LED INDICATORS ..................... 4-2 4.1.5 PROGRAM PORT....................4-3 4.1.6 KEYPAD......................4-3 4.2 745PC SOFTWARE INTERFACE 4.2.1 OVERVIEW......................4-5 4.2.2 REQUIREMENTS ....................4-5 4.2.3 TOOLBAR AND MENUS ................... 4-5 4.2.4 HARDWARE CONFIGURATION ............... 4-6 GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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5.6.10 FREQUENCY ....................5-68 5.6.11 OVEREXCITATION ..................5-73 5.6.12 HARMONICS ....................5-77 5.6.13 INSULATION AGING / LOSS OF LIFE ............5-80 5.6.14 ANALOG LEVEL....................5-84 5.6.15 CURRENT DEMAND..................5-85 5.6.16 TRANSFORMER OVERLOAD .................5-86 5.6.17 TAP CHANGER FAILURE................5-87 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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PROTOCOLS..................... 7-1 7.1.2 PHYSICAL LAYER..................... 7-1 7.2 MODBUS PROTOCOL 7.2.1 DESCRIPTION....................7-2 7.2.2 GE MULTILIN MODBUS IMPLEMENTATION ........... 7-2 7.2.3 ELECTRICAL INTERFACE................7-2 7.2.4 DATA FRAME FORMAT AND DATA RATE ............7-2 7.2.5 DATA PACKET FORMAT .................. 7-3 GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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FREQUENCY ....................8-29 8.5.14 OVEREXCITATION ..................8-34 8.5.15 INSULATION AGING..................8-35 8.5.16 TAP MONITOR FAILURE.................8-35 8.6 AUXILIARY PROTECTION AND MONITORING FUNCTIONS 8.6.1 THD LEVEL SCHEME ..................8-36 8.6.2 HARMONIC DERATING FUNCTION ...............8-37 8.6.3 TRANSFORMER OVERLOAD .................8-37 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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TABLE OF CONTENTS 8.7 PLACING THE RELAY INTO SERVICE 8.7.1 PROCEDURE ....................8-38 A. APPENDIX A.1 EU DECLARATION A.1.1 DECLARATION OF CONFORMITY ..............A-1 A.2 WARRANTY A.2.1 GE MULTILIN WARRANTY ................A-2 GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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TABLE OF CONTENTS viii 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Analog Input Level 1 1THD Total Harmonic Distortion Level AN-2 Analog Input Level 2 Current Demand Insulation Aging: • Aging Factor • Hottest Spot Limit • Total Accumulated Life Tap Changer Monitor GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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Ground Differential (Restricted Ground Fault) 251G Ground Time Overcurrent 3THD Total Harmonic Distortion Level 287TG Ground Differential (Restricted Ground Fault) Current Demand 2THD Total Harmonic Distortion Level Current Demand Figure 1–1: SINGLE LINE DIAGRAM 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
40 to 60 V DC; 20 to 48 V AC at 48 to 62 Hz POWER 90 to 300 V DC; 70 to 265 V AC at 48 to 62 Hz OPTIONS Analog Inputs/Outputs Loss of Life Restricted Ground Fault GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
1.0 to 10 V pk-pk Overload Withstand: 1 second at 80 times rated current DC Shift: 2 seconds at 40 times rated current Input Impedance 70 to 100 kΩ continuous at 3 times rated current 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Winding 1 Phase A current / voltage Level Accuracy: ±0.02 Hz Operate Time: The operate time of the frequency trend element is variable and is dependent on the decay rate setting and the supervi- sion frequency level. GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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Solid State Output Operate Time: at 1.10 × pickup: 165 to 195 ms Relay Outputs 2 to 5 Operate Time: at 1.10 × pickup: 170 to 200 ms (delay set at 0.0 s) 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Operational test at ambient then increas- ing to 60°C Dielectric Strength: Per IEC 255-5 and ANSI/IEEE C37.90 On CT inputs, VT inputs, Control Power inputs, Switch inputs, and Relay outputs (2 kV for 1 second) GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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It is recommended that all 745 relays be powered up at least once per year to avoid deterioration of electro- lytic capacitors in the power supply. NOTE Specifications subject to change without notice. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
), either starts with an upper- 4.0 s case character followed by lowercase characters or is a number followed by units. This second part is the present value of the data. FLASH MESSAGE TIME: 4.0 s GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
HELP MINIMUM: 60.0 MAXIMUM: 120.0 IN STEPS OF: PRESS (0)-(9) OR VALUE PRESS [ENTER] TO STORE NEW VALUE END OF PAGE S1 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Editing changes are not registered until is pressed, storing the new value in memory. This flash message momen- ENTER tarily appears to confirm the storing process. NEW SETPOINT HAS BEEN STORED GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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Once complete, press to remove ESCAPE the solid cursor and view the result. OUTPUT 3 NAME: INST DIFF TRIP 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
As a safety measure, the relay ENTER requires you to enter a new passcode twice. This ensures the passcode has been entered correctly. PLEASE RE-ENTER NEW PASSCODE: GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
It indicates that passcode security is now enabled. ENTER SETPOINT ACCESS IS NOW RESTRICTED After a few seconds, the original display returns. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
When planning the location of your panel cutout, ensure provision is made for the front door to swing open without interference to or from adjacent equipment. Double Panel Single Panel Figure 3–2: SINGLE AND DOUBLE SR RELAY PANEL CUTOUT GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
With the latch raised, pull the center of the handle outward. Once disengaged, continue rotating the handle up to the stop position. PRESS LATCH UP AND PULL ROTATE HANDLE TO STOP HANDLE POSITION 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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As such, a separate seal can be installed on the outside of the door to prevent it from being opened. Figure 3–5: DRAWOUT SEAL GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
The information in this section covers the important aspects of interconnec- tions, in the general areas of instrument transformer inputs, other inputs, outputs, communications, and grounding. 3.2.2 REAR TERMINAL LAYOUT Figure 3–6: REAR TERMINAL LAYOUT 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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PHASE C - WINDING 3 CT SETPOINT ACCESS (–) GROUND - WINDING 1/2 CT LOGIC POWER OUT (+) CONTROL POWER (–) LOGIC POWER OUT (–) CONTROL POWER (+) indicates high side of CT and VT terminals GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
VT is connected to, the power may be negative when the generator is producing positive MWatts. This can be corrected by reversing the voltage input into C11 and C12. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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3 INSTALLATION 3.2 TYPICAL WIRING Figure 3–8: TYPICAL WIRING FOR THREE WINDING TRANSFORMER GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
IMPORTANT: The relay will correctly measure up to 46 times the current input nominal rating. Time over- current curves become horizontal lines for currents above the 46 × CT rating. NOTE 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
+32 V DC Logic Input 1 Logic Input 1 32 V DC 32 V DC 30 to 300 V DC DC Negative DC Negative LOGICIN.CDR Figure 3–10: DRY AND WET CONTACT CONNECTIONS GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
The maximum total resistance the Tap Changer input can measure is 5.1 KΩ. For example, the maximum resistance incre- ment per tap for a 33-position Tap Changer should not exceed 151 Ω. 3-10 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
1 KΩ; for a 0 to 10 mA channel, this resistor would be 500 Ω; and for a 4 to 20 mA channel this resistor would be 250 Ω. Figure 3–12: ANALOG OUTPUT CONNECTION GE Multilin 745 Transformer Management Relay 3-11...
To ensure maximum reliability, all equipment should have similar transient protection devices installed. Figure 3–13: RS485 WIRING 3-12 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
The 745PC software required to use this interface is included with the relay. Cabling for the RS232 port is shown below for both 9 pin and 25 pin connectors. Figure 3–15: RS232 WIRING GE Multilin 745 Transformer Management Relay 3-13...
No special ventilation requirements need to be observed during the installation of the unit. The unit does not have to be cleaned. NOTE Hazard may result if the product is not used for its intended purpose. WARNING 3-14 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Trip and alarm condition messages automatically override default mes- sages. All display pixels are illuminated briefly during power up self-testing, and can be energized by pressing when NEXT no trips or alarms are active. GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
The Message LED indicator is on when any element has picked up, operated, or is now in a latched state waiting to be reset. With this indicator on, the front panel display is sequentially displaying information about each element that has detected an abnormal condition. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
If the display has timed out to the default messages, pressing SETPOINT returns the display to the last viewed setpoint message. The keys move between messages within a MESSAGE MESSAGE page. GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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Note that diagnostic messages for self-resetting targets disappear with the condition, but diagnostic messages for latched targets remain until they are cleared. When no targets are active, illuminates all front panel indicators for approxi- NEXT mately 5 seconds. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Modem Dial Sets the communications parameters Sends the current file to the printer Saves the current file to disk Open an existing file Open a new file Figure 4–2: 745PC TOOLBAR SUMMARY GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
GE Multilin F485 RS232-to-RS485 converter. • A standard “straight through” serial cable connected from your computer to the GE Multilin F485 Converter box. The converter box end should be DB-9 male and the computer end DB-9 or DB-25 female for COM1 or COM2 respectively.
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4.2 745PC SOFTWARE INTERFACE COMPUTER RS232 CONNECTOR COMPUTER COM PORT TYPICALLY COM1 OR COM2 814798A4.CDR Figure 4–4: RS232 COMMUNICATIONS SETUP COMPUTER GE Power Management RS232 to RS485 POWER SUPPLY Converter MODULE TO WALL PLUG 745 rear RS232 CONNECTOR terminal block AB...
Ensure that Windows is running on the local PC. Insert the GE Multilin Products CD into your CD-ROM drive or point your web browser to the GE Multilin website at http://www.GEindustrial.com/multilin. Under Windows 95/98, the Product CD will launch the welcome screen automat- ically.
Startup of the 745PC software is accomplished as follows: Double-click on the 745 software icon inside the GE Multilin group or select from the Windows Start menu to launch 745PC. The 745 to PC communications status is displayed on the bottom right corner of the screen: To configure communications, select the Communication >...
All 745 setpoint files should have the extension .745 (for example, xfrmr01.745). Click OK to proceed. Figure 4–9: SAVING SETPOINTS The software reads all the relay setpoint values and stores them to the selected file. 4-10 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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File names for released 745 firmware have the following format: 33 D 260 A4 .000 Modification Number (000 = none) GE Power Management use only Firmware Revision Required 745 hardware revision Product code (33 = 745 Transformer Mgt. Relay) Figure 4–10: FIRMWARE FILE FORMAT...
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Click the Transformer button in the System Setup window. The following dialog box prompts for the transformer setpoint information. Note that the number of selections shown is dependent on the 745 installed options. Figure 4–12: TRANSFORMER SETPOINTS WINDOW 4-12 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Select a Transformer Type from the drop-down menu. Checked boxes indicate that the user has visited the setpoint during this session. Checked boxes indicate that the user has visited the setpoint during this session. GE Multilin 745 Transformer Management Relay 4-13 Courtesy of NationalSwitchgear.com...
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For example, to view the positive, negative and zero sequence currents in any of the windings click on the Sequence tab. Figure 4–14: ACTUAL VALUES WINDOW 4-14 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
[ENTER] for more MESSAGE HARMONICS ESCAPE See page 5–32. [ENTER] for more MESSAGE FLEXCURVES ESCAPE See page 5–33. [ENTER] for more MESSAGE VOLTAGE INPUT ESCAPE See page 5–33. [ENTER] for more MESSAGE GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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[ENTER] for more MESSAGE HARMONICS ESCAPE See page 5–77. [ENTER] for more MESSAGE INSULATION AGING ESCAPE See page 5–80. [ENTER] for more MESSAGE ANALOG INPUT ESCAPE See page 5–84. [ENTER] for more MESSAGE 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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[ENTER] for more ESCAPE ANALOG OUTPUTS ESCAPE See page 5–94. [ENTER] for more MESSAGE SIMULATION ESCAPE See page 5–95. [ENTER] for more MESSAGE FACTORY SERVICE ESCAPE See page 5–98. [ENTER] for more MESSAGE GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
Passcode protection may also be enabled. When enabled, the 745 requests a numeric passcode before any setpoint can be entered. As an additional safety measure, a minor self-test error is generated when the passcode is entered incorrectly three times in a row. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
WINDING 2 RATED LOAD : "1500:1 A" S2 SYSTEM SETUP WINDING 2 WINDING 2 PHASE CT PRIMARY For a 3-winding transformer, the setpoints under must also be set. S2 SYSTEM SETUP/WINDING 3 GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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: "61.0 kV" MINIMUM TAP POSITION VOLTAGE : "0.50 kV" VOLTAGE INCREMENT PER TAP : "33 Ω" RESISTANCE INCREMENT PER TAP The maximum value resistance on the top tap is 5 kΩ. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
The source phase sequence must be stated when describing the winding phase relationships since these relationships change when the phase sequence changes. The example below shows why this happens, using a transformer described in IEC nomenclature as "Yd1" or in GE Multilin nomenclature as "Y/d30." Figure 5–2: EXAMPLE TRANSFORMER The above figure shows the physical connections within the transformer that produce a phase angle in the delta winding that lags the respective wye winding by 30°.
Note that the Delta winding currents leads the Wye winding currents by 30°, (which is a type Yd11 in IEC nomenclature and a type Y/d330 in GE Multilin nomenclature) which is in disagreement with the transformer nameplate. This is because the physical connections and hence the equations used to calculate current for the delta winding have not changed.
Delta circuit. In both these cases, there is zero-sequence impedance between the primary and secondary windings. The 745 removes zero-sequence current from all Wye/Wye and Wye/Wye/Wye transformer windings to prevent possible relay maloperations resulting from these two conditions. GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
DELTA 300° Y/d210° 210° (gnd 1/2) DELTA 0° 300° lag DELTA 0° 210° lag D/y30° DELTA 0° Y/d330° 330° (gnd 1/2) 330° (gnd 1/2) 30° lag DELTA 0° 330° lag 5-10 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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300° lag ZIG-ZAG 0° (gnd 2/3) 3W External 0° 210° lag Correction (gnd 1/2) Y/z330° 330° (gnd 1/2) 0° (gnd 2/3) 0° ZIG-ZAG 0° (gnd 2/3) 0° 330° lag 0° GE Multilin 745 Transformer Management Relay 5-11 Courtesy of NationalSwitchgear.com...
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0° 210° lag 210° lag Y/y0°/d330° 330° Y/y180°/d330° 330° (gnd 1/2) (gnd 1/2) 330° 150° (gnd 2/3) (gnd 2/3) 0° 180° lag DELTA 0° DELTA 0° 330° lag 330° lag 5-12 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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0° Y/d30°/d150° 30° lag Y/d150°/y180° 150° lag (gnd 1/2) (gnd 1/2) DELTA 0° DELTA 0° 30° lag 150° lag DELTA 240° lag 330° lag 150° lag (gnd 2/3) 180° lag GE Multilin 745 Transformer Management Relay 5-13 Courtesy of NationalSwitchgear.com...
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210° lag Y/d210°/d150° 210° lag Y/d150°/d330° 150° lag (gnd 1/2) (gnd 1/2) DELTA 0° DELTA 0° 210° lag 150° lag DELTA 60° lag DELTA 180° lag 150° lag 330° lag 5-14 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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210° lag 0° Y/d330°/y180° 330° lag Y/d330°/d330° 330° lag (gnd 1/2) (gnd 1/2) DELTA 0° DELTA 0° 330° lag 330° lag 150° lag DELTA 0° (gnd 2/3) 330° lag 180° lag GE Multilin 745 Transformer Management Relay 5-15 Courtesy of NationalSwitchgear.com...
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150° lag (gnd 2/3) 210° lag D/d0°/d240° DELTA 240° lag D/d0°/y330° DELTA 0° DELTA 240° lag 0° DELTA 0° 0° DELTA 0° 240° lag 30° lag (gnd 2/3) 330° lag 5-16 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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150° lag D/d60°/y210° DELTA 0° D/d120°/y330° DELTA 0° DELTA 300° lag DELTA 240° lag 60° lag 120° lag 150° lag (gnd 2/3) 30° lag 210° lag (gnd 2/3) 330° lag GE Multilin 745 Transformer Management Relay 5-17 Courtesy of NationalSwitchgear.com...
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300° lag D/d240°/y30° DELTA 0° D/d180°/y150° DELTA 0° DELTA 120° lag 240° lag DELTA 180° lag 180° lag 330° lag (gnd 2/3) 30° lag 210° lag (gnd 2/3) 150° lag 5-18 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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210° lag (gnd 1/2) 150° lag DELTA 300° lag 60° lag DELTA 240° lag 120° lag D/y30°/d240° DELTA 0° 330° lag (gnd 1/2) 30° lag DELTA 120° lag 240° lag GE Multilin 745 Transformer Management Relay 5-19 Courtesy of NationalSwitchgear.com...
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210° lag 150° lag 330° lag 30° lag (gnd 2/3) (gnd 2/3) 30° lag 330° lag D/y210°/y210° DELTA 0° 150° lag (gnd 1/2) 210° lag 150° lag (gnd 2/3) 210° lag 5-20 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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0° D/y330°/d300° DELTA 0° 30° lag (gnd 1/2) 330° lag DELTA 60° lag 300° lag D/y330°/y150° DELTA 0° 30° lag (gnd 1/2) 330° lag 210° lag (gnd 2/3) 150° lag GE Multilin 745 Transformer Management Relay 5-21 Courtesy of NationalSwitchgear.com...
= (A – B) / 150° lag 330° lag b = (C – B) / b = (B – C) / c = (A – C) / c = (C – A) / 5-22 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
DEFAULT MESSAGE TIMEOUT: After this period of time of no activity on the keys, the 745 automatically begins to display the programmed set of default messages programmed in S1 745 SETUP DEFAULT MESSAGES GE Multilin 745 Transformer Management Relay 5-23 Courtesy of NationalSwitchgear.com...
RS422. • FRONT BAUD RATE / FRONT PARITY: Select the baud rate / parity for the front panel port. These setpoints cannot be changed via the communication ports. 5-24 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Enabling this setpoint will cause the cold restart request to initialize only the DNP sub-module. When “Disabled” is selected, a cold restart request will cause loss of protection until the 745 reset completes. WARNING GE Multilin 745 Transformer Management Relay 5-25 Courtesy of NationalSwitchgear.com...
3:05 PM. ENTER • IRIG-B SIGNAL TYPE: Select the type of IRIG-B signal being used for clock synchronization. Select "None" if no IRIG- B signal is to be used. 5-26 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Text 1 one character at a time, using . Press the key to store the edit and advance to the VALUE VALUE ENTER next character position. This message may then be stored as a default message. GE Multilin 745 Transformer Management Relay 5-27 Courtesy of NationalSwitchgear.com...
745 to upgrade its options. A flash message appears indicating the results of the upgrade. A successful upgrade may be verified by examining the installed options display under A4 PRODUCT INFO REVISION CODES INSTALLED OPTIONS 5-28 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
• PHASE SEQUENCE: Enter the phase sequence of the power system. Systems with an ACB phase sequence require special considerations. See Section 5.2.3: Phase Shifts on Three-Phase Transformers on page 5–7 for details. GE Multilin 745 Transformer Management Relay 5-29...
• WINDING TIME CONST: Required for Insulation Aging calculations • SET ACCUMULATED LOSS OF LIFE: Required for Insulation Aging calculations. Set equal to the estimated accumu- lated loss of life. 5-30 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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This value is normally only available from the transformer manufacturer’s test report, and is used in the 745 for calculation of harmonic derating factor. GE Multilin 745 Transformer Management Relay 5-31 Courtesy of NationalSwitchgear.com...
The harmonic derating factor will only be valid if this information has been entered correctly. 5-32 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
VOLTAGE INPUT PARAMETER: Enter the winding and phase of the voltage connected to the voltage input. • NOMINAL VT SECONDARY VOLTAGE: Enter the nominal secondary voltage (in volts) of the voltage transformer. • VT RATIO: Enter the ratio of the voltage transformer. GE Multilin 745 Transformer Management Relay 5-33 Courtesy of NationalSwitchgear.com...
AVERAGE AMBIENT TEMPERATURE (BY MONTH): This message is displayed only when the AMBIENT RTD TYPE set for "By Monthly Average". Ambient temperature is used in the calculation of Insulation Aging and must be enabled for the function to operate. 5-34 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
ANALOG INPUT RANGE: Select the current output range of the transducer that is connected to the analog input. • ANALOG INPUT MINIMUM/MAXIMUM: Enter the value of the quantity measured which corresponds to the minimum/ maximum output value of the transducer. GE Multilin 745 Transformer Management Relay 5-35 Courtesy of NationalSwitchgear.com...
TIME INTERVAL: This message is displayed only when the is set for “Block Interval” or CURRENT DEMAND METER TYPE “Rolling Demand”. Enter the time period over which the current demand calculation is performed. 5-36 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
ANALOG OUPUT 1(7) RANGE: Select the full-scale range of output current for Analog Output 1(7). • ANALOG OUTPUT 1(7) MIN/MAX: Enter the value of the selected parameter which corresponds to the minimum/ maximum output current of Analog Output 1(7). GE Multilin 745 Transformer Management Relay 5-37 Courtesy of NationalSwitchgear.com...
VALUE VALUE ENTER • INPUT 1 PROGRAMMED STATE: Select "Asserted" to place the virtual input into the signaling state; likewise, select "Not Asserted" to place it into the non-signaling state. 5-38 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Shown as the following schematic symbol: ⊗. • • The exact wording of the front panel label identifies the indicator. LOGIC • Described using basic AND gates and OR gates GE Multilin 745 Transformer Management Relay 5-39 Courtesy of NationalSwitchgear.com...
, which imple- 5TH HARMONIC INHIBIT ments an inhibit scheme based on 5th harmonic only, allowing inhibiting the percent differential during intentional overexci- tation of the system. 5-40 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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NOTE The basic percent differential operating principle for three-winding transformers is illustrated by the following equations: max I restraint differential (EQ 5.4) × --- - %slope 100% GE Multilin 745 Transformer Management Relay 5-41 Courtesy of NationalSwitchgear.com...
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2. The source is connected to one winding only. Therefore, the value cannot be greater than 100%. To increase dependability, PERCENT DIFFERENTIAL SLOPE 2 the Slope 2 settings should be less than 98% 5-42 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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For most transformers, INHIBIT LEVEL the 2 harmonic current alone will exceed 20% during energization and the "2nd" value is sufficient to inhibit the differ- ential element for inrush current. GE Multilin 745 Transformer Management Relay 5-43 Courtesy of NationalSwitchgear.com...
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MESSAGE Range: Logic Input 1 to 16, Disabled BREAKERS ARE OPEN ESCAPE SIGNAL: Disabled MESSAGE Range: Logic Input 1 to 16, Disabled PARALL XFMR BRKR CLS ESCAPE SIGNAL: Disabled MESSAGE 5-44 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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PARALL XFMR BRKR CLS SIGNAL: Select any logic input which, when asserted, will indicate to the 745 the onset of sympathetic inrush. The selected logic input should be connected to the close command going to the parallel trans- former switching device. GE Multilin 745 Transformer Management Relay 5-45...
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5.6 S4 ELEMENTS 5 SETPOINTS Figure 5–10: ENERGIZATION INHIBIT SCHEME LOGIC Figure 5–11: ENERGIZATION SENSING SCHEME LOGIC 5-46 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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• 5th HARMONIC INHIBIT LEVEL: Enter the level of 5th harmonic current above which the percent differential element will be inhibited from operating. Figure 5–12: 5TH HARMONIC INHIBIT SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-47 Courtesy of NationalSwitchgear.com...
INST DIFFERENTIAL PICKUP: Enter the level of differential current (in units of relay nominal current) above which the instantaneous differential element will pickup and operate. Figure 5–13: INSTANTANEOUS DIFFERENTIAL SCHEME LOGIC 5-48 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
TIME OVERCURRENT CURVES The inverse time overcurrent curves used by the TOC (time overcurrent) elements are the ANSI, IEC, and GE Type IAC curve shapes. This allows for simplified coordination with downstream devices. If however, none of these curve shapes is adequate, FlexCurves™...
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T = Operate Time (sec.) M = Multiplier Setting I = Input Current = Pickup Current Setting A to E = Constants pickup Table 5–9: GE TYPE IAC INVERSE TIME CURVE CONSTANTS IAC CURVE SHAPE IAC EXTREME INVERSE 0.0040 0.6379 0.6200 1.7872...
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(as per ANSI / IEEE C57.110-1986) and, when this feature is enabled, automatically shifts the phase time overcurrent curve pickup in order to maintain the required protection margin with respect to the trans- former thermal damage curve, as illustrated below. GE Multilin 745 Transformer Management Relay 5-53...
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Transformer thermal protection margin current Pickup setting based rated load capability Pickup shifted based on harmonic derating Figure 5–14: HARMONIC DERATING CORRECTION Figure 5–15: PHASE TOC SCHEME LOGIC 5-54 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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The setpoint messages above and the following logic diagram are identical for the PHASE INSTANTA- NEOUS OVERCURRENT 2 element. NOTE Figure 5–16: PHASE IOC 1 SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-55 Courtesy of NationalSwitchgear.com...
), which is calculated internally as the vector sum of the three phases. This section contains the settings to configure the neutral overcurrent elements. Included are neutral time overcurrents for each winding, and two levels of neutral instantaneous overcurrent for each winding. 5-56 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Select “Instantaneous” reset to coordinate with relays, such as most static units, with instantaneous reset characteristics. Figure 5–17: NEUTRAL TOC SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-57 Courtesy of NationalSwitchgear.com...
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The setpoint messages above and the following logic diagram are identical for the Neutral Instantaneous Overcurrent 2 element. NOTE Figure 5–18: NEUTRAL IOC 1 SCHEME LOGIC 5-58 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
This section contains the settings to configure the ground overcurrent elements. Included are ground time overcurrents for each (wye or zig-zag) winding, and two levels of ground instantaneous overcurrent for each (wye or zig-zag) winding. GE Multilin 745 Transformer Management Relay 5-59...
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W1(3) GROUND TIME OC RESET: Enter the multiplier constant by which the selected time overcurrent curve shape (the base curve) is to be shifted in time. Figure 5–19: GROUND TOC SCHEME LOGIC 5-60 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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The messages above and scheme logic below are identical for Windings 2 and 3 of Ground Instantaneous Overcurrent 1 and all windings on the Ground Instantaneous Overcurrent 2 element. NOTE Figure 5–20: GROUND IOC 1 SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-61 Courtesy of NationalSwitchgear.com...
Therefore, the resultant differential currents could be below the slope threshold of the per- cent differential element and thus the fault could go undetected. The graph below shows the relationship between the pri- 5-62 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Maximum Phase Slope = Igd/Imax Current Slope > Setpoint Calculate Timer OUTPUT 0 to 0.5 s Calculate Igd > Setpoint |3I – Ig| Measure Figure 5–25: RESTRICTED GROUND FAULT IMPLEMENTATION GE Multilin 745 Transformer Management Relay 5-63 Courtesy of NationalSwitchgear.com...
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W1(3) RESTD GND FAULT DELAY: Enter the time that the Winding 1(3) Restricted Ground Fault element must remain picked up before the element operates. Figure 5–26: RESTRICTED GROUND FAULT SCHEME LOGIC 5-64 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
MESSAGE This section contains the settings to configure the negative sequence overcurrent elements. Included are negative sequence time overcurrents for each winding, and negative sequence instantaneous overcurrents for each winding. GE Multilin 745 Transformer Management Relay 5-65 Courtesy of NationalSwitchgear.com...
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“energy” accumulated to that required to trip. Select Instantaneous reset to coordinate with relays, such as most static units, with instantaneous reset characteristics. Figure 5–27: NEGATIVE SEQUENCE TOC SCHEME LOGIC 5-66 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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W1(3) NEG SEQ INST OC DELAY: Enter the time that the negative sequence current must remain above the pickup level before the element operates. Figure 5–28: NEGATIVE SEQUENCE IOC SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-67 Courtesy of NationalSwitchgear.com...
Range: Logc Inpt 1 to 16, Virt Inpt 1 to 16, Output Rly 2 to UNDERFREQUENCY 1 ESCAPE 8, SelfTest Rly, Vir Outpt 1 to 5, Disabled BLOCK: Disabled MESSAGE 5-68 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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• UNDERFREQUENCY 1(2) DELAY: Enter the time the frequency remains below the pickup level before element oper- ation. Figure 5–29: UNDERFREQUENCY 1 SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-69 Courtesy of NationalSwitchgear.com...
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FREQUENCY DECAY THRESHOLD: Enter the frequency (in Hz) below which the four frequency rate-of-change lev- els of the frequency decay element will be allowed to operate. • FREQUENCY DECAY RATE 1(4): Enter the rate of frequency decay beyond which the corresponding element oper- ates. 5-70 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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MESSAGE Range: Logc Inpt 1 to 16, Virt Inpt 1 to 16, Output Rly 2 to OVERFREQUENCY ESCAPE 8, SelfTest Rly, Vir Outpt 1 to 5, Disabled BLOCK: Disabled MESSAGE GE Multilin 745 Transformer Management Relay 5-71 Courtesy of NationalSwitchgear.com...
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OVERFREQUENCY PICKUP: Enter the frequency (in Hz) above which the overfrequency element will pickup and start the delay timer. • OVERFREQUENCY DELAY: Enter the time that the frequency must remain above the pickup level before the element operates. Figure 5–31: OVERFREQUENCY SCHEME LOGIC 5-72 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
A significant amount of current at the 5th harmonic is characteristic of overexcitation. This section contains the settings to configure the overexcitation monitoring elements. Included are a 5th harmonic level, and two volts-per-hertz elements, each with a pickup level and a time delay. GE Multilin 745 Transformer Management Relay 5-73...
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• 5TH HARMONIC LEVEL DELAY: Enter the time that the 5th harmonic current must remain above the pickup level before the element operates. Figure 5–32: 5TH HARMONIC LEVEL SCHEME LOGIC 5-74 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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VOLTS-PER-HERTZ 1 DELAY: Enter the time that the volts-per-hertz value must remain above the pickup level before the element operates. • VOLTS-PER-HERTZ 1 RESET: Enter the time that the volts-per-hertz value must remain below the pickup level before the element resets. GE Multilin 745 Transformer Management Relay 5-75 Courtesy of NationalSwitchgear.com...
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V = fundamental RMS value of voltage (V) F = frequency of voltage signal (Hz) Pickup = volts-per-hertz pickup setpoint (V/Hz) 1.00 1.20 1.40 1.60 1.80 2.00 Multiples of Voltz/Hertz Pickup 5-76 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
See page 5–79. [ENTER] for more MESSAGE This section contains the settings to configure the total harmonic distortion monitoring elements. Included are a THD level element for each winding and each phase. GE Multilin 745 Transformer Management Relay 5-77 Courtesy of NationalSwitchgear.com...
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Distortion element level will pickup and start the delay timer. • W1(3) THD LEVEL DELAY: Enter the time that the total harmonic distortion must remain above the pickup level before the element operates. Figure 5–34: THD LEVEL SCHEME LOGIC 5-78 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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• W1(3) HARMONIC DERATING DELAY: Enter the time that the harmonic derating must remain below the pickup level before the element operates. Figure 5–35: HARMONIC DERATING SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-79 Courtesy of NationalSwitchgear.com...
The preferred approach for ambient temperature is to use an RTD connected to the 745. If this is not feasible, average val- ues for each month of the year can be entered as settings, under S2 SYSTEM SETUP AMBIENT TEMPERATURE AMBI- and selecting By Monthly Average. ENT RTD TYPE 5-80 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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• HOTTEST SPOT LIMIT DELAY: Enter a time delay above which the hottest-spot temperature must remain before the element operates. Figure 5–36: HOTTEST-SPOT LIMIT SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-81 Courtesy of NationalSwitchgear.com...
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• AGING FACTOR LIMIT DELAY: Enter a time delay above which the Aging Factor must remain before the element operates. Figure 5–37: AGING FACTOR LIMIT SCHEME LOGIC 5-82 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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10 = 131400. × The actual values are only displayed if the Loss of Life option is installed and the ambient temperature is enabled. NOTE Figure 5–38: LOSS-OF-LIFE SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-83 Courtesy of NationalSwitchgear.com...
The analog input is configured in S2 SYSTEM SETUP ANALOG INPUT the actual values displayed in A2 METERING ANALOG INPUT Figure 5–39: ANALOG LEVEL SCHEME LOGIC 5-84 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
This section contains the settings to configure the current demand monitoring elements. Included are a current demand level for each winding and each phase. Figure 5–40: CURRENT DEMAND SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-85 Courtesy of NationalSwitchgear.com...
XFMR OVERTEMP ALARM SIGNAL: Select any logic input that, when asserted, indicates the transformer cooling system has failed and an over-temperature condition exists. The logic input should be connected to the transformer winding temperature alarm contacts. Figure 5–41: TRANSFORMER OVERLOAD SCHEME LOGIC 5-86 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Setpoint group for the Harmonic Restrained Differential element, assuming that the tap changer position was used to compensate the input current magnitude. Figure 5–42: TAP CHANGER FAILURE SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-87...
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The timer runs to completion (i.e. the ‘start’ condition is met for the programmed time delay) * element refers to any protection or monitoring element programmed under page S4 ELEMENTS 5-88 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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AND gate. The inputs of the 2-input AND gate are the output of the NOT gate, and Output Relay 2. The input to the NOT gate is Logic Input 2. The inputs to the 2-input XOR gate are Virtual Output 1 and Logic Input 1. For all these gates, the inputs precede the gate itself. GE Multilin 745 Transformer Management Relay 5-89...
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(Output 1) remains closed until externally reset by a momentary interruption of current, unless wired in parallel with an electromechanical relay (Outputs 2 to 8) in which case it turns off when the relay operates. 5-90 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Xfmr Overload OP OR (2 inputs) OR (2 inputs) Any W2 OC OP 5th HarmLevel OP OR (4 inputs) OR (4 inputs) 06 to 20 Figure 5–45: OUTPUT RELAYS SCHEME LOGIC GE Multilin 745 Transformer Management Relay 5-91 Courtesy of NationalSwitchgear.com...
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This section contains the settings (including the FlexLogic™ equation) to configure trace memory triggering. • NO. OF PRE-TRIGGER CYCLES: Enter the number of cycles of data, of the 16 cycles of waveform data to be cap- tured, that are to be pre-trigger information. 5-92 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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• TIMER 1(10) DROPOUT DELAY: Enter the delay time after which the start condition for Timer 1(10) must remain not operated or not asserted, before the timer will stop operating. GE Multilin 745 Transformer Management Relay 5-93 Courtesy of NationalSwitchgear.com...
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4 to 20 mA, entering 100% outputs 20 mA, 0% outputs 4 mA, and 50% outputs 12 mA. This setpoint is only operational if analog output testing is enabled. 5-94 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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• START PLAYBACK MODE SIGNAL: Select any logic input which, when asserted, initiates Playback Mode simulation. This signal has an effect only if the 745 is initially in Prefault Mode. GE Multilin 745 Transformer Management Relay 5-95 Courtesy of NationalSwitchgear.com...
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Range: 0 to 359° in steps of 1 W3 PHASE A CURRENT ESCAPE ANGLE: 0° MESSAGE Range: 0 to 359° in steps of 1 W1 PHASE B CURRENT ESCAPE ANGLE: 0° MESSAGE 5-96 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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• W1(3) GROUND CURRENT ANGLE: Enter the Winding 1(3) ground current angle (with respect to the Winding 1 Phase A current phasor). This message only appears for wye or zig-zag connected windings. GE Multilin 745 Transformer Management Relay 5-97 Courtesy of NationalSwitchgear.com...
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This section contains settings intended for factory use only, for calibration, testing, and diagnostics. The messages can only be accessed by entering a factory service passcode in the first message. 5-98 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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MESSAGE ANALOG INPUT ESCAPE See page 6–12. [ENTER] for more MESSAGE POWER ESCAPE See page 6–12. [ENTER] for more MESSAGE ENERGY ESCAPE See page 6–13. [ENTER] for more MESSAGE ESCAPE MESSAGE GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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(as selected by setpoints) or the options installed in the relay during manu- facture. For example, no display associated with Winding 3 will ever appear if the relay is not configured for three-winding operation. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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STATE: De-energized ESCAPE ↓ OUTPUT RELAY 8 ESCAPE STATE: De-energized MESSAGE SELF-TEST RELAY ESCAPE STATE: Energized MESSAGE The states of Output Relays 1 through 8 and the Self-Test Relay are displayed here. GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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FlexLogic™ equation. The FLEXLOGIC EQN EDITOR BAD SETTINGS value displays the cause of a bad setting made while assigning setpoint values. ERROR 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Phase A is always set to 0° as it is used as reference for all other currents, both measured and derived. The maximum specified load and average phase current are also shown for the specified winding. GE Multilin 745 Transformer Management Relay...
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0 A at 0° Lag MESSAGE W3 ZERO SEQ CURRENT: ESCAPE 0 A at 0° Lag MESSAGE The zero-sequence current magnitudes and phase values for Windings 1, 2, and 3 are shown here. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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W2 GND DIFFERENTIAL ESCAPE CURRENT: 0.00 x CT MESSAGE W3 GND DIFFERENTIAL ESCAPE CURRENT: 0.00 x CT MESSAGE The ground differential current magnitudes for Windings 1 through 3 are shown here. GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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(in this case the second harmonic). Similar displays exist for all harmonics up to the 21 The second harmonic magnitude for each phase current of Windings 1 through 3 are displayed. Values are expressed as a percentage of magnitude of the corresponding fundamental frequency component. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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The Harmonic Derating Factor for each of the windings shows the effect of non-sinusoidal load currents on power trans- former’s rated full load current. The calculations are based on ANSI/IEEE standard C57.110-1986. The actual values mes- sages display the harmonic derating factor for Windings 1 through 3. GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
6.3.7 AMBIENT TEMPERATURE PATH: ACTUAL VALUES A2 METERING AMBIENT TEMPERATURE ð AMBIENT TEMP AMBIENT TEMPERATURE: ENTER [ENTER] for more 0°C ESCAPE Ambient temperature is monitored via an RTD connected to the 745. GE Multilin 745 Transformer Management Relay 6-11 Courtesy of NationalSwitchgear.com...
Power flowing into the power transformer is designated as source power and power flowing out of the transformer is designated as load power. The messages above are repeated for Windings 2 and 3. 6-12 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
0 Mvarh MESSAGE W1 LOAD VARHOURS: ESCAPE 0 Mvarh MESSAGE The source and load watthours and varhours are displayed for Winding 1. These messages are repeated for Windings 2 and 3. GE Multilin 745 Transformer Management Relay 6-13 Courtesy of NationalSwitchgear.com...
W2 PHASE A CURRENT ESCAPE 0 A at 0° Lag MESSAGE W2 PHASE B CURRENT ESCAPE 0 A at 0° Lag MESSAGE W2 PHASE C CURRENT ESCAPE 0 A at 0° Lag MESSAGE 6-14 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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MESSAGE FREQUENCY DECAY ESCAPE RATE: 0.00 Hz/s MESSAGE TAP CHANGER ESCAPE POSITION: n/a MESSAGE VOLTS-PER-HERTZ: ESCAPE 0.00 V/Hz MESSAGE AMBIENT TEMPERATURE: ESCAPE 0°C MESSAGE ANALOG INPUT: ESCAPE 0 µA MESSAGE GE Multilin 745 Transformer Management Relay 6-15 Courtesy of NationalSwitchgear.com...
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Bad Xfmr Settings IRIG-B Signal Setpt Access Denied Ambnt temperature The recorded event displayed for Logic inputs, Virtual Inputs, and Relay outputs will show the programmed name of the input/output. NOTE 6-16 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
6 ACTUAL VALUES 6.5 A4 PRODUCT INFO 6.5A4 PRODUCT INFO 6.5.1 TECHNICAL SUPPORT PATH: ACTUAL VALUES A4 PRODUCT INFO TECHNICAL SUPPORT ð TECHNICAL SUPPORT GE Multilin ENTER [ENTER] for more 215 Anderson Avenue ESCAPE Markham, Ontario, ESCAPE Canada, L6E 1B3 MESSAGE...
W3 Harmonic Derating Analog Level 1 Analog Level 2 W1 Current Demand W2 Current Demand W3 Current Demand Xformer Overload Logic Input 1 (to 16) Virtual Input 1 (to 16) 6-18 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Self-Test Error LED • de-energizes the Self-Test Relay • indicates the failure by inserting an appropriate message in the target message queue • records the failure in the Event Recorder GE Multilin 745 Transformer Management Relay 6-19 Courtesy of NationalSwitchgear.com...
This flash message is displayed in response to pressing the decimal key, followed by DEFAULT MESSAGE twice, on one of the selected default messages in the subgroup S1 745 SETUP HAS BEEN REMOVED ENTER DEFAULT MESSAGES 6-20 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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This flash message is displayed in response to pressing while on any setpoint SETPOINT ACCESS ENTER message. Setpoint access is restricted because the programmed passcode has not DENIED (PASSCODE) been entered to allow access. GE Multilin 745 Transformer Management Relay 6-21 Courtesy of NationalSwitchgear.com...
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745 detects an invalid serial number. NUMBER This flash message is displayed when an attempt to upgrade an option was success- PASSCODE VALID - ful. OPTIONS ADJUSTED 6-22 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
7 COMMUNICATIONS 7.1OVERVIEW 7.1.1 PROTOCOLS The GE Multilin 745 Transformer Management Relay communicates with other computerized equipment such as program- mable logic controllers, personal computers, or plant master computers using either the AEG Modicon Modbus protocol or the Harris Distributed Network Protocol (DNP), Version 3.0. Following are some general notes: •...
7.2.4 DATA FRAME FORMAT AND DATA RATE One data frame of an asynchronous transmission to or from a GE Multilin 745 consists of 1 start bit, 8 data bits, and 1 stop bit. This produces a 10 bit data frame. The 745 can be configured to include an additional even or odd parity bit if required, producing an 11 bit data frame.
• FUNCTION CODE: This is the second byte of every message. Modbus defines function codes of 1 to 127. The GE Multilin 745 implements some of these functions. In a master query message the Function Code tells the slave what action to perform.
No: go to 3. Yes: continue. A --> CRC GE Multilin will provide a C programming language implementation of this algorithm upon request. NOTE 7.2.7 MESSAGE TIMING Communication message synchronization is maintained by timing constraints. The receiving device must measure the time between the reception of characters.
7.3.1 SUPPORTED MODBUS FUNCTIONS a) DESCRIPTION The second byte of every message is the function code. Modbus defines function codes of 01h to 7Fh. The GE Multilin SR Series Modbus protocol supports some of these functions, as summarized below. Table 7–1: GE MULTILIN MODBUS FUNCTION CODES...
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FUNCTION CODE 05H: EXECUTE OPERATION Modbus implementation: Force Single Coil GE Multilin implementation: Execute Operation This function code allows the master to perform various operations in the 745. The 2 byte Code Value of FF00h must be sent after the Operation Code for the operation to be performed.
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FUNCTION CODE 06H: STORE SINGLE SETPOINT Modbus Implementation: Preset Single Register GE Multilin Implementation: Store Single Setpoint This function code allows the master to modify the contents of a single setpoint register in the addressed slave device. The response of the slave device to this function code is an echo of the entire master query message.
An external device connected to the addressed slave device has failed and the data DEVICE requested cannot be sent. This response will be returned if a GE Multilin device connected to the RS485 external device port of the 745 has failed to respond to the 745.
User Map Value #2 the value at User Map Address #2, and so on. Writing to any User Map Value is only possible if the address stored in the corresponding User Map Address is that of a setpoint value. GE Multilin 745 Transformer Management Relay...
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Percent Differential Pickup = 0.30 × I DATA #6: high order byte, low order byte 00 1E CRC: low order byte, high order byte 80 F1 CRC computed by slave 7-10 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
NUMBER OF SETPOINTS: high order byte, low order byte 00 01 1 setpoint values = 2 bytes total CRC: low order byte, high order byte 02 31 CRC computed by slave GE Multilin 745 Transformer Management Relay 7-11 Courtesy of NationalSwitchgear.com...
2000 to 3FFF Read and write. Trace Memory 4000 to 47FF Read only (except "Trace Buffer Selector Index" and "Trace Channel Selector Index") Playback Memory 4800 to 4FFF Read and write. 7-12 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
FORMAT FACTORY (HEX) VALUE CODE DEFAULT Product ID (Addresses 0000 to 007F) - Read Only PRODUCT ID 0000 GE Product Device Code 33 = 745 0001 Hardware Revision 4 = D 0002 Software Revision 0003 Version Number 000 to 999...
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Winding 3 Ground Time O/C Flag 0223 Winding 1 Ground Inst O/C 1 Flag 0224 Winding 2 Ground Inst O/C 1 Flag 0225 Winding 3 Ground Inst O/C 1 Flag 7-14 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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0 to 359 ° Lag 02BA Winding 3 Negative Sequence Current Mag 02BB Winding 3 Negative Sequence Current Angle 0 to 359 ° Lag 02BC Winding 1 Zero Sequence Current Magnitude 7-16 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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0.0 to 99.9 % ƒo 0306 Winding 3 Phase A 4th Harmonic Content 0.0 to 99.9 % ƒo 0307 Winding 3 Phase B 4th Harmonic Content 0.0 to 99.9 % ƒo GE Multilin 745 Transformer Management Relay 7-17 Courtesy of NationalSwitchgear.com...
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0.0 to 99.9 % ƒo HARMONIC 0351 Winding 1 Phase B 9th Harmonic Content 0.0 to 99.9 % ƒo 0352 Winding 1 Phase C 9th Harmonic Content 0.0 to 99.9 % ƒo 7-18 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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% ƒo 0397 Winding 3 Phase B 13th Harmonic Content 0.0 to 99.9 % ƒo 0398 Winding 3 Phase C 13th Harmonic Content 0.0 to 99.9 % ƒo 0399 Reserved GE Multilin 745 Transformer Management Relay 7-19 Courtesy of NationalSwitchgear.com...
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0.0 to 99.9 % ƒo 03E3 Winding 2 Phase A 18th Harmonic Content 0.0 to 99.9 % ƒo 03E4 Winding 2 Phase B 18th Harmonic Content 0.0 to 99.9 % ƒo 7-20 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Winding 3 Phase B Total Harmonic Distortion 0.0 to 99.9 % ƒo 0428 Winding 3 Phase C Total Harmonic Distortion 0.0 to 99.9 % ƒo 0429 Reserved ↓ ↓ ↓ ↓ ↓ ↓ ↓ 042F Reserved GE Multilin 745 Transformer Management Relay 7-21 Courtesy of NationalSwitchgear.com...
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↓ 047F Reserved LOSS-OF-LIFE 0480 Hottest-spot Winding Temperature –50 to 300 °C 0481 Total Accumulated Loss-of-Life (2 registers) 0 to 200000 hours 0 hours 0483 Aging Factor 0.0 to 2000.0 7-22 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Maximum Event Winding 3 Phase A Current 0819 Maximum Event Winding 3 Phase B Current 081A Maximum Event Winding 3 Phase C Current 081B Maximum Event Winding 3 Ground Current GE Multilin 745 Transformer Management Relay 7-23 Courtesy of NationalSwitchgear.com...
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0.00 to 655.35 0.01 × CT 0.00 × CT 0864 Event XX Phase C Restraint Current 0.00 to 655.35 0.01 0865 Event XX System Frequency 0.00 to 99.99 0.01 0.00 Hz 7-24 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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1 to 20000 220.0 kV 1121 Winding 1 Rated Load 1 to 20000 1000 = 100 MVA 1122 Winding 1 Phase CT Primary 1 to 50000 :1 or :5 A 500 A 7-26 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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0 to 65000 0 ms FlexCurve A Delay at 2.70 × PKP 1182 0 to 65000 0 ms FlexCurve A Delay at 2.80 × PKP 1183 0 to 65000 0 ms GE Multilin 745 Transformer Management Relay 7-27 Courtesy of NationalSwitchgear.com...
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0 to 65000 0 ms FlexCurve A Delay at 17.0 × PKP 11B9 0 to 65000 0 ms FlexCurve A Delay at 17.5 × PKP 11BA 0 to 65000 0 ms 7-28 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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12D3 Analog Output 1 Minimum 12D4 Analog Output 1 Maximum 1000 A 12D5 Analog Output 2 Function 0 = Disabled 12D6 Analog Output 2 Value 1 = W1 øB curr GE Multilin 745 Transformer Management Relay 7-29 Courtesy of NationalSwitchgear.com...
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1 = Closed 134D Logic Input 8 Function 0 = Disabled 134E Logic Input 8 Name (9 registers) "Logic Input 8" 1357 Logic Input 8 Asserted State 1 = Closed 7-30 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Virtual Input 6 Name (9 registers) "Virtual Input 6" 13FC Virtual Input 7 Function 0 = Disabled 13FD Virtual Input 7 Name (9 registers) "Virtual Input 7" 1406 Virtual Input 8 Function 0 = Disabled GE Multilin 745 Transformer Management Relay 7-31 Courtesy of NationalSwitchgear.com...
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0 = End 1D81 Timer 1 Pickup Delay 0.00 to 600.00 0.01 0.00 s 1D82 Timer 1 Dropout Delay 0.00 to 600.00 0.01 0.00 s 1D83 Timer 2 Start 0 = End GE Multilin 745 Transformer Management Relay 7-33 Courtesy of NationalSwitchgear.com...
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0 to 100 1E16 Force Analog Output 6 0 to 100 1E17 Force Analog Output 7 0 to 100 1E18 Reserved ↓ ↓ ↓ ↓ ↓ ↓ ↓ 1E1F Reserved 7-34 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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20 = 2.0 × CT 2004 Percent Differential Break Point 1.0 to 20.0 2005 Percent Differential Slope 2 50 to 100 100% 2006 Percent Differential Block 0 = Disabled 2007 Reserved GE Multilin 745 Transformer Management Relay 7-35 Courtesy of NationalSwitchgear.com...
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Format: Signed value Example: 1234 stored as 1234 0000 0000 0001 0101 19 = 21st For CT PRIMARY > 2000 A Format: Signed value, scaled by 10 Example: 12340 stored as 1234 GE Multilin 745 Transformer Management Relay 7-59 Courtesy of NationalSwitchgear.com...
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Unsigned Value, 2 Decimal Places Example: 12.34 stored as 1234) F102 16 bits DATA LINK CONFIRMATION MODE 0000 0000 0000 0000 0=Never 0000 0000 0000 0001 1=Sometimes 0000 0000 0000 0010 2=Always 7-60 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Sometimes Configurable (For an explanation of the above, refer to the discussion accompanying Binary Output/Control Relay Output point list) Queue Never Always Sometimes Configurable Clear Queue Never Always Sometimes Configurable GE Multilin 745 Transformer Management Relay 7-61 Courtesy of NationalSwitchgear.com...
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The data link layer confirmation mode, confirmation timeout, and number of retries are all configurable. Refer to the setpoints defined under for more details (refer to Section 5.3.4: DNP Communications on page S1 745 SETUP 5–25.) 7-62 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
The point tables for Binary Input and Analog Input objects contain a field which defines to which event class the corre- sponding static data has been assigned. For this object, the qualifier code must specify an index of 7 only. GE Multilin 745 Transformer Management Relay 7-63...
Class 1 Note 1 Setpoint Group 4 Active Class 1 Note 1 Notes: Any detected change in the state of any point will cause the generation of an event object. 7-64 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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When using object 10 to read the status of a Binary Output, a read of point 0 will always return zero. For other points, the current state of the corresponding Virtual Input will be returned. GE Multilin 745 Transformer Management Relay 7-65 Courtesy of NationalSwitchgear.com...
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Winding 1 Negative Sequence Current Magnitude Class 1 Note 6 Winding 2 Negative Sequence Current Magnitude Class 1 Note 7 Winding 3 Negative Sequence Current Magnitude Class 1 Notes 5,8 7-66 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Winding 3 Real Power Class 1 Note 5,8 Winding 3 Reactive Power Class 1 Note 5,8 Winding 3 Apparent Power Class 1 Note 5,8 Winding 3 Power Factor Class 1 Note 5 GE Multilin 745 Transformer Management Relay 7-67 Courtesy of NationalSwitchgear.com...
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Refer to the section in this chapter titled Accessing Data Via The User Map for more information. Please note that changes in User Map Values never generate event objects. 7-68 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Differential, which will almost always be enabled. If, for some reasons, this element is not enabled when the relay is in service, you will need to test the Local/Remote Reset when testing another protection element. GE Multilin 745 Transformer Management Relay...
• The ground current is the current signal measured by means of a CT in the power transformer connection to ground. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
With only I connected (with a return path) the pickup level of any element can be measured. Figure 8–1: TEST SETUP GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
It is necessary to keep track of modifications/changes made to settings during the course of these com- missioning steps and ensure that all settings are returned to the "in-service" values at the end of the tests, prior to placing the relay into service. CAUTION 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Low voltage inputs (< 30 V) such as RTDs, analog inputs, analog outputs, digital inputs, and RS485 communication ports are not to be tested for dielectric strength under any circumstance. GE Power Management Figure 8–2: TESTING FOR DIELECTRIC STRENGTH...
Now return all output forcing to "De-energized" and disable the relay forcing function by setting S6 TESTING OUTPUT to "Disabled" RELAYS FORCE OUTPUT RELAYS FUNCTION All the output relays should reset. 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Now, lower the current amplitude while displaying the system frequency. Verify that the frequency is displayed correctly with current levels down to approximately 50 mA rms input. Decrease current to 0 A. GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
Table 5–1: Transformer Types on page 5–10 shows that the Y-side currents are shifted by 30° to match the Delta secondary side. The 30° phase shift is obtained from the equations below: 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Compare the displayed value of temperature against known temperature at the location of the sensor. Use a thermom- eter or other means of obtaining actual temperature. An alternative approach is to perform a more detailed calibration per the procedure outlined below. GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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A2 METERING AMBIENT TEMP AMBIENT TEMPERATURE ature. Verify that values entered for other months do not affect the value for the present month. 8-10 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Adjust the resistance to simulate the minimum tap position and verify that a "1" is displayed. Now gradually increase the resistance up to the value which represents the maximum tap value, verifying that the tap position indicator tracks the resistance. GE Multilin 745 Transformer Management Relay 8-11...
The above tests have effectively verified the minimum operating level of the three harmonic restrained differential elements. If desired the above measurements may be repeated for the phase inputs for the other winding(s). The results should be identical. 8-12 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Close the switch and set the current level to 3 times the minimum pickup value measured earlier. Re-open the switch and reset all targets on the relay. Ensure that timer circuit functions correctly. GE Multilin 745 Transformer Management Relay 8-13...
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This is caused by the current values moving into the slope 2 region. Continue increasing I until the element operates again. Compute the slope 2 value at this point. 8-14 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Connect the test setup as below to supply the Phase A element. Set the fundamental current level to the CT rated sec- ondary value. The harmonic restraint differential element of Phase A should be operated. GE Multilin 745 Transformer Management Relay 8-15 Courtesy of NationalSwitchgear.com...
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Apply current to operate the differential element then assert Logic Input 1. Verify that the element has reset and that all targets can be reset. With Logic Input 1 asserted, remove the current and reapply. Verify that the element did not operate. 8-16 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
The settings for these elements are found in the setpoints page. S4 ELEMENTS PHASE OC GE Multilin 745 Transformer Management Relay 8-17 Courtesy of NationalSwitchgear.com...
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A precise measurement of the reset time requires a relay test set capable of dynamic operation, with three sequenced stages, each with programmable current levels and time duration external contact, and flexible triggering. To perform such a test, please contact GE Multilin for detailed test instructions. 8-18...
Phases B and C of Winding 1. For Phase B, X = H2 and Y = G2. For Phase C, X = H3 and Y = G3. The displayed message should change to indicate the correct phase, winding, and element that operated. GE Multilin 745 Transformer Management Relay 8-19 Courtesy of NationalSwitchgear.com...
Trip and Message LEDs should remain on if the was selected as "Latched". W1 NEUTRAL TIME OC TARGET Otherwise only the Trip LED remains on. Reset indicators and clear messages. 8-20 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
A precise measurement of the reset time requires a relay test set capable of dynamic operation, with three sequenced stages, each with programmable current levels and time duration, and flexible external contact triggering. To perform such a test, contact GE Multilin for detailed test instructions. A simple verification of the reset mode selected by...
This reset level for the cur- rent should be approximately 98% of the pickup level. Once the relay drops out, slowly increase the current until the 8-22 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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A precise measurement of the reset time requires a relay test set capable of dynamic operation, with three sequenced stages, each with programmable current levels and time duration, and flexible external contact triggering. To perform such a test, contact GE Multilin for detailed test instructions. A simple verification of the reset mode selected with the...
Disable all protection features except Ground IOC 2. Make the appropriate changes for the display indications and output relays operated by the Ground IOC 2 elements. 8-24 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
WINDING 1 ELEMENT: To ensure that only the Restricted Ground Fault element operates the trip relays (and any other output relays selected by the logic) disable all protection features except Restricted Ground Fault. GE Multilin 745 Transformer Management Relay 8-25...
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Calculate the slope at this point. Decrease the slope setting to 0% then continue to increase the I current until the element resets. Slowly increase I until the element operates again. 8-26 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Trip and Message LEDs should remain on if the was selected as "Latched". W1 NEG SEQ TIME OC TARGET Otherwise only the Trip LED remains on. Reset indicators and clear messages. GE Multilin 745 Transformer Management Relay 8-27 Courtesy of NationalSwitchgear.com...
W1 NEG SEQ INST OC PICKUP With current applied to a single phase, the negative sequence current component is calculated from: × NOTE -- - (EQ 8.15) neg seq phase 8-28 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
As a preliminary step, disable all protection functions except Underfrequency 1. Verify that settings match the in-service requirements. Settings are entered or modified in the settings menu. S4 ELEMENTS FREQUENCY UNDERFREQUENCY 1 GE Multilin 745 Transformer Management Relay 8-29 Courtesy of NationalSwitchgear.com...
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60.00 Hz (or 50.00 Hz) and the amplitude to the rated CT secondary current. Monitor the appropriate trip and auxiliary relays. Reset all alarms and indications. The display should remain unchanged with no trip indications. 8-30 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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Slowly increase the frequency until the output relay(s) operate. Check that the frequency at which operation took place is the selected frequency setting. As the frequency is varied, verify that the A2 METERING FREQUENCY SYSTEM actual value indicates the correct value of system frequency. FREQUENCY GE Multilin 745 Transformer Management Relay 8-31 Courtesy of NationalSwitchgear.com...
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0.03 Hz. Check that the Trip LED is still on. The trip message stays on if the OVERFRE- setting is "Latched"; if it is "Self-resetting", the message resets when frequency is below the setpoint. QUENCY TARGET 8-32 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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A high-quality programmable function generator is required to verify this element. Since the frequency rates of change are measured over a narrow range, the test instrumentation must accurately simulate frequency decay rates without any significant jitter. It is the experience of GE Multilin that some commercial dedicated relay test NOTE equipment with built-in frequency ramping functions is not accurate enough to verify the 745 performance.
This test requires a current generator capable of producing a fundamental and 5th harmonic component. Connect the current signal to H1 and G1 and set the fundamental component level above the threshold setting. 8-34 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
Calculate that the resistance at which the element operated is 150% of the resistance that would be present at the maximum tap position. Verify all relay, targets and messages for correct operation per programmed values. GE Multilin 745 Transformer Management Relay 8-35...
. These values represent the fundamental component only. CAUTION RENT OTHER THD ELEMENTS: A THD element can be programmed for each winding of the transformer. Use the above procedure to verify the element(s) on the other winding(s). 8-36 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
S4 ELEMENTS XFORMER OVERLOAD TRANSFORMER OVERLOAD DELAY The blocking from logic input, if enabled, can be tested as described in earlier tests for other elements. NOTE GE Multilin 745 Transformer Management Relay 8-37 Courtesy of NationalSwitchgear.com...
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Energize the relay power supply and verify that the Relay In Service LED is ON, and that the Self-Test Error LED is OFF, establishing that the relay is operating normally. 8-38 745 Transformer Management Relay GE Multilin Courtesy of NationalSwitchgear.com...
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First Year of Manufacture: 1998 I the undersigned, hereby declare that the equipment specified above conforms to the above Directives and Standards Full Name: John Saunders Position: Manufacturing Manager Signature: Place: GE Multilin Date: 1998 GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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24 months from date of ship- ment from factory. In the event of a failure covered by warranty, GE Multilin will undertake to repair or replace the relay providing the warrantor determined that it is defective and it is returned with all transportation charges prepaid to an authorized service centre or the factory.
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..............5-89, 5-90 ..............6-11 actual values ................5-89 gates ................ 5-85 setpoints ..............5-88 input types CURRENT METERING ......... 6-5, 6-6, 6-7 ..............5-88 introduction ..............5-88 output types GE Multilin 745 Transformer Management Relay Courtesy of NationalSwitchgear.com...
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