instructions
75. enabled by the INP2 Option allows the meter to automatically report certain conditions without direct user oversight The modem normally polls the meter to determine if any abnormal or reportable conditions exist such as those in the following list If such conditions are found the modem checks meter conditions and events which have been programmed through Communicator EXT to determine if a call should be placed e Are any meter set point limits exceeded e Has the status of the High Speed Inputs changed e Has a waveform been recorded e Has a power quality event been recorded e Has a control output changed e Is either history log approaching a full condition e Is the event log approaching a full condition e Is any other log approaching a full condition e Has the Modem Password failed e Has communication with the Nexus meter failed If any of the monitored events exist the modem automatically initiates a call to a specified location to make a report or perform some other function For log full condi 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 10 2 10 Meter with Internal Modem Option tions the meter automatically downloads the log s that are nearing the full state The modem can be programmed to call two different numbers to make the required reports Primary and Backup The modem can be programmed with an ASCII string for identification purposes
76. er In Power Monitoring and Smart Grid Solutions Doc E107706 4 4 4 Electrical Installation 4 7 Isolating a CT Connection Reversal For a Wye System you may either e Check the current phase angle reading on the meter s external display see Chapter 6 If it is negative reverse the CTs e Go to the Phasors screen of the Communicator EXT software see Chapter 3 of the Communicator EXT User Manual for instructions Note the phase relationship between the current and voltage they should be in phase with each other For a Delta System e Go to the Phasors screen of the Communicator EXT software program see Chapter 3 of the Communicator EXT User Manual for instructions The current should be 30 degrees off the phase to phase voltage 4 8 Instrument Power Connections The Nexus 1250 1252 meter requires a separate power source To use AC power 1 Connect the line supply wire to the L terminal 2 Connect the neutral supply wire to the N terminal on the meter To use DC power 1 Connect the positive supply wire to the L terminal 2 Connect the negative ground supply wire to the N terminal on the meter Power supply options and corresponding suffixes are listed in the table shown on the next page 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 5 4 Electrical Installation Control Option Power Suffix 18 60 Volts D DC 90 27
77. ered scalable Analog Transducer I nputs e 8Al1 8 Analog Inputs 0 1mA scalable and bidirectional e 8AI2 8 Analog Inputs 0 20mA scalable e 8AI3 8 Analog Inputs 0 5V DC scalable e 8Al4 8 Analog Inputs 0 10V DC scalable Electro Industries GaugeTech Doc E107706 2 15 l The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview Digital Dry Contact Relay Outputs e 4RO1 4 Relay Outputs 10 Amps 125V AC 30V DC Form C Digital Solid State Pulse Outputs e 4PO1 4 Solid State Pulse Outputs Form A KYZ pulses Digital I nputs e 8DI1 8 Digital status inputs Wet Dry Auto Detect up to 300V AC DC Other I O Accessories e PSIO 12V power supply for I O modules and external displays e MBIO Bracket for surface mounting I O modules to any enclosure Electra Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview 2 9 Nexus 1250 1252 Meter Specifications UL Measurement Category Category Ill Rated Altitude 2 000 Meters Maximum Specification Nexus meter Control Power Requirement Option D 24VDC 20 to 48 VDC 20 Option D2 120V AC DC 20 to 230VAC 20 Connection Screws Torque 6 to 9 in Ib max or 0 68 to 1 Nm max Input Voltage Range 150 Volts Phase to Neutral 300V Phase to Phase Standard for use with PTs 300 Volts Phase to Neutral 600V Phase to Phase Option G
78. erived from a specified number of sub intervals each of a specified time For Ci Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 8 Glossary example the average is calculated over a 15 minute interval by calculating the sum of the average of three consecutive 5 minute intervals This demand calculation methodology has been adopted by several utilities to prevent customer manipulation of kW demand by simply spreading peak demand across two intervals RS232 A type of serial network connection that connects two devices to enable communication between the devices An RS232 connection connects only two points Distance between devices is typically limited to fairly short runs Current standards recommend a maximum of 50 feet but some users have had success with runs up to 100 feet Communications speed is typically in the range of 1200 bits per second to 57 600 bits per second RS232 connection can be accomplished using Port 1 of the Nexus 1250 1252 meter RS485 A type of serial network connection that connects two or more devices to enable communication between the devices An RS485 connection allows multi drop communication from one to many points Distance between devices is typically limited to around 2 000 to 3 000 wire feet Communications speed is typically in the range of 120 bits per second to 115 000 bits per second Sag A voltage quality event during w
79. es GaugeTech Doc E107706 8 1 The Leader In Power Monitoring and Smart Grid Solutions 8 Time of Use Function If the year ends and there is no new calendar TOU accumulations stop The last accumulation for the year ends on 12 31 23 59 59 If a calendar is present for the following year TOU accumulations continue until the next monthly bill date or next start of season is reached Accumulation can span into the following year 8 3 TOU Prior Season and Month The Nexus 1250 1252 meter stores accumulations for the prior season and the prior month When the end of a billing period is reached the current season or month becomes stored as the prior The registers are then cleared and accumulations resume using the next set of TOU schedules and register assignments from the stored calendar Prior and current accumulations to date are always available 8 4 Updating Retrieving and Replacing TOU Calendars Communicator EXT software retrieves TOU calendars from the Nexus meter or from the computer s hard drive for review and edit Up to a maximum of twenty yearly calendars can be stored in the Nexus meter at any given time You may retrieve them one at a time a new calendar can be stored while a current calendar is in use Accumulations do not stop during calendar updates If a calendar is replaced while in use the accumulations for the current period will continue until the set end date At that point the current tim
80. es take into account both energy consumption and peak demand when billing customers 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 1252 supports the following most popular conventions for averaging demand and peak demand Block Window Demand Rolling Window Demand Thermal Demand and Predictive Window Demand You can program and access all conventions concurrently with the Communicator EXT software see the Communicator EXT User Manual Block Fixed Window Demand This convention records the average arithmetic mean demand for consecutive time intervals usually 15 minutes Example A typical setting of 15 minutes produces an average value every 15 minutes at 12 00 12 15 12 30 etc for power reading over the previous fifteen minute interval 11 45 12 00 12 00 12 15 12 15 12 30 etc Rolling Sliding Window Demand Rolling Window Demand functions like multiple overlapping Block Window Demands The programmable settings provided are the number and length of demand subinter vals At every subinterval an average arithmetic mean of power readings over the subinterval is internally calculated This new subinterval average is then averaged Electro Industries GaugeTech Doc E107706 2 12 l The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview arithmetic mean with as many previous subin
81. esigned manufactured tested and calibrated at our facil ity in Westbury New York Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions This page intentionally left blank Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 vi Table of Contents Table of Contents Customer Service and Support ii Product Warranty ii Limitation of Warranty ii Statement of Calibration iii Disclaimer iii About Electro Industries GaugeTech iv 1 1 Three Phase Power Measurement 1 1 Three Phase System Configurations 1 1 1 Wye Connection 1 2 Delta Connection 1 3 Blondell s Theorem and Three Phase Measurement 2 Power Energy and Demand 3 Reactive Energy and Power Factor 4 H 5 armonic Distortion Power Quality Seal sell pel etl oe el a Li FPRPRFODArRH 1 1 1 l 1 I NAN Li 2 Meter Overview 2 1 The Nexus System 2 2 DNP V 3 00 Level 1 and 2 2 3 Flicker 2 4 INP2 Internal Modem with Dial in Dial out Option 2 4 1 Hardware Overview 2 4 2 Dial In Function 2 4 3 Dial Out Function 2 5 Total Web Solutions 2 5 1 Hardware Overview 2 5 2 Hardware Connection 2 5 3 Software Overview 2 5 4 Network Settings 2 6 Measurements and Calculations NNNNNNNNNNNNNNNNNN N FPREFPRFPRFPODUUUBRARARWWWNPH 2 7 Demand Integrators 12 2 8 Nexus External I O Modules
82. eter by 60 degrees Values are displayed on the Uncompensated Power and Q Readings screen 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 7 Glossary Quadrant Programmable Values and Factors on the Nexus meter Register Register Rollover Reset Rolling Window Average Power Watt and VAR flow is typically represented using an X Y coordinate system The four corners of the X Y plane are referred to as quadrants Most power applications label the right hand corner as the first quadrant and number the remaining quadrants in a counter clockwise rotation Follow ing are the positions of the quadrants ist upper right 2nd upper left 3rd lower left and 4th lower right Power flow is generally positive in quadrants 1 and 4 VAR flow is positive in quadrants 1 and 2 The most common load conditions are Quadrant 1 power flow positive VAR flow positive inductive load lagging or positive power factor Quadrant 2 power flow negative VAR flow positive capacitive load leading or negative power factor An entry or record that stores a small amount of data A point at which a Register reaches its maximum value and rolls over to zero Logs are cleared or new or default values are sent to counters or timers The Rolling Sliding Window Average is the average power calculated over a user set time interval that is d
83. etwork adapters E PCMCIA and Flash memory devices GY Ports COM amp LPT Wf Communications Port COM F USB Serial Port com6 lt MR Processors amp SCSI and RAID controllers imp 4 SM Driver Sound video and game controllers 2 Open Communicator EXT software and click the Connect icon in the Icon bar See the screen shown below Connect 9 Serial Port Device Address Baud Rate Available Ports 9 All Ports Port COMB Protocol Modbus RTU Flow Control P Echo Mode o Eero 3 Click the Serial Port button if it s not already selected 4 Set the Baud Rate to 9600 It uses 9600 because it shares an existing Com port for displayed readings 5 Click the Available Ports button and select the USB COM Port number from the drop down list 6 Protocol should be Modbus RTU 7 Flow Control should be None 3 Electro Industries GaugeTech Doc E107706 Bas The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays 8 Echo Mode should be No Echo 9 Click Connect The software connects to the meter through the P40N Refer to the Communicator EXT User s Manual for programming instructions Click Help gt Contents from the Communicator EXT Title Bar to view the manual online 6 2 1 Connect Multiple Displays One cable housing two wire RS485 and two wire power wires plus shield is used to connect the display
84. fferent load may have a constant power requirement of 4 000 watts If the load were served for one hour it would absorb four kWh If the load were served for 15 minutes it would absorb of that total or one kWh Figure 1 7 shows a graph of power and the resulting energy that would be transmitted as a result of the illustrated power values For this illustration it is assumed that the power level is held constant for each minute when a measurement is taken Each bar 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 8 1 Three Phase Power Measurement in the graph will represent the power load for the one minute increment of time In real life the power value moves almost constantly The data from Figure 1 7 is reproduced in Table 2 to illustrate the calculation of energy Since the time increment of the measurement is one minute and since we specified that the load is constant over that minute we can convert the power reading to an equivalent consumed energy reading by multiplying the power reading times 1 60 converting the time base from minutes to hours 80 70 60 50 oO z 40 30 20 10 0 T T T T T T T T T T T T T T 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Time minutes Figure 1 7 Power Use over Time 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 9 1 Three Phase Powe
85. g the Communicator EXT software see the Modbus Communicating I O Modules User Manual 9 5 Analog Transducer Signal Output Modules Analog Transducer Signal Output Module Specifications Model Numbers 1mAON4 4 channel analog output 0 1mA 1mAONB8 8 channel analog output 0 1mMA 20mAON4 4 channel analog output 4 20mA 20mAONB 8 channel analog output 4 20mA Accuracy 0 1 of Full Scale Scaling Programmable Communication RS485 Modbus RTU Programmable Baud Rates 4800 9600 19200 38400 57600 Power Requirement 15 20VDC 50 200mA 1250 1252 supports up to two modules Operating Temperature 20 to 70 C 4 to 158 F Maximum Load Impedance O 1imA 10k Ohms 4 20mA 500 Ohms Factory Settings Modbus Address 1mMAON4 128 1mAONS8 128 20mAON4 132 2ZOMAONB 132 Baud Rate 57600 Transmit Delay Time 0 Default Settings Reset Button Modbus Address 247 Baud Rate 57600 Transmit Delay Time 20msec 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 External I O Modules 9 5 1 Overview The Analog Transducer Signal Output Modules O 1mA or 4 20mA are available in either a 4 or 8 channel configuration Maximum registers per request read or write is 17 registers The Nexus 1250 1252 meter supplies power for up to two connected Analog Output modules See Section 9 2 fo
86. hich the RMS voltage is lower than normal for a period of time typically from 1 2 cycle to 1 minute 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 9 Glossary Secondary Rated Serial Port Swell TDD THD Time Stamp TOU Any Register or pulse output that does not use any CT or PT VT Ratio The type of port used to directly interface with a device using the RS232 standard A voltage quality event during which the RMS voltage is higher than normal for a period of time typically from 1 2 cycle to 1 minute The Total Demand Distortion of the current waveform The ratio of the root sum square value of the harmonic current to the maximum demand load current See equation below NOTE The TDD displayed in the Harmonics screen is calculated by Communicator EXT software using the Max Average Demand ope J 242 12 x100 I L Total Harmonic Distortion is the combined effect of all harmonics measured in a voltage or current The THD number is expressed as a percent of the fundamental For example a 3 THD indicates that the magnitude of all harmonic distortion measured equals 3 of the magnitude of the fundamental 60Hz quantity The THD displayed is calculated by your Nexus meter A stored representation of the time of an event Time Stamp can include year month day hour minute second and Daylight Savings Time in
87. ial port of the Nexus 1250 1252 meter s Port 1 Program this port for Modbus ASCII See Chapter 3 of the Communicator EXT User Manual for details e You must use a Null Modem or Null Cable between the Nexus meter and the remote modem when using RS232 A Null Modem enables two DCE devices to communicate The figure below details how a null modem reconfigures the RS232 pins Pins at Null Modem Male End 1 2 3 4 5 6 7 1 2 3 8 20 7 4 5 6 Pins at Female Modem Male End Figure 5 10 Standard Null Modem Configuration 3 Electro Industries GaugeTech Doc E107706 5 14 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring NOTE Connecting the Nexus meter to a modem via RS485 protocol with EIG s Modem Manager converter eliminates the need for a Null Modem see Section 5 8 2 e The remote modem must be programmed for auto answer and set at a fixed baud rate of 9600 with no Flow Control See Section 5 8 3 and the Communicator EXT User Manual for further details 5 8 2 Remote Communication RS485 Use any Port on the Nexus 1250 1252 meter If you use Port 1 set the selector switch beneath the port to RS485 The link using RS485 is viable for up to 4000 feet 1219 meters Use Communicator EXT software to set the port s baud rate to 9600 and enable Modbus ASCII protocol See Chapter 3 of the Communicator EXT User Manual for instructions Remember Modbus RTU will not function properly
88. ical Installation Figure Description 4 2 4 Wire Wye 3 Element Direct Voltage with 4 CTs 4 3 4 Wire Wye 3 Element with 3 PTs and 4 CTs 4 4 4 Wire Wye 3 Element with 3 PTs and 3 CTs 4 5 3 Wire 2 Element Open Delta with 2 PTs and 3 CTs 4 6 3 Wire 2 Element Open Delta with 2 PTs and 2 CTs 4 7 3 Wire 2 Element Delta Direct Voltage with 3 CTs 4 8 3 Phase 4 Wire Wye 2 5 Element with 2 PTs and 3 CTs 4 9 4 Wire 3 Element Grounded Delta with 4 CTs G Option Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 Electrical Installation LINE ABCN j5 Vexusi250 RTU Power Quality Revenue Meter la Hi Ib Hi Ic Hi In Hi L N GND Vaux Veer Va Vb Ve Lo i 4 i SHORTING SWITCH OR TEST BLOCK in wl 1 13 Ic H E HI CTs lb wolo 5 HI Q b LO Vref Vaux AUXILIARY VOLTAGE POWER SUPPLY DEPENDENT ON EQUIPPED SUPPLY OPTION ABCN LOAD Figure 4 2 4 Wire Wye 3 Element Direct Voltage with 4 CTs 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 8 4 Electrical Installation LINE ABCN Cj Vexus i250 RTU Power Quality Revenue Meter A L N GND Vaux Veer Va Vb Ve TEST BLOCK HI o m l2 TT HI o Ic Lo o 1 B SHORTING SWITCH OR HI Q CTs Ib wlio 3 HI Q o a olo B FUSES PTs AUXILIARY
89. ices on a common commun ications backbone An Ethernet LAN consists of at least one hub device the network backbone with multiple devices connected to it in a star configu ration The most common versions of Ethernet in use are 10BaseT and 100BaseT as defined in IEEE 802 3 standards However several other versions of Ethernet are also available Flicker Flicker is the sensation that is experienced by the human visual system when it is subjected to 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 4 Glossary changes occurring in the illumination intensity of light sources IEC 61000 4 15 and former IEC 868 describe the methods used to determine Flicker severity Harmonics Measuring values of the fundamental current and voltage and percent of the fundamental Heartbeat Pulse Energy indicator on the face of the Nexus 1250 1252 meter pulses are generated per the programmed Ke value I2T Threshold Data will not accumulate until current reaches programmed level Integer Any of the natural numbers the negatives of those numbers or zero Internal Modem An optional modem within the meter s enclosure that connects to the RJ11 telephone connector Invalid Register In the Nexus meter s Modbus Map there are gaps between Registers For example the next Register after 08320 is 34817 Any unmapped Register stores no information and is sai
90. ick the Quick Connect or the Connection Manager icon in the Icon tool bar In the Connect window that opens click the Serial Port button Make sure the connection data such as Address matches the meter and then click Connect g Electro Industries GaugeTech Doc E107706 2 5 l The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview 2 5 4 Network Settings Configure the Network Settings using the following steps refer to the Communicator EXT User Manual for more details 1 From Communicator EXT s Main screen click Profile to open the Device Profile screen 2 From the Device Profile screen double click on the Communications Ports line then double click on any of the ports The Communications Settings screen opens 3 If you are going to use DHCP click the Advanced Settings button and follow these steps a Click the DHCP tab at the top of the Advanced Settings screen b Click Enable DHCP automatically enters the IP Address and some or all of the Interface Settings c Click OK at the bottom of the screen to return to the Communication Setting screen You may have to manually enter DNS Email Gateway Setting and or a unique computer name Consult your Network Administrator if you are not sure of the correct information to enter d Click OK 4 If you are not using DHCP enter the following information in the Network Settings section of the Communication Settings screen consult
91. ified Bit 7 1 Forced Default by Reset Value Bit 15 1 Normal Operation of the device is disabled Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 External I O Modules 9 9 Digital Status Input Module Digital Status Input Module Specifications Model Number 8DI1 Communication RS485 Modbus RTU Programmable Baud Rates 4800 9600 19200 38400 57600 Power Requirement 15 20VDC 50 200mA 1250 1252 supports up to four modules Operating Temperature 20 to 70 C 4 to 158 F Voltage Rating Up to 300VDC Detection Wet Dry Auto detect Memory 256 Byte I2C EEPROM for storage of programmable settings and non volatile memory Factory Settings Modbus Address 164 Baud Rate 57600 Transmit Delay Time 0 Default Settings Reset Button Modbus Address 247 Baud Rate 57600 Transmit Delay Time 20msec 9 9 1 Overview The Digital Status Input Module is used either for additional status detect or for accu mulating pulses from external equipment such as power meters water meters etc The Nexus 1250 1252 meter supplies power for up to 4 connected Digital Status Input modules See Section 9 2 for power and communication details Refer to Section 5 6 2 to determine if you must use an additional power source such as EIG s PSIO Cj Electro Ind
92. ing terminal 3 to the lower left slot of the meter case with minimum 6 metal screw 1 and star washer 2 as is shown in Figure 4 1 The UL Classification of the meter is Measurement Category III Pollution Degree 2 Figure 4 1 Meter Case s Earth Ground Connection NOTE IF THE EQUIPMENT IS USED IN A MANNER NOT SPECIFIED BY THE MANUFACTURER THE PROTECTION PROVIDED BY THE EQUIPMENT MAY BE IMPAIRED NOTE THERE IS NO REQUIRED PREVENTIVE MAINTENANCE OR INSPECTION NECESSARY FOR SAFETY HOWEVER ANY REPAIR OR MAINTENANCE SHOULD BE PERFORMED BY THE FACTORY DISCONNECT DEVICE The following part is considered the equipment disconnect device A SWITCH OR CIRCUIT BREAKER SHALL BE INCLUDED IN THE END USE EQUIPMENT OR BUILDING INSTALLATION THE SWITCH SHALL BE IN CLOSE PROXIMITY TO THE EQUIPMENT AND WITHIN EASY REACH OF THE OPERATOR THE SWITCH SHALL BE MARKED AS THE DISCONNECTING DEVICE FOR THE EQUIPMENT Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 2 4 Electrical Installation 4 2 Wiring the Monitored Inputs and Voltages Select a wiring diagram from Section 4 9 that best suits your application Wire the Nexus 1250 1252 meter exactly as shown For proper operation the voltage con nection must be maintained and must correspond to the correct terminal Program the CT and PT Ratios in the Device Profile section of the Communicator EXT software see the Communi
93. ins as an A Press the Up arrow to increment the character from A Z and then from 0 9 Press the Down arrow to decrement the character from A to 9 0 and then from Z A 3 Press Set to enter each character in the password 4 When the entire password is shown on the Display screen press Enter 5 Once the password is entered correctly press Enter again to reset the Max Min values Group 2 Reset Energy Press Enter to reset the Energy readings NOTE If the Password Protection feature has been enabled through Communicator EXT software you will need to enter a password to reset the Energy readings Follow steps 1 4 above Then press Enter again to reset energy Group 3 Display Baud Rate Address Group 4 Display Communication Protocol Group 7 Lamp Test a 3 Electro Industries GaugeTech Doc E107706 6 14 The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays Press Enter to conduct an LED test Group 8 Display Scroll ON OFF Press Enter to turn the scroll feature on or off When the scroll feature is on the P40N external display scrolls 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 E107706 The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays 6 8 Navigation Map of Display Features Mode
94. ion Wiring e You can use ANY port to connect a Nexus display or RS485 Master The I O modules use Port 3 or Port 4 Nexus P40N P41N and P43N displays are shipped pre programmed to use Port 3 see Section 5 3 4 for details 5 2 RS232 Connection Port 1 e Use Port 1 for RS232 communication Set the selector switch beneath the port to RS232 e Insert one end of an RS232 extension cable into the Nexus 1250 1252 meter s 9 pin female serial port Insert the opposite end into a port on the computer e The RS232 standard limits the cable length to 50 feet 15 2 meters e The RS232 Port is configured as Data Communications Equipment DCE RS232 Port RS485 Port Pin 2 Transmit Pin 3 Receive V S Pin 5 Ground Pins 5 432 1 98 7 6 Figure 5 4 RS232 RS485 Port Detail 5 3 RS485 Communication RS485 communication allows multiple devices to communicate on a bus The Nexus 1250 1252 meter s Ports 1 to 4 are RS485 terminals viable for a distance of up to 4000 feet 1219 meters Port 1 can be switched between RS232 and RS485 The following figure shows wiring detail of a 2 wire RS485 port Electro Industries GaugeTech Doc E107706 5 4 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring Nexus Meter From other RS485 device anita Connect anann N e tt e to S 7 e Shield SH to Shield SH RS485 connection Figure 5 5
95. ions Doc E107706 9 External I O Modules 9 8 Digital Solid State Pulse Output KYZ Module Digital Solid State Pulse Output Module Specifications Model Number 4PO1 Communication RS485 Modbus RTU Programmable Baud Rates 4800 9600 19200 38400 57600 Power Requirement 15 20VDC 50 200mA 1250 1252 supports up to four modules Operating Temperature 20 to 70 C 4 to 158 F Voltage Rating Up to 300VDC Commands Accepted Read and Write with at least 4 registers of data per command Memory 256 Byte IC EEPROM for storage of programmable set tings and non volatile memory Factory Settings Modbus Address 160 Baud Rate 57600 Transmit Delay Time 0 Default Settings Reset Button Modbus Address 247 Baud Rate 57600 Transmit Delay Time 20msec 9 8 1 Overview The KYZ Pulse Output Modules have 4 KYZ Pulse Outputs and accept Read and Write Commands with at least 4 registers of data per command Digital Solid State Pulse Output KYZ Modules are user programmed to reflect VAR hours Watt hours or VA hours See the Modbus Communicating I O Modules User Manual for details on programming the module The Nexus 1250 1252 meter supplies power for up to 4connected KYZ Pulse Output modules See Section 9 2 for power and communication details Refer to Section 5 6 2 to determine if you must use an additional power
96. ions Doc E107706 1 16 1 Three Phase Power Measurement picture of the voltage or current waveform for viewing and harmonic analysis Typi cally a waveform capture will be one or two cycles in duration and can be viewed as the actual waveform as a spectral view of the harmonic content or a tabular view showing the magnitude and phase shift of each harmonic value Data collected with waveform capture is typically not saved to memory Waveform capture is a real time data collection event Waveform capture should not be confused with waveform recording that is used to record multiple cycles of all voltage and current waveforms in response to a transient condition 1 5 Power Quality Power quality can mean several different things The terms power quality and power quality problem have been applied to all types of conditions A simple definition of power quality problem is any voltage current or frequency deviation that results in mis operation or failure of customer equipment or systems The causes of power quality problems vary widely and may originate in the customer equipment in an adjacent customer facility or with the utility Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 Three Phase Power Measurement In his book Power Quality Primer Barry Kennedy provided information on different types of power quality problems Some of that information is summa
97. ire three voltage coils and three current coils a three element meter Similar figures and conclusions could be reached for other circuit configurations involving Delta connected loads 1 2 Power Energy and Demand It is quite common to exchange power energy and demand without differentiating between the three Because this practice can lead to confusion the differences between these three measurements will be discussed Power is an instantaneous reading The power reading provided by a meter is the present flow of watts Power is measured immediately just like current In many digital meters the power value is actually measured and calculated over a one second interval because it takes some amount of time to calculate the RMS values of voltage and current But this time interval is kept small to preserve the instantaneous nature of power Energy is always based on some time increment it is the integration of power over a defined time increment Energy is an important value because almost all electric bills are based in part on the amount of energy used Typically electrical energy is measured in units of kilowatt hours kWh A kilowatt hour represents a constant load of one thousand watts one kilowatt for one hour Stated another way if the power delivered instantaneous watts is measured as 1 000 watts and the load was served for a one hour time interval then the load would have absorbed one kilowatt hour of energy A di
98. is on the face of the meter A standard telephone RJ 11 plug can connect the meter to a stan dard PSTN Public Switched Telephone Network The modem operates at up to 56k baud It supports both incoming calls from a remote computer and automatic dial out calls when a defined event must be auto matically reported With the device configured with the INP2 Option the meter has dial in capability and provides remote access to other Modbus based serial devices via the meter s RS485 Gateway over your phone line The meter recognizes and responds to a Modbus Address of 1 With any other address the command passes through the gateway and become a virtual connection between the remote Modbus master and any Modbus slave connected to the RS485 Gateway The modem continuously monitors the telephone line to detect an incoming call When an incoming call is detected the modem will wait a user set number of rings and answer the call Electra Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview 2 4 2 Dial In Function The modem can be programmed to check for a password on an incoming call If the correct password is not provided the modem hangs up on the incoming call If several unsuccessful incoming call attempts are received in a set time period the modem locks out future incoming calls for a user set number of hours When an incoming call is successfully connected the
99. is theorem states If energy is supplied to any system of conductors through N wires the total power in the system is given by the algebraic sum of the readings of N wattmeters so arranged that each of the N wires contains one current coil the corresponding potential coil being connected between that wire and some common point If this common point is on one of the N wires the measurement may be made by the use of N 1 Wattmeters The theorem may be stated more simply in modern language In a system of N conductors N 1 meter elements will measure the power or energy taken provided that all the potential coils have a common tie to the conductor in which there is no current coil Three phase power measurement is accomplished by measuring the three individual phases and adding them together to obtain the total three phase value In older analog meters this measurement was accomplished using up to three separate elements Each element combined the single phase voltage and current to produce a torque on the meter disk All three elements were arranged around the disk so that the disk was subjected to the combined torque of the three elements As a result the disk would turn at a higher speed and register power supplied by each of the three wires According to Blondell s Theorem it was possible to reduce the number of elements under certain conditions For example a three phase three wire delta system could be correctly measured with two e
100. lements two potential coils and two current coils if the potential coils were connected between the three phases with one phase in common In a three phase four wire wye system it is necessary to use three elements Three voltage coils are connected between the three phases and the common neutral conductor A current coil is required in each of the three phases In modern digital meters Blondell s Theorem is still applied to obtain proper metering The difference in modern meters is that the digital meter measures each 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 6 1 Three Phase Power Measurement phase voltage and current and calculates the single phase power for each phase The meter then sums the three phase powers to a single three phase reading Some digital meters calculate the individual phase power values one phase at a time This means the meter samples the voltage and current on one phase and calculates a power value Then it samples the second phase and calculates the power for the second phase Finally it samples the third phase and calculates that phase power After sampling all three phases the meter combines the three readings to create the equivalent three phase power value Using mathematical averaging techniques this method can derive a quite accurate measurement of three phase power More advanced meters actually sample all three phases of
101. lick Start to begin retrieving the logs Communicator EXT retrieves the selected logs and automatically creates a database for you Pop ups confirm the retrieval and conversion 6 The Log Viewer screen appears See Chapter 8 of the Communicator EXT User Manual for additional information on using the Log Viewer Cj Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 14 12 Flicker and Analysis 7 Click the EN50160 IEC61000 4 30 button A screen shows the data points required Click YES 8 A list of all weeks collected for this meter is displayed Information provided includes e Start End Time of Week e Device Name e Nominal Frequency Voltage e Pass Fail Value for each component 9 Select a week from those displayed 10 Click the IEC 61000 4 30 button at the bottom of the screen A full analysis is generated 11 The EN50160 IEC61000 4 30 HTML Viewer screen is displayed See Chapter 16 in the Communicator EXT User Manual for detailed instructions on using the EN50160 IEC61000 4 30 HTML Viewer screen Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 15 12 Flicker and Analysis This page intentionally left blank Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 16 13 Substation Rack Mount Assembly 13 Substation 19 inch
102. ls from the Device Profile menu click Revenue and Energy Settings gt Demand Integration I ntervals and set the desired intervals See Chap ter 3 of the Communicator EXT User Manual for instructions To set Cumulative Demand Type from the Device Profile menu click Revenue and Energy Settings gt Cumulative Demand Type and select Block or Rolling Window Aver age See Chapter 3 of the Communicator EXT User Manual for instructions Cj Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 8 Time of Use Function This page intentionally left blank Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 External I O Modules 9 External I O Modules 9 1 Hardware Overview All Nexus External I O modules have the following components Female RS485 Side Port use to connect to another module s male RS485 side port e Male RS485 Side Port use to connect to the Nexus 1250 1252 Meter s Port 3 or 4 or to another module s female RS485 side port e I O Port used for functions specific to the type of module size and pin configura tion vary depending on type of module e Reset Button Press and hold for three seconds to reset the module s baud rate to 57600 and its address to 247 for 30 seconds e LEDs when flashing signal that the module is functioning e Mounting Brackets MBIO used to secure one o
103. m or by calling 516 334 0870 USA You will be asked for the following information a Serial number s of the meter you are upgrading b Desired V Switch upgrade c Credit card or Purchase Order number 2 EIG will issue you the V Switch upgrade key To enable the key follow these steps a Open Communicator EXT software b Power up your Nexus meter c Connect to the meter via Communicator EXT See Chapter 3 of the Communicator EXT User Manual for detailed instructions you can open the manual online by clicking Help gt Contents from the Communicator EXT Main screen d Click Tools gt Change V Switch from the Title Bar of the Main screen A screen opens requesting the encrypted key e Enter the upgrade key provided by EIG f Click OK The V Switch key is enabled and the meter is reset NOTE The Nexus 1250 meter does not have a V Switch key upgrade Ci Electro Industries GaugeTech Doc E107706 2 19 The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview This page intentionally left blank Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 3 Hardware Installation 3 Hardware Installation This chapter provides installation information for the Nexus 1250 1252 meter and its optional modules and displays 3 1 Mounting the Nexus 1250 1252 Meter The Nexus 1250 1252 Meter is designed to moun
104. male RS485 port into the male RS485 side port to connect the next I O module to the left module Fasten together enough to grab but do not tighten yet 5 One by one combine the modules together 6 If you require an additional power supply attach a PSIO power supply to the right of the group of I O Modules it is supplying with power NOTE The PB1 can also be used for a Low Wltage Power Supply It must be mounted separately 7 Once you have combined all the I O modules together for the group fasten tightly This final tightening will lock the whole group together as a unit 8 Attach the right Mounting Bracket to the right side of the group using small phillips head screws provided 9 Mount the group of modules on a secure flat surface This procedure will insure that all modules stay securely connected 9 4 Factory Settings and Reset Button Factory Settings All Nexus I O Modules are shipped with a preset address and a baud rate of 57600 See following sections for I O Module addresses 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 5 9 External I O Modules Reset Button If there is a communication problem or if you are unsure of a module s address and baud rate press and hold the RESET button for 3 seconds the module will reset to a default address of 247 at 57600 baud rate for 30 seconds This enables you to interrogate the I O usin
105. n important WARNING or CAUTION in the operating instructions Please see Chapter 4 for important safety information regarding installation and hookup of the meter The following safety symbols may be used on the meter itself This symbol alerts you to the presence of high voltage which can cause dangerous electrical shock This symbol indicates the field wiring terminal that must be connected to earth ground before operating the meter which protects against electrical shock in case of a fault condition Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions About Electro I ndustries GaugeTech EIG Founded in 1975 by engineer and inventor Dr Samuel Kagan Electro ndustries GaugeTech changed the face of power monitoring forever with its first breakthrough innovation an affordable easy to use AC power meter Thirty years since its founding Electro ndustries GaugeTech the leader in power monitoring and control continues to revolutionize the industry with the highest qual ity cutting edge power monitoring and control technology on the market today An ISO 9001 2000 certified company EIG sets the industry standard for advanced power quality and reporting revenue metering and substation data acquisition and control EIG products can be found on site at mainly all of today s leading manufacturers industrial giants and utilities EIG products are primarily d
106. nd lines RT is approximately 120 Ohms See RT EXPLANATION in Section 5 3 5 6 2 Steps to Determine Power Needed Available power for all ports of the Nexus 1250 1252 meter is 12 VA 1 Refer to the tables on the next two pages to determine the VA Ratings for I O modules and displays 2 Add together the VA Ratings for all I O modules and displays in use 3 Compare available power to power needed to determine if you must use an additional power source NOTE EIG recommends the PSIO 12V power source if the I O module VA rating exceeds the Nexus specification See Section 9 2 1 for information and usage instructions 3 Electro Industries GaugeTech Doc E107706 511 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring 1 O Module Factory Settings and VA Ratings Model Module Address VA Rating ImAON4 0 imA 4 Analog 128 2 7VA Outputs 1mAON8 0 imA 8 Analog 128 3 2VA Outputs 20mAON4 4 20mA 4 Analog 132 5 0VA Outputs 20mAON8 4 20mA 8 Analog 132 8 5VA Outputs 8AI1 0 1imA 8 Analog 136 2 3VA Inputs 8AI2 0 20mA 8 Analog 140 2 3VA Inputs 8AI3 0 5VDC 8 Analog 144 2 3VA Inputs 8AI4 0 10VDC 8 Analog 148 2 3VA Inputs 4RO1 4 Latching Relay 156 2 7VA Outputs 4PO1 4 KYZ Pulse Outputs 160 2 7VA 8DI1 8 Status Inputs 164 1 0VA Wet Dry As the table above shows all I O modules are shipped pre programmed with a baud
107. ng For three phase transformers these values will typically be the three phase rating and the phase to phase votage All of the test measurements are based on these two numbers Part of the process of calculating the loss compensation percentages is converting thetransformer loss values based on the transformer ratings to the base used by the meter Correct calculation of loss compensation also requires knowledge of the meter instal lation In order to calculate the loss compensation settings you will need the following information regarding the meter and the installation e Number of meter elements 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 Transformer Loss Compensation e Potential Transformer Ratio PTR e Current Transformer Ratio CTR e Meter Base Voltage e Meter Base Current This section is limited to application of Nexus meters to three element metering installations As a result we know that e Number of metering elements 3 e Meter Base Voltage 120 Volts e Meter Base Current 5 Amps 7 2 1 1 Three Element Loss Compensation Worksheet Company Station Name Date Trf Bank No Trf Manf Trf Serial No Calculation by Transformer Data from Transformer Manufacturer s Test Sheet Winding Voltage MVA Connection HV High A Y XV Low A Y YV Tertiary A Y 3 Elec
108. nsation that is experienced by the human visual system when it is subjected to changes occurring in the illumination intensity of light sources The primary effects of Flicker are headaches irritability and sometimes epileptic seizures IEC 61000 4 15 and former IEC 868 describe the methods used to determine Flicker severity This phenomenon is strictly related to the sensitivity and the reaction of indi viduals It can only be studied on a statistical basis by setting up suitable experiments among people The Nexus 1250 1252 meter with V 1 base configuration offers Flicker monitoring and analysis The Nexus 1252 meter with V 2 has EN50160 IEC61000 4 30 Power Quality Compliance analysis for Flicker and other power quality measurements Refer to the V Switch key information in Chapter 2 Refer to Chapters 16 EN50160 IEC61000 4 30 Power Quality Compliance Analysis and 17 EN50160 IEC61000 4 15 Flicker of the Communicator EXT User Manual for additional information Theory of Operation Flicker can be caused by voltage variations that are in turn caused by variable loads such as arc furnaces laser printers and microwave ovens In order to model the eye brain change which is a complex physiological process the signal from the power network has to be processed while conforming with Figure 12 1 shown on page 12 4 e Block 1 consists of scaling circuitry and an automatic gain control function that nor malizes input voltages
109. nt 1 Phase kVA Self Cooled Rating 100 100 kVA No Load Loss VAR kVAR SQRT No Load Loss kVA 2 No Load Loss kW 2 SQRT 2 2 SQRT SQRT Full Load Loss Watts kW 1 Phase Kw Load Loss Full Load Loss VA kVA Impedance 1 Phase kVA Self Cooled Rating 100 100 kVA Full Load Loss VAR kVAR SQRT Full Load Loss kVA 2 Full Load Loss kW 2 SQRT 2 2 SQRT SQRT a Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 Transformer Loss Compensation Normalize Losses to Meter Base Quantity Value M T Factor M T Factor Exp M T Factor Value at Trf Value w Exp at Base Meter Base No Load V 2 Loss kW No Load V M4 Loss kVAR Load Loss 1 2 kW Load Loss 1 2 kVAR Enter Value at Transformer Base for each quantity from calculations above Enter Meter Trf Factor value from Base Conversion Factor calculations above Calculate M T Factor with Exponent by raising the M T Factor to the power indicated in the Exp or Exponent column Calculate the Value at Meter Base by multiplying the M T Factor w Exp times the Value at Trf Base Loss Watts Percentage Values Meter Base kVA 600 PT Multiplier CT Multiplier 1000 600 Z 1000
110. oc E107706 GL 11 Glossary Voltage Vaux This is the fourth voltage input measured from between the Vaux and Vref inputs This input can be scaled to any value However the actual input voltage to the meter should be of the same magnitude as the voltages applied to the Va Vb and Vc terminals 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 12
111. ons Doc E107706 6 2 6 Using the External Displays NEXUS 1250 1250 NEXUS 1262 1272 r SOCKET METER SWITCHBOARD OPERATION MANUAL QUICKSTART QUICKSTART NEXUS 1500 INSTALLATION AND amp OPERATION MANUAL ates Fm COMMUNICATOR EXT 3 0 USB DRIVER Nexus Series E 6 Q 3 re rs 2 Electro industries Gauge Tech The Leader in Power Monitoring and Smart Grid Solutions Electro Industries GaugeTech 1800 Shames Drive Westbury 11590 1 877 EIMETER 1 877 346 3837 Phone 616 334 0870 Fax 616 338 4741 www electroind com Requires Adobe Acrobat amp c To install Communicator EXT 3 0 software and the driver for the P40N i Click on the Communicator EXT 3 0 button and click Run The software is installed ii Click on the USB Driver button click Run The P40N driver is installed 2 Connect the USB cable from your PC to the port using a USA A Male to USB B Male cable attach the USB A connector to the PC and attach the USB B connector to the P40N USB port See Figure 6 1 Figure 6 1 USB B Male Connector and P40N USB Port Cj Electro Industries GaugeTech Doc E107706 63 The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays 3 Once the USB cable is connected to the P40N the display clears and the message USB in Use scrolls at the bottom of the display Additionally the USB LED icon lights up when
112. ons IRIG B is a standard time code format that synchronizes event time stamping to within 1 millisecond An IRIG B signal generating device connected to the GPS satellite system synchronizes Nexus 1250 1252 meters located at different geographic locations Nexus meters use an un modulated signal from a satellite controlled clock such as Arbiter 1093B For details on installation refer to the Users Manual for the satellite controlled clock in use Below are installation steps and tips that will help you Connection Connect the terminal of the Nexus meter to the terminal of the signal gen erating device connect the terminal of the Nexus meter to the terminal of the signal generating device a 3 Electro Industries GaugeTech Doc E107706 5 18 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring Installation Set Time Settings for the meter being installed 1 From the Communicator EXT Device Profile menu a Click General Settings gt Time Settings gt one of the Time Settings lines to open the Time Settings screen b Set the Time Zone and Daylight Savings Select AutoDST or Enable and set dates c Click Update Device Profile to save the new settings See Chapter 3 of the Communicator EXT User s Manual for details 2 Before connection check that the date on the meter clock is correct or within 2 Months of the actual date This provides the right y
113. our screw holes for attaching to the panel 1 Align the rack assembly s screw holes with the holes in the panel see Figure 13 2 2 Insert two screws on each side of the rack assembly into the panel to secure it 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 13 2 13 Substation Rack Mount Assembly 19 00 48 26cm 18 02 45 77 m 49 1 24em A H 4 00 10 16cm Figure 13 2 Rack Assembly Dimensions 13 6 Wiring The voltage and current signals from the potential and current transformers should be connected to the Test switch see Figure 13 4 There are positions for voltage and current phases A B and C Neutral voltage and DC Power supply The Test switches are labeled for easy wiring Please follow the Nexus 1252 meter wiring diagrams concerning proper connections see Section 4 9 13 7 Ordering nformation The rack assembly ordering code is 4RU3DSP It is placed at the end of the Nexus 1252 meter order for example 1252 A 120 D 60 V1 X X 4RU3DSP which translates to a Nexus 1252 meter with Advanced memory 120 Input Voltage option D Power Supply option 60Hz V Switch key 1 no expansion port no Reve nue Seal and in the rack assembly Ci Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 13 3
114. phase For Wye x a b c VAR JVA W Active Power Watts Total N number of samples For Wye W W W W Electra Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview For Delta N YD Caw i Lacy T Vece e la t 1 N W Reactive Power VAR Total N number of samples For Wye VAR VAR VAR VAR For Delta 2 2 N N 2 2 vao Law 5 Vko AO VAR Vp us y us a Crus eT rus T N Apparent Power VA Total For Wye VA VA VA VA For Delta VA JW VAR g Electro Industries GaugeTech Doc E107706 2 10 l The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview Power Factor PF For Wye x a b c T For Delta x T Phase Angles X a b c Z cos PF Total Harmonic Distortion THD For Wye X V3 V Vor ia ip ic For Delta x ia ip ig Vab Vbe Vea 127 X RMS THD RMS K Factor x ig ip ic 127 2 gt he RMS hel KFactor r gt MS h 1 Cj Electra Industries GaugeTech Doc E107706 l The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview Watt hour Wh N number of samples N W Wh X 2 2 3600 t 1 sec hr VAR hour VARh N number of samples N VAR 1 3600 VARh sec hr 2 7 Demand Integrators Power utiliti
115. quadrature current Ix are combined to calculate the reactive power The quadrature current may be lagging the voltage as shown in Figure 1 9 or it may lead the voltage When the quadrature current lags the voltage the load is requiring both real power watts and reactive power VARs When the quadrature current Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 12 1 Three Phase Power Measurement leads the voltage the load is requiring real power watts but is delivering reactive power VARs back into the system that is VARs are flowing in the opposite direction of the real power flow Reactive power VARs is required in all power systems Any equipment that uses magnetization to operate requires VARs Usually the magnitude of VARs is relatively low compared to the real power quantities Utilities have an interest in maintaining VAR requirements at the customer to a low value in order to maximize the return on plant invested to deliver energy When lines are carrying VARs they cannot carry as many watts So keeping the VAR content low allows a line to carry its full capacity of watts In order to encourage customers to keep VAR requirements low some utilities impose a penalty if the VAR content of the load rises above a specified value A common method of measuring reactive power requirements is power factor Power factor can be defined in two different ways The mo
116. quency This modeling is performed by mathematically disassembling the distorted waveform into a collection of higher frequency waveforms These higher frequency waveforms are referred to as harmonics Figure 1 12 shows the content of the harmonic frequencies that make up the distortion portion of the waveform in Figure 1 11 500 Time o Amps 3rd harmonic 5th harmonic 500 7th harmonic Total fundamental Figure 1 12 Waveforms of the Harmonics 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 15 1 Three Phase Power Measurement The waveforms shown in Figure 1 12 are not smoothed but do provide an indication of the impact of combining multiple harmonic frequencies together When harmonics are present it is important to remember that these quantities are operating at higher frequencies Therefore they do not always respond in the same manner as 60 Hz values Inductive and capacitive impedance are present in all power systems We are accus tomed to thinking about these impedances as they perform at 60 Hz However these impedances are subject to frequency variation X joL and Xc 1 joC At 60 Hz 377 but at 300 Hz 5th harmonic 1 885 As frequency changes impedance changes and system impedance characteristics that are normal at 60 Hz may behave entirely differently in
117. r Measurement ime Power energy Amat minute kw KWh kWh 1 30 0 50 0 50 2 50 0 83 1 33 3 40 0 67 2 00 4 55 0 92 2 92 5 60 1 00 3 92 6 60 1 00 4 92 7 70 1 17 6 09 8 70 147 76 9 60 1 00 8 26 10 70 1 17 9 43 11 80 L33 10 76 12 50 0 83 12 42 13 50 0 83 12 42 14 70 ET 13 59 15 80 L33 14 92 Table 1 2 Power and Energy Relationship over Time As in Table 1 2 the accumulated energy for the power load profile of Figure 1 7 is 14 92 kWh Demand is also a time based value The demand is the average rate of energy use over time The actual label for demand is kilowatt hours hour but this is normally reduced to kilowatts This makes it easy to confuse demand with power but demand is not an instantaneous value To calculate demand it is necessary to accumulate the energy readings as illustrated in Figure 1 7 and adjust the energy reading to an hourly value that constitutes the demand In the example the accumulated energy is 14 92 kWh But this measurement was made over a 15 minute interval To convert the reading to a demand value it must be normalized to a 60 minute interval If the pattern were repeated for an additional three 15 minute intervals the total energy would be four times the measured value or Cj Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 Three Phase Power Me
118. r more modules to a flat surface Mounting Brackets MBIO Female RS485 Side Port I O Port Size and Pin Male RS485 Configuration Vary Side Port Figure 9 1 I O Module Components 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 1 9 External I O Modules 9 1 1 Port Overview All Electro Industries I O Modules have ports through which they interface with other devices The port configurations are variations of the four types shown below Four Analog Outputs Eight Analog Outputs 0 1mA and 4 20mA 0 1mA and 4 20mA 1mA 0 1mA Analog Output Analog Input le Module ie 0 2 0 O RESET J O Eight Analog I nputs Four Relay Outputs 0 1mA 0 20mA 0 5Vdc or Four KYZ Pulse Outputs 0 10Vdc or Eight Status I nputs 1mA Analog Input Module COM INPUT 1 INPUT 2 INPUT 3 INPUT 4 INPUT 5 HACVACO NKA INPUT 6 o0O000 000 INPUT 7 eo0o000 0000 00 ie INPUT 8 0 RESET J O Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 2 9 External I O Modules 9 2 O Module Installation See sections 3 3 and 5 6 for installation instructions for the external I O Modules 9 2 1 Power Source for O
119. r power and communication details Refer to Section 5 6 2 to determine if you must use an additional power source such as EIG s PSIO All outputs share a single common point This is also an isolated connection from ground The Modbus Map for the Analog Output Module and operating details can be found in the Modbus Communicating I O Modules Manual 9 5 2 Normal Mode Normal Mode is the same for the 0 1mA and the 4 20mA Analog Output Modules except for the number of processes performed by the modules Both devices 1 Accept new values through communication 2 Output current loops scaled from previously accepted values The 0 imA module includes one more process in its Normal Mode 3 Read and average the A D and adjust values for Process 2 above The device will operate with the following default parameters Address 247 F7H Baud Rate 57600 Baud Transmit Delay Time 20 msec Normal Operation is prevented by a number of occurrences See Section 9 4 for details 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 7 9 External I O Modules 9 6 Analog Input Modules Analog Input Module Specifications Model Numbers 8AI1 8 channel analog input O 1mA 8AI2 8 channel analog input O 20mA 8AI3 8 channel analog input O 5VDC 8AI4 8 channel analog input O 10VDC Accuracy 0 25 of Full Scale Scaling P
120. rate of 57600 and addresses For programming instructions refer to Chapter 8 of the Communicator EXT User Manual See the next page for the external displays VA Ratings NOTE For 24 or 48 VDC applications EIG recommends the PB1 power supply Example order number PB1 D 12VO PB1 If you are using a PSIO for 125V AC DC input or PB1 your maximum VA is 12 The Leader In Power Monitoring and Smart Grid Solutions Cj Electro Industries GaugeTech Doc E107706 5 12 5 Communication Wiring Nexus Display VA Ratings P41N P41N LED Displays 8VA P43N 5 7 Linking Multiple Nexus Meters in Series You may connect a total of 31 Nexus meters in series on a single bus using RS485 The cable length may not exceed 4000 feet 1219 meters Before assembling the bus each Nexus meter must be assigned a unique address See Chapter 3 of the Communicator EXT User Manual for instructions e Connect the and terminals of each Nexus meter Use jumpers on any RS485 Master connected at the end of the chain e Connect the shield to the S terminal on each Nexus meter and to the Ground on the RS485 Master This connection is used to reference the Nexus meter s port to the same potential as the source It is not an earth ground connection You must also connect the shield to earth ground at one point e Provide termination resistors at each end connected to the and lines RT is approximately
121. re common method of calculating power factor is the ratio of the real power to the apparent power This relationship is expressed in the following formula Total PF real power apparent power watts VA This formula calculates a power factor quantity known as Total Power Factor It is called Total PF because it is based on the ratios of the power delivered The delivered power quantities will include the impacts of any existing harmonic content If the volt age or current includes high levels of harmonic distortion the power values will be affected By calculating power factor from the power values the power factor will include the impact of harmonic distortion In many cases this is the preferred method of calculation because the entire impact of the actual voltage and current are included A second type of power factor is Displacement Power Factor Displacement PF is based on the angular relationship between the voltage and current Displacement power fac tor does not consider the magnitudes of voltage current or power It is solely based on the phase angle differences As a result it does not include the impact of harmonic distortion Displacement power factor is calculated using the following equation Displacement PF cos Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 13 1 Three Phase Power Measurement where 9 is the angle between the voltage and the curren
122. ring Polling Flicker Readings e Current Pst values for Va Vb and Vc and the time of computation e Current Pst Max values for Va Vb and Vc since the last reset and the time of the last reset e Current Pst Min values for Va Vb and Vc since the last reset and the time of the last reset Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 8 12 Flicker and Analysis Long Term Readings 1 Click on the Long Term tab to access a screen containing three groups of Plt readings shown below EN50160 IEC 61000 4 30 Flicker Time Short Term iLong Term Start Reset Voltsc 1 213 Max Volts A Max Volts B Max Volts C Min VoltsA 0 24 12 29 2010 16 00 00 08 Min Volts B Min Volts C Base Voltage Flicker Monitoring Polling Time Plt readings displayed e Current Pit values for Va Vb and Vc and the time of computation e Current Plt Max values for Va Vb and Vc since the last reset and the time of the last reset e Current Plt Min values for Va Vb and Vc since the last reset and the time of the last reset 2 Click OK to exit the EN50160 IEC61000 4 30 Flicker Polling screen click Print to print all of the Readings views 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 9 12 Flicker and Analysis 12 5 Logging The Nexus 1250 1252 meter is
123. ring and Smart Grid Solutions 5 Communication Wiring 5 8 3 1 Selected Modem Strings Modem String Setting Cardinal modem AT amp FEOF8 amp KONOS37 9 Zoom Faxmodem VFX AT amp FO amp KOSO 1 amp WO0 amp YO V 32BIS 14 4K Zoom Faxmodem 56Kx AT amp FO amp KO amp COS0 1 amp W0 amp Dual Mode YO USRobotics Sportster AT amp FO amp N6 amp WOYO for 33 6 Faxmodem 9600 baud DIP switch setting Up Up Down Down Up Up Up Down USRobotics Sportster 56K AT amp FO amp WOYO Faxmodem DIP switch setting Up Up Down Down Up Up Up Down 5 9 High Speed I nputs Connection The Nexus 1250 1252 meter s built in High Speed Inputs can be used in many ways e Attach the KYZ HS Outputs from other meters for totalizing e Attach relaying contacts for breaker status or initiated logging e Set as an Input Trigger for Historical Log 2 Refer to the Communicator EXT User Manual for instructions on programming these features Cj Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring The High Speed Inputs can be used with either dry or wet field contacts For Wet contacts the common rides on a unit generated Nominal 15V DC No user program ming is necessary to use either wet or dry field contacts 8 654321 Figure 5 11 High Speed Inputs Connections 5 10 IRIG B Connecti
124. rized in Table 1 3 Cause Disturbance Type Source Impulse transient Transient voltage disturbance Lightning sub cycle duration Electrostatic discharge Load switching Capacitor switching Oscillatory Transient voltage sub cycle Line cable switching transient with decay duration Capacitor switching Load switching Sag swell RMS voltage multiple cycle Remote system faults duration Interruptions RMS voltage multiple System protection seconds or longer duration Circuit breakers Fuses Maintenance Under voltage over voltage RMS voltage steady state Motor starting multiple seconds or longer Load variations duration Load dropping Voltage flicker RMS voltage steady state Intermittent loads repetitive condition Motor starting Arc furnaces Harmonic distortion Steady state current or volt Non linear loads age long term duration System resonance Table 1 3 Typical Power Quality Problems and Sources It is often assumed that power quality problems originate with the utility While it is true that may power quality problems can originate with the utility system many problems originate with customer equipment Customer caused problems may manifest themselves inside the customer location or they may be transported by the utility system to another adjacent customer Often equipment that is sensitive to power quality problems may in fact also be the cause of the problem If a power quality problem is
125. rogrammable Communication RS485 Modbus RTU Programmable Baud Rates 4800 9600 19200 38400 57600 Power Requirement 15 20VDC 50 200mA 1250 1252 supports up to four modules Operating Temperature 20 to 70 C 4 to 158 F Maximum Load Impedance O 1imA 10k Ohms 4 20mA 500 Ohms Factory Settings Modbus Address 8AI1 136 8AI2 140 8AI3 144 8AI4 148 Baud Rate 57600 Transmit Delay Time 0 Default Settings Reset Button Modbus Address 247 Baud Rate 57600 Transmit Delay Time 20msec 9 6 1 Overview The Analog Input Modules 0 1mA 0 20mA 0 5Vdc and 0 10Vdc are available in 8 channel format Maximum registers per request read or write is 17 registers The Nexus 1250 1252 meter supplies power for up to 4 connected Analog Input modules See Section 9 2 for power and communication details Refer to Section 5 6 2 to determine if you must use an additional power source such as EIG s PSIO All inputs share a single common point This is also an isolated connection from ground Cj Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 External I O Modules The Modbus Map for the Analog Output Module and operating details can be found in the Modbus Communicating O Modules Manual 9 6 2 Normal Mode In Normal Mode the Input Module 1 Reads and averages the A
126. rt Grid Solutions Doc E107706 Customer Service and Support Customer support is available 9 00 am to 4 30 pm Eastern Standard Time Monday through Friday Please have the model serial number and a detailed problem descrip tion available If the problem concerns a particular reading please have all meter readings available When returning any merchandise to EIG a return materials authorization number is required For customer or technical assistance repair or calibration phone 516 334 0870 or fax 516 338 4741 Product Warranty Electro Industries GaugeTech warrants all products to be free from defects in material and workmanship for a period of four years from the date of shipment During the warranty period we will at our option either repair or replace any product that proves to be defective To exercise this warranty fax or call our customer support department You will receive prompt assistance and return instructions Send the instrument transporta tion prepaid to EIG at 1800 Shames Drive Westbury NY 11590 Repairs will be made and the instrument will be returned This warranty does not apply to defects resulting from unauthorized modification misuse or use for any reason other than electrical power monitoring The Nexus 1252 meter is not a user serviceable product THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES EXPRESSED OR IMPLIED INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABIL ITY OR FITNESS FOR A
127. rview Electro Industries offers three external displays for use with the Nexus 1250 1252 meter The P40N and legacy P40N P41N and P43N are LED displays that provide easy to use access to the information stored in your Nexus meter The P40N display also features a USB port for direct data download Plug one of the Nexus external d plays into Port 3 or 4 of the meter using the cable supplied with the display The displays operate at 9600 baud Port 3 is already factory set to 9600 baud see Chapter 5 for communication details To use a display on another port configure that port to operate at 9600 baud with the Communicator EXT Software See Chapter 3 of the Communicator EXT User Manual for instructions on configuring the meter s port 6 2 Nexus P40N P40N P41N and P43N LED External Displays The Nexus P40N and P40N LED external display can be used alone or as the Master for a grouping of displays The P40N P40N prepares the data for the Slave displays the P41N and the P43N Once every second it sends a request to the Nexus meter All necessary data for the Slave displays is returned to the Master display upon this request and the Master sends the data to the Slaves in the proper format The Nexus P41N and P43N Slave displays listen to the Master and display and update values on the screen when they receive proper data These displays have no keypads Data can only be received it cannot be changed If
128. s The Nexus meter s ports support 12 VA Each P40N P40N P41N or P43N requires 3 3 VA maximum 3 8 VA The Master display P40N is the master in communication The Amp Power and Nexus devices are slaves in communication Therefore the Master display P40N should be at the end of the daisy chained units as shown in Figure 6 2 RS485 Communication Figure 6 2 Daisy Chaining Displays 6 2 2 Nexus P40N P40N Display Modes The Nexus P40N P40N LED external display has three modes e Dynamic Readings mode sections 6 3 and 6 4 e Nexus Information mode sections 6 5 and 6 6 e Display Features mode sections 6 7 and 6 8 Each mode is divided into groups Most groups are further broken down into readings e Use the MODE button to scroll between modes 3 Electro Industries GaugeTech Doc E107706 ee The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays e Use the UP DOWN arrows to scroll from group to group within each mode e Use the LEFT RIGHT arrows to scroll from reading to reading within each group Use the Communicator EXT software to Flash Update the P40N P40N external display Refer to the Communicator EXT User Manual for instructions 6 3 Dynamic Readings Mode The External Display puts itself in the Dynamic Readings Mode upon power up Use the Mode button to access the DynamicReadings from other Modes Use the Up Down arrows to navigate from Gro
129. s access to additional Nexus meters via the LAN Simply con nect a daisy chain of Nexus meters together via RS485 each with its own device address and using the same baudrates With this option you can access any of those instruments via the single LAN connection The Internal Network Option allows multiple simultaneous connections via LAN to the Nexus meter You can access the meter with SCADA MV90 and RTU simultane ously The Internal Network Option allows multiple users running Communicator EXT soft ware to access the meter concurrently 11 2 Network Connection Use Standard RJ45 10 100BaseT cable to connect with the Nexus meter Insert the RJ45 line into the RJ45 Port on the face of a Nexus 1250 1252 meter with the Inter nal Network Option Set the IP Address using the following steps Refer to Section 3 3 5 of the Communi cator EXT User Manual for more detailed instructions 1 From the Device Profile screen double click General Settings gt Communica tions then double click on any of the ports The Communications Settings screen opens Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 11 2 11 Meter with Internal Network Option 2 In the Network Settings section enter the following data Consult your System Administrator if you do not know this information IP Address 10 0 0 1 Example Subnet Mask 255 255 255 0 Example
130. source such as EIG s PSIO Ci Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 External I O Modules The Modbus Map for the KYZ Pulse Output Module and operating details can be found in the Modbus Communicating I O Modules Manual NC Normally Closed NO Normally Open C Common 9 8 2 Communication Maximum registers per request read or write is 4 registers The device will operate with the following Default Mode Parameters See Section 9 4 for details Address 247 F7H Baud Rate 57600 Baud Transmit Delay Time 20 msec 9 8 3 Normal Mode Energy readings are given to the device frequently The device generates a pulse at each channel after a certain energy increase Normal Operation consists of three processes 1 The first process accepts writes to registers 04097 04112 Writes can be up to four registers long and should end on the fourth register of a group register 04100 or registers 04103 04112 or registers 04109 04112 These writes can be interpreted as two byte four byte six byte or eight byte energy readings The reception of the first value for a given channel provides the initial value for that channel Subsequent writes will increment the Residual for that channel by the difference of the old value and the new value The previous value is then replaced with the new value Attempting to write a value greater than the programmed Rollover V
131. ss filter 1st order 5 Statistical computing Data available e Pst Pst Max Pst Min values for short term recording e Plt Plt Max Plt Min values for long term recording Simulation Of Eye Brain Response Block 1 Block 2 Block 3 Block 4 Block 5 Voltage Detector High Pass A D and Gain Filter Converter Minimum Output Control DC tst Sampling 64 level inernace Square Removal Weighting Squaring Order Rate Classifier Law Filter Multiplier Sling gt 50Hz Demodulator Low Mean Pass Filter Filter Input Carrier Voltage Removal Adaptor Programming of short and long observation periods Output Recording Output and Data Display Instantaneous Flicker in Pst Max Min Pst Perceptibility Units Plt Max Min Plt Pinst Figure 12 1 Simulation of Eye Brain Response 12 3 Flicker Setting Nexus 1250 meter and 1252 V 1 You must set up several parameters to properly configure Flicker NOTE If your Nexus 1252 meter has V Switch key 2 see Section 12 9 for instruc tions on configuring EN50160 IEC61000 4 30 Power Quality Compliance analysis including Flicker 1 Select the Profile icon from Communicator EXT s Icon bar 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 4 12 Flicker and Analysis 2 From the Device Profile screen double click Power Quality and Alarm Set tings g
132. sured readings Refer to Appendix B in the Communicator EXT User Manual for instructions Loss compensation values must be calculated based on the meter installation As a result transformer loss values must be normalized to the meter by converting the base voltage and current and taking into account the number of elements used in the Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 4 7 Transformer Loss Compensation metering installation For three element meters the installation must be normalized to the phase to neutral voltage and the phase current in two element meters the installation must be normalized to the phase to phase voltage and the phase current This process is described in the following sections 7 2 1 Loss Compensation in Three Element Installations Loss compensation is based on the loss and impedance values provided on the trans former manufacturer s test report A typical test report will include at least the follow ing information e Manufacturer e Unit Serial Number e Transformer MVA Rating Self Cooled e Test Voltage e No Load Loss Watts e Load Loss Watts or Full Load Loss Watts e Exciting Current 100 voltage e Impedance The transformer MVA rating is generally the lowest MVA rating the self cooled or OA rating of the transformer winding The test voltage is generally the nominal voltage of the secondary or low voltage windi
133. suspected it is generally wise to consult a power quality professional for assistance in defining the cause and possible solutions to the problem 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 18 2 Meter Overview 2 Meter Overview This chapter provides basic information on the Nexus 1250 1252 meter 2 1 The Nexus System Electro Industries Nexus 1250 1252 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 The P40N P41N and P43N displays are detailed in Chapter 6 Extensive I O capability is available in conjunction with all metering functions The optional Communicator EXT software allows a user to poll and gather data from multiple Nexus meters installed at local or remote locations see the Communicator EXT User Manual for details On board mass memory enables the meter to retrieve and store multiple logs The Nexus meter with Internal Modem or Network Option connects to a PC via standard phone line or MODBUS TCP and a daisy chain of Nexus meters via an RS485 connection See Chapters 10 and 11 for details Nexus 1250 1252 Revenue Metering e Delivers laboratory grade 0 04 Watt hour accuracy at full load Unity PF in a field mounted device e Auto calibrates when there is a temperature
134. t see Fig 1 9 In applications where the voltage and current are not distorted the Total Power Factor will equal the Displacement Power Factor But if harmonic distortion is present the two power factors will not be equal 1 4 Harmonic Distortion Harmonic distortion is primarily the result of high concentrations of non linear loads Devices such as computer power supplies variable speed drives and fluorescent light ballasts make current demands that do not match the sinusoidal waveform of AC electricity As a result the current waveform feeding these loads is periodic but not sinusoidal Figure 1 10 shows a normal sinusoidal current waveform This example has no distortion 1000 500 Time o Amps 500 1000 Figure 1 10 Nondistorted Current Waveform Figure 1 11 shows a current waveform with a slight amount of harmonic distortion The waveform is still periodic and is fluctuating at the normal 60 Hz frequency However the waveform is not a smooth sinusoidal form as seen in Figure 1 10 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 14 1 Three Phase Power Measurement a Current amps AA Figure 1 11 Distorted Current Waveform The distortion observed in Figure 1 11 can be modeled as the sum of several sinusoi dal waveforms of frequencies that are multiples of the fundamental 60 Hz fre
135. t EN50160 I EC61000 4 30 Flicker You will see the screen shown below EN50160 IEC 61000 4 30 Flicker Frequency 60 Hz Short term test time PST fio gt Minutes Long term test time PLT 240 Minutes EE ae e Select the Frequency of operation 50 Hz is the approved frequency according to Flicker standards A 60 Hz implementation is available and can be selected Remember the voltage is normalized For 50 Hz the normalized voltage is 230 V and for 60 Hz the normalized voltage is 120 V e Select a Short Term Test Time PST time range from 1 to 10 minutes The standard measurement period is nominally 10 minutes e Select a Long Term Test Time PLT time range from 1 to 240 minutes The standard measurement is nominally 12 Pst periods 120 minutes Plt time must always be equal to or greater than and a multiple of Pst time This is reflected in the available selections 3 Click OK when you are finished Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 5 12 Flicker and Analysis 12 4 Flicker Polling Screen 1 From the Communicator EXT Title bar select Real Time Poll gt Power Quality and Alarms gt Flicker You will see the screen shown below EN50160 IEC 61000 4 30 Flicker ile OStantaneous Short Term Long Term Star Reset 2 07 2010 110 2 PINST Voltage Reading St Ay Volts A Current Yolts B Next PST Next PLT Volts C
136. t against any firm flat surface Use a 10 screw in each of the four slots on the flange to ensure that the unit is installed securely For safety reasons mount the meter in an enclosed and protected environment such as in a switchgear cabinet Install a switch or circuit breaker nearby label it clearly as the meter s disconnecting mechanism NOTE The Nexus meter with the Internal Modem Option mounts the same way Maintain the following conditions e Operating Temperature 40 C to 70 C 40 F to 158 F e Storage Temperature 40 C to 70 C 40 F to 158 F e Relative Humidity 5 to 95 non condensing 10 630 27cm m 2X3 315 X8 42cm 2X 4 000 10 2em E g 6 131 X15 57cm 6 740 17 12cm 1 i gt 4X 0 221 56cm Through slots for 10 screw Figure 3 1 Nexus 1250 1252 Mounting Diagram Top View Cj Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 3 Hardware Installation m 2 36 5 99cm 3 36 8 96cm MAX Figure 3 2 Nexus 1250 1252 Mounting Diagram Side View 3 2 Mounting the Nexus LED External Displays The
137. t is a more effective way to transmit the power and because it provides a smoother delivery of power to the end load There are two commonly used connections for three phase power a wye connection or a delta connection Each connection has several different manifestations in actual use When attempting to determine the type of connection in use it is a good practice to follow the circuit back to the transformer that is serving the circuit It is often not possible to conclusively determine the correct circuit connection simply by counting the wires in the service or checking voltages Checking the transformer connection will provide conclusive evidence of the circuit connection and the relationships between the phase voltages and ground 1 1 1 Wye Connection The wye connection is so called because when you look at the phase relationships and the winding relationships between the phases it looks like a Y Figure 1 1 depicts the winding relationships for a wye connected service In a wye service the neutral or center point of the wye is typically grounded This leads to common voltages of 208 120 and 480 277 where the first number represents the phase to phase voltage and the second number represents the phase to ground voltage 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 1 1 Three Phase Power Measurement Ve Phase 2 N Phase 3 Phase 1 VB m Va Figure 1 1 Thre
138. terval averages as programmed to produce the Rolling Window Demand Example With settings of 3 five minute subintervals subinterval averages are com puted every 5 minutes 12 00 12 05 12 15 etc for power readings over the previous five minute interval 11 55 12 00 12 00 12 05 12 05 12 10 12 10 12 15 etc In addition every 5 minutes the subinterval averages are averaged in groups of 3 12 00 12 05 12 10 12 15 etc to produce a fifteen 5x3 minute average every 5 minutes rolling sliding every 5 minutes 11 55 12 10 12 00 12 15 etc Thermal Demand Traditional analog Watt hour Wh meters use heat sensitive elements to measure temperature rises produced by an increase in current flowing through the meter A pointer moves in proportion to the temperature change providing a record of demand The pointer remains at peak level until a subsequent increase in demand moves it again or until it is manually reset The Nexus 1250 1252 mimics traditional meters to provide Thermal Demand readings Each second as a new power level is computed a recurrence relation formula is applied This formula recomputes the thermal demand by averaging a small portion of the new power value with a large portion of the previous thermal demand value The proportioning of new to previous is programmable set by an averaging interval The averaging interval represents a 90 change in thermal demand to a step change in power Predictive
139. to Blocks 2 3 and 4 For the specified 50 Hz operation the voltage standard is 230 V RMS e Block 2 recovers the voltage fluctuation by squaring the input voltage scaled to the reference level This simulates the behavior of a lamp e Block 3 is composed of a cascade of two filters and a measuring range selector In this implementation a log classifier covers the full scale in use so the gain sdection is automatic and not shown here The first filter eliminates the DC component and the double mains frequency components of the demodulated output The configura Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 12 1 12 Flicker and Analysis tion consists of a 05 Hz Low High Pass filter and a 6 Pole Butterworth Low Pass filter located at 35 Hz The second filter is a weighting filter that simulates the response of the human visual system to sinusoidal voltage fluctuations of a coiled filament gas filled lamp 60 W 230 V The filter implementation of this function is as specified in IEC 61000 4 15 e Block 4 is composed of a squaring multiplier and a Low Pass filter The Human Flicker Sensation via lamp eye and brain is simulated by the combined non linear response of Blocks 2 3 and 4 e Block 5 performs an online statistical cumulative probability analysis of the Flicker level Block 5 allows direct calculation of the evaluation parameters Pst and Pit Flicker E
140. tored Inputs Currents Install the cables for the current at 600VAC minimum insulation The cable connector should be rated at 10 Amps or greater and have a cross sectional area of 14 AWG Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 4 3 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 EI G Recommendations Maximum erie RTO Nexus Meter Ft 2 5 10 5 15 7 5 30 10 40 15 60 30 120 WARNI NG DO NOT leave the secondary of the CT open when primary current is flowing This may cause high voltage which will overheat the CT If the CT is not connected provide a shorting block on the secondary of the CT It is important to maintain the polarity of the CT circuit when connecting to the Nexus 1250 1252 meter If the polarity is reversed the meter will not provide accu rate readings CT polarities are dependent upon correct connection of CT leads and the direction CTs are facing when clamped around the conductors Although shorting blocks are not required for proper meter operation EIG recommends using shorting blocks to allow removal of the Nexus 1250 1252 meter from an energized circuit if necessary 3 Electro Industries GaugeTech The Lead
141. tro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 6 7 Transformer Loss Compensation Value Watts Loss 3 Phase 1 Phase 1 Phase kW No Load Loss Load Loss Enter 3 Phase or i1 Phase values If 3 Phase values are entered calculate 1 Phase values by dividing 3 Phase values by three Convert 1 Phase Loss Watts to 1 Phase kW by dividing 1 Phase Loss Watts by 1000 Value 3 Phase MVA 1 Phase MVA 1 Phase kVA Self Cooled Rating Enter 3 Phase or 1 Phase values If 3 Phase values are entered calculate 1 Phase values by dividing 3 Phase values by three Convert 1 Phase Self Cooled MVA to 1 Phase kVA by multiplying by 1000 Exciting Current Impedance Value Phase to Phase Phase to Neutral Test Voltage Volts Full Load Current Amps Test Voltage is generally Phase to Phase for three phase transformers Calculate Phase to Neutral Voltage by dividing Phase to Phase Voltage by the square root of 3 Calculate Full Load Current by dividing the 1 Phase kW Self Cooled Rating by the Phase to Neutral Voltage and multiplying by 1000 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 7 7 7 Transformer Loss Compensation Meter Installation Data Instrument Transformers Numerator Denominator Multiplier
142. typically tied to the ground or center point of the wye In many industrial applications the facility will be fed with a four wire wye service but only three wires will be run to individual loads The load is then often referred to as a delta connected load but the service to the facility is still a wye service it contains four wires if you trace the circuit back to its source usually a transformer In this type of connection the phase to ground voltage will be the phase to ground voltage indicated in Table 1 even though a neutral or ground wire is not physically present at the load The transformer is the best place to determine the circuit connection type because this is a location where the voltage reference to ground can be conclusively identified Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 Three Phase Power Measurement 1 1 2 Delta Connection Delta connected services may be fed with either three wires or four wires In a three phase delta service the load windings are connected from phase to phase rather than from phase to ground Figure 1 3 shows the physical load connections for a delta service Vo Phase 3 Phase 2 Ve Phase 1 Va Figure 1 3 Three phase Delta Winding Relationship In this example of a delta service three wires will transmit the power to the load Ina true delta service the phase to ground voltage will usually not be balanced because
143. uctures The Nexus meter s TOU function accumu lates data based on the time scheme programmed into the meter See Chapter 10 of the Communicator EXT User Manual for details on programming the Nexus 1250 1252 meter s 20 year TOU calendar and retrieving TOU data 8 2 The Nexus Meter s TOU Calendar A Nexus TOU calendar sets the parameters for TOU data accumulation You may store up to twenty calendars in the Nexus 1250 1252 meter and an unlimited amount of calendar files on your computer The Nexus TOU calendar profile allows you to assign a programmable usage sched ule e g Weekday Weekend or Holiday to each day of the calendar year You may create up to 16 different TOU schedules Each TOU schedule divides the 24 hour day into fifteen minute intervals from 00 00 00 to 23 59 59 You may apply one of eight different programmable registers e g Peak Off Peak or Shoulder Peak to each fifteen minute interval The Nexus 1250 1252 meter stores e Accumulations on a seasonal basis up to four seasons per year e Accumulations on a monthly basis Seasonal and monthly accumulations may span from one year into the next Each season and month is defined by a programmable start billing date which is also the end date of the prior season or month A season ends at midnight of the day before the start of the next season A month ends at midnight of the month s billing day a 3 Electro Industri
144. umper wire to make the terminal and connect the RX and TX terminals with a jumper wire to make the Set switch terminal See the figure on the right for the to FD Unicom 2500 s settings The Unicom s Baud rate must match the Baud rate of the meter s RS485 port you set the Baud rate by turn ing the screw to point at the rate you want 5 3 4 RS485 Connection to the Nexus P40N External Display Insert one end of the supplied RS485 cable into Port 3 of the Nexus 1250 1252 meter Port 3 is factory set to match the Nexus display s baud rate of 9600 To use a port other than Port 3 you must set the port s baud rate to 9600 using the Communicator EXT software see Chapter 3 of the Communicator EXT User Manual for instructions Insert the other end of the cable into the back of the Nexus P40N P40N P41N or P43N display The connectors fit only one way into the ports The cable harness brings 17V DC to the displays from the Nexus meter RS485 communication is viable for up to 4000 feet 1219 meters If your cable length exceeds 200 feet you must use a remote power supply such as EIG s PSIO and 1 Connect the shield to the shield S terminal on the Nexus display port The S terminal on the Nexus meter is used to reference the Nexus meter s port to the same potential as the source Itis not an earth ground connection You must also connect the shield to earth ground at one point 2
145. up to Group within this Mode See Section 6 4 for a Navi gation map of the Dynamic Readings Mode Group 1 Phase to Neutral Voltages Use the Left Right arrows to access the fol lowing readings in order Volts AN BN CN e Maximum Volts AN BN CN e Minimum Volts AN BN CN Volts AN BN CN THD Volts AN BN CN Maximum THD Volts AN BN CN Minimum THD Group 2 Phase to Phase Voltages Use the Left Right arrows to access the follow ing readings in order e Volts AB BC CA e Minimum Volts AB BC CA e Maximum Volts AB BC CA Group 3 Current Use the Left Right arrows to access the following readings in order e Current A B C a 3 Electro Industries GaugeTech Doc E107706 6 7 The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays e Maximum Current e Minimum Current e Current THD e Current Maximum THD e Current Minimum THD e Current Calculated N Measured N e Maximum Current Calculated N Measured N Group 4 Watt VAR Use the Left Right arrows to access the following readings in order e kWatt kVAR e Maximum kWatt kVAR CoIn kVAR e Maximum kWatt kKVAR CoIn kVAR Block Fixed Window Average Maximum kWatt kVAR CoIn kVAR e Predictive Rolling Sliding Window Maximum kWatt kVAR CoIn kVAR Group 5 VA PF Frequency Use the Left Right arrows to access the following read ings in order e kVA PF lag Hz e Maximum kVA Hz e Minimum kVA H
146. ustries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 9 External I O Modules 9 9 2 Communication Maximum registers per request read or write is 4 registers The device will operate with the following Default Mode Parameters See Section 9 4 for details Address 247 F7H Baud Rate 57600 Baud Transmit Delay Time 20 msec 9 9 3 Normal Mode The device polls the inputs at 100Hz once every 10 msec debouncing the inputs and incrementing the Transition Accumulators for each channel as appropriate The inputs are represented by Channel 1 in the LSB through Channel 8 in the MSB of the low order byte of the register The Modbus Map for the Digital Status Input Modules and operating details can be found in the Modbus Communicating O Modules Manual Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 10 Meter with Internal Modem Option 10 Meter with Internal Modem Option I NP2 10 1 Hardware Overview The Nexus 1250 1252 meter with the INP2 Internal Modem Option has all the components of the standard Nexus meter plus the capability of connecting to a PC via a standard phone line No additional hardware is required to establish this connec tion If desired the internal expansion port of the Nexus 1250 1252 meter can be config ured with an internal 56K bps modem This gives the meter Dial In and Dial Out
147. ut this value may vary based on length of cable run gauge and the impedance of the wire See RT EXPLANATION in Section 5 3 Cj Electro Industries GaugeTech Doc E107706 5 7 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring 5 3 3 Using the Unicom 2500 The Unicom 2500 provides RS485 RS232 conversion In doing so it allows the Nexus 1250 1252 meter to communicate with a PC or other device See the Unicom 2500 Installation and Operation Manual for additional information You can order the Unicom 2500 from EIG s webstore www electroind com store Select the Communi cations Products category from the left side of the webpage Figure 5 7 illustrates the Unicom 2500 connections for RS485 RS232 Port UNICOM 2500 TX RX TX RX SH Jumpers Short TX to RX becomes signal Short TX to RX becomes signal sx Meter s RS485 Port Figure 5 7 Meter Connected to PC using Unicom 2500 3 Electro Industries GaugeTech l The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 5 8 5 Communication Wiring The Unicom 2500 can be configured for either 4 f Set switch Set the to DCE wire or 2 wire RS485 connections Since the Baud rate Nexus meter uses a 2 wire connection you need to add jumper wires to convert the Unicom 2500 to the 2 wire configuration As shown in Figure 5 7 you connect the RX and TX terminals with a j
148. utton at the top of the screen and then enter the following information e Device Address 1 e Host IP Address per your network administrator Example 10 0 0 1 e Network Port 502 e Protocol Modbus TCP d Click the Connect button at the bottom of the screen Communicator EXT connects to the meter via the Network settings you entered Cj Electro Industries GaugeTech Doc E107706 2 7 The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview 2 6 Measurements and Calculations The Nexus 1250 1252 meter measures many different power parameters Following is a list of the formulas used to perform calculations with samples for Wye and Delta services Samples for Wye Va Vo Ve lar iby ler in Samples for Delta Vav Vbo Veer la b ic Root Mean Square RMS of Phase Voltages N number of samples For Wye x a b c Root Mean Square RMS of Line Currents N number of samples For Wye x a b c n For Delta x a b c Root Mean Square RMS of Line Voltages N number of samples For Wye x y a b or b c or c a Electra Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview For Delta xy ab bc ca Power Watts per phase N number of samples For Wye x a b c N ee eLa t 1 Wy 7 Apparent Power VA per phase For Wye x a b c VA V eJ x RMSy RMS y Reactive Power VAR per
149. val The thermal average rises to 90 of the actual value in each time interval For example if a constant 100Amp load is applied the thermal average will indicate 90 amps after one time interval 99 amps after two time intervals and 99 9 amps after three time intervals Average Input Pulse When applied to Input Pulse Accumulations the Accumulations Average refers to the block fixed window average value of the input pulses 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 1 Glossary Average Power When applied to power values Watts VARs VA the average is a calculated value that corresponds to the thermal average over a specified time interval The interval is specified by the user in the meter profile The interval is typically 15 minutes So the Average Watts is the thermal average of Watts over the previous 15 minute interval The thermal average rises to 90 of the actual value in each time interval For example if a constant 100kW load is applied the thermal average will indicate 90kW after one time interval 99kW after two time intervals and 99 9kW after three time intervals Bit A unit of computer information equivalent to the result of a choice between two alternatives Yes No On Off for example Or the physical representation of a bit by an electrical pulse whose presence or absence indicates data Binary Relating to a s
150. valuation occurs in the following forms Instantaneous Short Term or Long Term Each form is detailed below e Instantaneous Flicker Evaluation An output of 1 00 from Block 4 corresponds to the Reference Human Flicker Perceptibility Threshold for 50 of the population This value is measured in Perceptibility Units PU and is labeled Pinst This is a real time value and it is continuously updated e Short Term Flicker Evaluation An output of 1 00 from Block 5 corresponding to the Pst value corresponds to the conventional threshold of irritability per IEC 1000 3 3 In order to evaluate Flicker severity two parameters have been defined one for the short term called Pst defined in this section and one for the long term called Pit defined in the next section The standard measurement time for Pst is 10 minutes Pst is derived from the time at level statistics obtained from the level classifier in Block 5 of the Flicker meter The following formula is used P 0 03 147 0 0525P 0 0657 P 0 28 P p 0 08 Pos where the percentiles P 0 1 P 1 P 3 P 10 P 50 are the Flicker levels exceeded for 0 1 1 2 20 and 50 of the time during the observation period The suffix S in the formula indicates that the smoothed value should be used The smoothed values are obtained using the following formulas P 1s P 7 P 1 P 1 5 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Gri
151. voltage and current simultaneously and calculate the individual phase and three phase power values The advantage of simultaneous sampling is the reduction of error introduced due to the difference in time when the samples were taken Phase B Phase A Figure 1 6 Three Phase Wye Load Illustrating Kirchhoff s Law and Blondell s Theorem Blondell s Theorem is a derivation that results from Kirchhoff s Law Kirchhoff s Law states that the sum of the currents into a node is zero Another way of stating the same thing is that the current into a node connection point must equal the current out of the node The law can be applied to measuring three phase loads Figure 1 6 shows a typical connection of a three phase load applied to a three phase four wire service Krichhoff s Law holds that the sum of currents A B C and N must equal zero or that the sum of currents into Node n must equal zero Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 1 7 1 Three Phase Power Measurement If we measure the currents in wires A B and C we then know the current in wire N by Kirchhoff s Law and it is not necessary to measure it This fact leads us to the conclu sion of Blondell s Theorem that we only need to measure the power in three of the four wires if they are connected by a common node In the circuit of Figure 1 6 we must measure the power flow in three wires This will requ
152. wer Voltage 15 20VDC at 5 200mA Maximum Auxiliary Power Current 1A short protected Maximum Power Supply Range 100 250 VAC UL Listing 61010 1 not evaluated for accuracy reliability or capability to perform intended function Flicker Nexus 1252 Evaluation per IEC 61000 4 15 EN50160 1EC 61000 4 30 PQ Analysis Evaluation per IEC 61000 4 30 IRIG B Port Impedance 8MA 5V EN50160 EN61000 4 30 PQ Analysis is only available for a Nexus 1252 meter with V Switch key 2 2 10 Nexus P40N P41N P43N LED External Display Specifications Specification P40N P41N P43N Displays Maximum Input Voltage 30VDC Minimum Input Voltage 12VDC Maximum Power Consumption 5W Nominal Power Consumption Approximately 3W Operating Temperature Range 20 to 70 C 4 to 158 F 5 25 x 5 25 x1 79 inches 13 34 x 13 34 x 4 54 cm Overall Dimensions HxWxD Electra Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview The legacy P40N dimensions are 4 4 x 4 4 x 2 2 inches 11 1 x 11 1 x 5 9cm 2 11 Upgrading the Nexus 1252 Meter s V Switch Key The Nexus 1252 meter s base configuration is V Switch key 1 V 1 To upgrade your meter to a higher V Switch key e g V 2 follow these steps 1 Obtain a V Switch upgrade key by contacting EIG s inside sales staff at sales electroind co
153. with modem commu nication You must change the protocol to Modbus ASCII You must use an RS485 to RS232 converter and a Null Modem EIG recommends using its Modem Manager a sophisticated RS232 RS485 converter that enables devices with different baud rates to communicate It also eliminates the need for a Null modem 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 5 8 3 Programming Modems for Remote Communication You must program a modem before it can communicate properly with most RS485 or RS232 based devices This task is often quite complicated because modems can be unpredictable when communicating with remote devices If you are not using the EIG Modem Manager device you must set the following strings to communicate with the remote Nexus meter s Consult your modem s manual for the proper string settings or see Section 5 8 3 1 for a list of selected modem strings NOTE Use a Modem Manager The product was designed to make this task plug and play We highly recommend it for all serial modem solutions 3 Electro Industries GaugeTech Doc E107706 5 15 The Leader In Power Monitoring and Smart Grid Solutions 5 Communication Wiring Modem Connected to a Computer the Originate Modem e Restore modem to factory settings This erases all previously programmed settings
154. your system administrator if you are not sure of the information to enter e P Address For example 10 0 0 1 e Subnet Mask For example 255 255 255 0 e Default Gateway For example 0 0 0 0 e Computer Name For example NETWORK 5 Enter the Domain Name Server and Computer Name Ci Electro Industries GaugeTech Doc E107706 2 6 The Leader In Power Monitoring and Smart Grid Solutions 2 Meter Overview 6 Default web pages with an extensive array of readings come with the meter The content of the pages can be customized using FTP Client Follow these steps a Click the Advanced Settings button in the Communications Settings screen b Click the FTP Client tab on the top of the Advanced Settings screen Using FTP you can easily replace any file by using the same file name as the one you want to replace c Click OK 7 Enter the Email Server IP Address The Default Settings store one Email Server IP Address for administrative purposes or to send an alarm if there is a problem An additional 8 email addresses can be configured with FTP Client 8 Update Firmware if necessary with TFTP protocol see Appendix C 9 After the parameters are configured Communicator EXT connects via the Network using a Device Address of 1 and the assigned IP Address when you follow these steps a Open Communicator EXT software b Click the Connect icon in the Icon tool bar to open the Connect screen c Click the Network b
155. ystem of numbers having 2 as its base digits 0 and 1 Block Window Avg Power The Block Fixed Window Average is the average power calculated over a user set time interval typically 15 minutes This calculated average corresponds to the demand calculations performed by most electric utilities in monitoring user power demand See Rolling Window Average 3 Electro Industries GaugeTech The Leader In Power Monitoring and Smart Grid Solutions Doc E107706 GL 2 Glossary Byte CBEMA Curve Channel Cold Load Pickup CRC Field CT Current Ratio Cumulative Demand A group of 8 binary digits processed as a unit by a computer or device and used especially to represent an alphanumeric character A voltage quality curve established originally by the Computer Business Equipment Manufacturers Association The CBEMA Curve defines voltage disturbances that could cause malfunction or damage in microprocessor devices The curve is characterized by voltage magnitude and the duration which the voltage is outside of tolerance See ITIC Curve The storage of a single value in each interval in a load profile This value is the delay from the time control power is restored to the time when the user wants to resume demand accumulation Cyclic Redundancy Check Field Modbus communication is an error checksum calculation that enables a Slave device to determine if a request packet from a Master
156. z e Maximum Quadrant 1 Total PF e Minimum Quadrant 1 Total PF e Maximum Quadrant 2 Total PF e Minimum Quadrant 2 Total PF Cj Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays e Maximum Quadrant 3 Total PF e Minimum Quadrant 3 Total PF e Maximum Quadrant 4 Total PF e Minimum Quadrant 4 Total PF Group 6 Delivered Energy Use the Left Right arrows to access the following read ings in order e kWatthr Quadrant 1 Quadrant 4 Primary e kVAhr Quadrant 1 Primary e kVARhr Quadrant 1 Primary e kVAhr Quadrant 4 Primary e kVARhr Quadrant 4 Primary Group 7 Received Energy Use the Left Right arrows to access the following read ings in order e kWatthr Quadrant 2 Quadrant 3 Primary e kVAhr Quadrant 2 Primary e kVARhr Quadrant 2 Primary e kVAhr Quadrant 3 Primary e kVARhr Quadrant 3 Primary Group 8 Accumulations Use the Left Right arrows to access the following read ings in order e kI2tA e kI2tB e kI2tC Electro Industries GaugeTech Doc E107706 The Leader In Power Monitoring and Smart Grid Solutions 6 Using the External Displays e kV2tA e kV2t B e kV2t C Group 9 Phase Angles Use the Left Right arrows to access the following readings in order e Phase Angle Van bn cn e Phase Angle Ia b c e Phase Angle Vab bc ca e Phase Sequence

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