GE 745 TRANSFORMER MANAGEMENT RELAY User manual

745
TRANSFORMER MANAGEMENT RELAY™
INSTRUCTION MANUAL
Firmware Revision: 250.000
Manual P/N: 1601-0070-B2 (GEK-106292)
Copyright © 2001 GE Power Management
GE Power Management
215 Anderson Avenue, Markham, Ontario
Canada L6E 1B3
Tel: [phone] Fax: [phone]
Internet: http://www.GEindustrial.com/pm Manufactured under an
ISO9001 Registered system.
g
GE Power Management
745 Transformer Management Relay ™
814768AF.CDR
IN SERVICE
LOCAL
SETPOINT GROUP 2
LOAD-LIMIT
REDUCED
TRIP
SELF-TEST
ERROR
SETPOINT GROUP 3
TRANSFORMER
DE-ENERGIZED
ALARM
PICKUP
TEST MODE
TRANSFORMER
OVERLOAD
SETPOINT GROUP 1 PHASE A
PHASE B
PHASE C
GROUNDMESSAGE
PROGRAM PORT SETPOINT 789
456
12 3
.0HELP
MESSAGE
VALUE
ACTUAL
ESCAPE
ENTER
RESET
NEXT
DIFFERENTIAL
BLOCKED
745 STATUS SYSTEM STATUS CONDITIONS
SETPOINT GROUP 4
g

These instructions do not purport to cover all details or variations in equipment nor provid
e
for every possible contingency to be met in connection with installation, operation, or main
-
tenance. Should further information be desired or should particular problems arise which ar
e
not covered sufficiently for the purchaser’s purpose, the matter should be referred to th
e
General Electric Company.
To the extent required the products described herein meet applicable ANSI, IEEE, an
d
NEMA standards; but no such assurance is given with respect to local codes and ordi
-
nances because they vary greatly.

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TABLE OF CONTENTS
1. PRODUCT OVERVIEW 1.1 INTRODUCTION
1.1.1 DESCRIPTION .......................................................................................... 1-1
1.1.2 SUMMARY OF PROTECTION FEATURES.............................................. 1-2
1.1.3 ORDER CODES........................................................................................ 1-4
1.2 TECHNICAL SPECIFICATIONS
1.2.1 APPLICABILITY......................................................................................... 1-5
1.2.2 INPUTS...................................................................................................... 1-5
1.2.3 PROTECTION ELEMENTS....................................................................... 1-6
1.2.4 OUTPUTS.................................................................................................. 1-9
2. GETTING STARTED 2.1 USING THE FRONT PANEL DISPLAY
2.1.1 MANEUVERING........................................................................................ 2-1
2.2 CHANGING SETPOINTS
2.2.1 DESCRIPTION .......................................................................................... 2-3
2.2.2 INSTALLING THE SETPOINT ACCESS JUMPER ................................... 2-3
2.2.3 NUMERICAL SETPOINTS ........................................................................ 2-3
2.2.4 ENUMERATION SETPOINTS................................................................... 2-4
2.2.5 TEXT SETPOINTS .................................................................................... 2-5
2.3 SECURITY
2.3.1 INSTALLATION ......................................................................................... 2-6
2.3.2 PASSCODE SECURITY SETUP...............................................................2-6
a CHANGING THE PASSCODE .................................................................. 2-6
b DISABLING/ENABLING PASSCODE SECURITY .................................... 2-7
3. INSTALLATION 3.1 DRAWOUT CASE
3.1.1 CASE DESCRIPTION................................................................................ 3-1
3.1.2 PANEL CUTOUT....................................................................................... 3-1
3.1.3 CASE MOUNTING..................................................................................... 3-2
3.1.4 UNIT WITHDRAWAL AND INSERTION....................................................3-2
a RELAY WITHDRAWAL.............................................................................. 3-2
b RELAY INSERTION................................................................................... 3-3
c DRAWOUT SEAL...................................................................................... 3-3
3.2 TYPICAL WIRING
3.2.1 DESCRIPTION .......................................................................................... 3-4
3.2.2 REAR TERMINAL LAYOUT ...................................................................... 3-4
3.2.3 REAR TERMINAL ASSIGNMENTS........................................................... 3-5
3.2.4 TYPICAL WIRING DIAGRAMS ................................................................. 3-6
3.2.5 PHASE SEQUENCE AND TRANSFORMER POLARITY ......................... 3-8
3.2.6 AC CURRENT TRANSFORMER INPUTS ................................................3-8
3.2.7 AC VOLTAGE INPUT................................................................................ 3-8
3.2.8 CONTROL POWER................................................................................... 3-9
3.2.9 LOGIC INPUTS.......................................................................................... 3-9
3.2.10 ANALOG INPUT...................................................................................... 3-10
3.2.11 TAP POSITION INPUT............................................................................ 3-10
3.2.12 RTD DRIVER/SENSOR........................................................................... 3-10
3.2.13 OUTPUT RELAYS................................................................................... 3-11
3.2.14 SOLID STATE TRIP OUTPUT................................................................. 3-11
3.2.15 ANALOG OUTPUTS................................................................................ 3-11
3.2.16 RS485 / RS422 COMMUNICATION PORTS .......................................... 3-12
3.2.17 RS232 FRONT PANEL PROGRAM PORT ............................................. 3-13
3.2.18 IRIG-B...................................................................................................... 3-14

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3.2.19 DIELECTRIC STRENGTH TESTING ...................................................... 3-14
4. FRONT PANEL
OPERATION 4.1 FRONT PANEL
4.1.1 DESCRIPTION .......................................................................................... 4-1
4.2 DISPLAY, INDICATORS, AND FRONT PORT
4.2.1 DISPLAY.................................................................................................... 4-2
4.2.2 LEDS..........................................................................................................4-2
4.2.3 STATUS INDICATORS.............................................................................. 4-2
a IN SERVICE............................................................................................... 4-2
b SELF-TEST ERROR.................................................................................. 4-2
c TEST MODE.............................................................................................. 4-2
d DIFFERENTIAL BLOCKED ....................................................................... 4-3
e LOCAL....................................................................................................... 4-3
f MESSAGE................................................................................................. 4-3
4.2.4 SYSTEM STATUS INDICATORS..............................................................4-3
a TRANSFORMER DE-ENERGIZED........................................................... 4-3
b TRANSFORMER OVERLOAD .................................................................. 4-3
c LOAD-LIMIT REDUCED............................................................................ 4-3
d SETPOINT GROUP 1................................................................................ 4-3
e SETPOINT GROUP 2................................................................................ 4-3
f SETPOINT GROUP 3................................................................................ 4-3
g
SETPOINT GROUP 4................................................................................ 4-3
4.2.5 CONDITION INDICATORS........................................................................ 4-4
a TRIP........................................................................................................... 4-4
b ALARM....................................................................................................... 4-4
c PICKUP......................................................................................................4-4
d PHASE A (B/C).......................................................................................... 4-4
e GROUND................................................................................................... 4-4
4.2.6 PROGRAM PORT .....................................................................................4-4
4.3 KEYPAD
4.3.1 SETPOINT KEY......................................................................................... 4-5
4.3.2 ACTUAL KEY............................................................................................. 4-5
4.3.3 ESCAPE KEY ............................................................................................ 4-5
4.3.4 ENTER KEY............................................................................................... 4-5
4.3.5 MESSAGE UP/DOWN KEY....................................................................... 4-5
4.3.6 VALUE UP/DOWN KEY............................................................................. 4-5
4.3.7 NUMBER KEYS......................................................................................... 4-6
4.3.8 HELP KEY ................................................................................................. 4-6
4.3.9 RESET KEY............................................................................................... 4-6
4.3.10 NEXT KEY ................................................................................................. 4-6
5. SETPOINTS 5.1 OVERVIEW
5.1.1 SETPOINT GROUPS ................................................................................ 5-1
5.1.2 SETPOINT ENTRY.................................................................................... 5-2
5.1.3 SETPOINT WRITE ACCESS..................................................................... 5-2
5.2 AUTO-CONFIGURATION
5.2.1 DESCRIPTION .......................................................................................... 5-3
5.2.2 A TYPICAL POWER TRANSFORMER ..................................................... 5-3
5.2.3 DYNAMIC CT RATIO MISMATCH CORRECTION ...................................5-3
a PROBLEM 1:USE OF STANDARD CT RATIOS.......................................5-3
b PROBLEM 2: ONLOAD TAP CHANGER ..................................................5-4
5.2.4 PHASE SHIFTS ON THREE-PHASE TRANSFORMERS......................... 5-6
5.2.5 PHASE ANGLE CORRECTION ................................................................5-8
5.2.6 ZERO-SEQUENCE COMPONENT REMOVAL.........................................5-9

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5.2.7 TRANSFORMER TYPES TABLE............................................................ 5-10
5.2.8 TABLE OF PHASE SHIFTS..................................................................... 5-23
5.3 S1 745 SETUP
5.3.1 DESCRIPTION ........................................................................................ 5-24
5.3.2 PASSCODE............................................................................................. 5-24
5.3.3 PREFERENCES...................................................................................... 5-25
5.3.4 COMMUNICATIONS ............................................................................... 5-26
5.3.5 DNP COMMUNICATIONS....................................................................... 5-27
5.3.6 RESETTING ............................................................................................ 5-28
5.3.7 CLOCK..................................................................................................... 5-28
5.3.8 DEFAULT MESSAGES ........................................................................... 5-29
a ADDING DEFAULT MESSAGES ............................................................5-29
b REMOVING DEFAULT MESSAGES....................................................... 5-29
5.3.9 SCRATCHPAD........................................................................................ 5-30
5.3.10 INSTALLATION ....................................................................................... 5-30
5.3.11 745 OPTIONS.......................................................................................... 5-31
5.3.12 UPGRADE OPTIONS.............................................................................. 5-32
5.4 S2 SYSTEM SETUP
5.4.1 DESCRIPTION ........................................................................................ 5-33
5.4.2 TRANSFORMER..................................................................................... 5-33
5.4.3 WINDING 1 (2/3)...................................................................................... 5-35
5.4.4 ONLOAD TAP CHANGER....................................................................... 5-36
5.4.5 HARMONICS........................................................................................... 5-37
5.4.6 FLEXCURVES......................................................................................... 5-37
5.4.7 VOLTAGE INPUT.................................................................................... 5-38
5.4.8 AMBIENT TEMPERATURE..................................................................... 5-39
5.4.9 ANALOG INPUT...................................................................................... 5-40
5.4.10 DEMAND METERING ............................................................................. 5-41
5.4.11 ANALOG OUTPUTS................................................................................ 5-42
5.5 SETPOINTS S3 LOGIC INPUTS
5.5.1 DESCRIPTION ........................................................................................ 5-43
5.5.2 LOGIC INPUTS........................................................................................ 5-43
5.5.3 VIRTUAL INPUTS.................................................................................... 5-44
5.6 S4 ELEMENTS
5.6.1 DESCRIPTION ........................................................................................ 5-45
5.6.2 INTRODUCTION TO ELEMENTS...........................................................5-45
5.6.3 SETPOINT GROUP................................................................................. 5-46
5.6.4 DIFFERENTIAL ....................................................................................... 5-46
a PERCENT DIFFERENTIAL..................................................................... 5-46
b HARMONIC INHIBIT................................................................................ 5-49
c ENERGIZATION INHIBIT........................................................................ 5-49
d ENERGIZATION SENSING..................................................................... 5-50
e 5TH HARMONIC INHIBIT........................................................................ 5-51
5.6.5 INSTANTANEOUS DIFFERENTIAL........................................................ 5-52
5.6.6 PHASE OVERCURRENT........................................................................ 5-52
a WINDING 1 (2/3) PHASE TIME OVERCURRENT..................................5-52
b WINDING 1 (2/3) PHASE INSTANTANEOUS OVERCURRENT 1......... 5-54
c WINDING 1 (2/3) PHASE INSTANTANEOUS OVERCURRENT 2 ........5-54
5.6.7 NEUTRAL OVERCURRENT ................................................................... 5-55
a WINDING 1 (2/3) NEUTRAL TIME OVERCURRENT .............................5-55
b WINDING 1 (2/3) NEUTRAL INSTANTANEOUS OVERCURRENT 1 .... 5-56
c WINDING 1 (2/3) NEUTRAL INSTANTANEOUS OVERCURRENT 2 .... 5-56
5.6.8 GROUND OVERCURRENT .................................................................... 5-57
a WINDING 1 (2/3) GROUND TIME OVERCURRENT .............................. 5-57
b WINDING 1 (2/3) GROUND INSTANTANEOUS OVERCURRENT 1.....5-58
c WINDING 1 (2/3) GROUND INSTANTANEOUS OVERCURRENT 2.....5-58
5.6.9 RESTRICTED GROUND (DIFFERENTIAL GROUND)........................... 5-59
a WINDING 1 (2/3) RESTRICTED GROUND FAULT................................ 5-59

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b RESTRICTED GROUND FAULT SETTINGS EXAMPLE........................ 5-61
c SETPOINTS............................................................................................. 5-62
5.6.10 NEGATIVE SEQUENCE OVERCURRENT.............................................5-63
a WINDING 1 (2/3) NEGATIVE SEQUENCE TIME OVERCURRENT.......5-63
b WINDING 1 (2/3) NEG. SEQ. INSTANTANEOUS OVERCURRENT...... 5-64
5.6.11 FREQUENCY .......................................................................................... 5-65
a UNDERFREQUENCY 1 (2) ..................................................................... 5-65
b FREQUENCY DECAY............................................................................. 5-66
c OVERFREQUENCY ................................................................................ 5-67
5.6.12 OVEREXCITATION .................................................................................5-68
a 5TH HARMONIC LEVEL ......................................................................... 5-68
b VOLTS-PER-HERTZ 1 (2)....................................................................... 5-69
5.6.13 HARMONICS........................................................................................... 5-70
a WINDING 1 (2/3) THD LEVEL................................................................. 5-70
b WINDING 1 (2/3) HARMONIC DERATING ............................................. 5-71
5.6.14 INSULATION AGING / LOSS OF LIFE FEATURE.................................. 5-72
a DESCRIPTION ........................................................................................ 5-72
b HOTTEST-SPOT LIMIT........................................................................... 5-72
c INSULATION AGING SETPOINTS ......................................................... 5-73
5.6.15 AGING FACTOR LIMIT ........................................................................... 5-74
5.6.16 LOSS OF LIFE LIMIT...............................................................................5-75
5.6.17 ANALOG INPUT ...................................................................................... 5-76
a ANALOG LEVEL 1 (2) ............................................................................. 5-76
5.6.18 CURRENT DEMAND...............................................................................5-77
5.6.19 TRANSFORMER OVERLOAD ................................................................ 5-78
5.6.20 TAP CHANGER FAILURE....................................................................... 5-79
5.7 S5 OUTPUTS
5.7.1 DESCRIPTION ........................................................................................ 5-80
5.7.2 INTRODUCTION TO FLEXLOGIC™.......................................................5-80
5.7.3 FLEXLOGIC™ RULES ............................................................................ 5-82
5.7.4 OUTPUT RELAYS...................................................................................5-84
5.7.5 TRACE MEMORY.................................................................................... 5-85
5.7.6 VIRTUAL OUTPUTS................................................................................ 5-85
5.7.7 TIMERS ................................................................................................... 5-86
5.8 S6 TESTING
5.8.1 DESCRIPTION ........................................................................................ 5-87
5.8.2 OUTPUT RELAYS...................................................................................5-87
5.8.3 ANALOG OUTPUTS................................................................................ 5-87
5.8.4 SIMULATION........................................................................................... 5-88
5.8.5 PREFAULT VALUES...............................................................................5-89
5.8.6 FAULT VALUES ...................................................................................... 5-90
5.8.7 FACTORY SERVICE...............................................................................5-90
5.9 TIME OVERCURRENT CURVES
5.9.1 NOTE....................................................................................................... 5-91
5.9.2 ANSI CURVES......................................................................................... 5-91
5.9.3 DEFINITE TIME CURVE .........................................................................5-93
5.9.4 IEC CURVES........................................................................................... 5-93
5.9.5 IAC CURVES........................................................................................... 5-95
5.10 INVERSE VOLTS-PER-HERTZ CURVES
5.10.1 INVERSE CURVE 1.................................................................................5-97
5.10.2 INVERSE CURVE 2.................................................................................5-98
5.10.3 INVERSE CURVE 3.................................................................................5-99
6. ACTUAL VALUES 6.1 OVERVIEW
6.1.1 DESCRIPTION .......................................................................................... 6-1

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TABLE OF CONTENTS
6.1.2 ACTUAL VALUES ORGANIZATION......................................................... 6-1
6.2 A1 STATUS
6.2.1 DESCRIPTION .......................................................................................... 6-2
6.2.2 DATE AND TIME ....................................................................................... 6-2
6.2.3 LOGIC INPUTS.......................................................................................... 6-2
6.2.4 VIRTUAL INPUTS...................................................................................... 6-2
6.2.5 OUTPUT RELAYS..................................................................................... 6-3
6.2.6 VIRTUAL OUTPUTS.................................................................................. 6-3
6.2.7 SELF-TEST ERRORS............................................................................... 6-3
6.3 A2 METERING
6.3.1 DESCRIPTION .......................................................................................... 6-4
6.3.2 CURRENT ................................................................................................. 6-4
a WINDING 1/2/3 CURRENTS..................................................................... 6-4
b POSITIVE SEQUENCE CURRENTS........................................................ 6-5
c NEGATIVE SEQUENCE CURRENTS....................................................... 6-5
d ZERO SEQUENCE CURRENTS............................................................... 6-5
e DIFFERENTIAL CURRENT....................................................................... 6-6
f RESTRAINT CURRENT............................................................................ 6-6
g
GROUND DIFFERENTIAL CURRENT...................................................... 6-6
6.3.3 HARMONIC CONTENT............................................................................. 6-7
a HARMONIC SUB-COMPONENTS............................................................ 6-7
b TOTAL HARMONIC DISTORTION (THD)................................................. 6-7
c HARMONIC DERATING FACTOR............................................................ 6-8
6.3.4 FREQUENCY ............................................................................................ 6-8
6.3.5 TAP CHANGER......................................................................................... 6-8
6.3.6 VOLTAGE.................................................................................................. 6-9
6.3.7 DEMAND ................................................................................................... 6-9
a DEMAND DATA CLEAR............................................................................ 6-9
b CURRENT DEMAND............................................................................... 6-10
6.3.8 AMBIENT TEMPERATURE..................................................................... 6-10
6.3.9 LOSS OF LIFE......................................................................................... 6-10
6.3.10 ANALOG INPUT...................................................................................... 6-11
6.3.11 POWER ................................................................................................... 6-11
6.3.12 ENERGY.................................................................................................. 6-12
a ENERGY DATA CLEAR..........................................................................6-12
b W1/W2/W3 ENERGY............................................................................... 6-12
6.4 A3 EVENT RECORDER
6.4.1 DESCRIPTION ........................................................................................ 6-13
6.4.2 EVENT DATA RESET ............................................................................. 6-13
6.4.3 EVENT RECORDS.................................................................................. 6-13
6.5 A4 PRODUCT INFO
6.5.1 DESCRIPTION ........................................................................................ 6-17
6.5.2 TECHNICAL SUPPORT.......................................................................... 6-17
6.5.3 REVISION CODES.................................................................................. 6-17
6.5.4 CALIBRATION......................................................................................... 6-18
6.6 TARGET MESSAGES
6.6.1 DESCRIPTION ........................................................................................ 6-19
6.7 SELF-TEST ERRORS
6.7.1 DESCRIPTION ........................................................................................ 6-21
6.7.2 MAJOR SELF-TEST ERRORS................................................................ 6-21
6.7.3 MINOR SELF-TEST ERRORS ................................................................ 6-21
6.8 FLASH MESSAGES
6.8.1 DESCRIPTION ........................................................................................ 6-23

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7. SCHEME LOGIC 7.1 INTRODUCTION
7.1.1 DESCRIPTION .......................................................................................... 7-1
7.1.2 SETPOINTS............................................................................................... 7-1
7.1.3 MEASUREMENT UNITS ........................................................................... 7-1
7.1.4 TIME DELAYS ........................................................................................... 7-1
7.1.5 LED INDICATORS.....................................................................................7-1
7.1.6 LOGIC........................................................................................................7-1
7.2 BLOCK DIAGRAMS
7.2.1 DIFFERENTIAL SCHEME LOGIC............................................................. 7-2
7.2.2 OVERCURRENT SCHEME LOGIC........................................................... 7-8
7.2.3 FREQUENCY LOGIC .............................................................................. 7-20
8. COMMUNICATIONS 8.1 OVERVIEW
8.1.1 PROTOCOLS ............................................................................................ 8-1
8.1.2 PHYSICAL LAYER .................................................................................... 8-1
8.2 MODBUS PROTOCOL
8.2.1 DESCRIPTION .......................................................................................... 8-2
8.2.2 GE POWER MANAGEMENT MODBUS PROTOCOL .............................. 8-2
8.2.3 ELECTRICAL INTERFACE ....................................................................... 8-2
8.2.4 DATA FRAME FORMAT AND RATE ........................................................ 8-2
8.2.5 DATA PACKET FORMAT.......................................................................... 8-3
8.2.6 CRC-16 ALGORITHM................................................................................ 8-4
8.2.7 MESSAGE TIMING.................................................................................... 8-4
8.2.8 SUPPORTED FUNCTION CODES ........................................................... 8-5
8.2.9 FUNCTION CODE 03H/04H: READ ACTUAL VALUES/SETPOINTS ...... 8-6
8.2.10 FUNCTION CODE 05H: EXECUTE OPERATION ....................................8-7
8.2.11 FUNCTION CODE 06H: STORE SINGLE SETPOINT..............................8-8
8.2.12 FUNCTION CODE 10H: STORE MULTIPLE SETPOINTS.......................8-9
8.2.13 EXCEPTION RESPONSES..................................................................... 8-10
8.2.14 READING THE EVENT RECORDER...................................................... 8-11
8.2.15 READING TRACE MEMORY .................................................................. 8-11
8.2.16 ACCESSING DATA VIA THE USER MAP ..............................................8-12
8.2.17 FUNCTION CODE SUBSTITUTIONS ..................................................... 8-15
a FUNCTION CODE 03H AND 04 SUBSTITUTIONS................................8-15
b FUNCTION CODE 05H SUBSTITUTION................................................ 8-15
c FUNCTION CODE 06H SUBSTITUTION................................................ 8-16
8.2.18 MEMORY MAP ORGANIZATION............................................................8-16
8.3 MODBUS MEMORY MAP
8.3.1 745 MEMORY MAP.................................................................................8-17
8.3.2 MEMORY MAP DATA FORMATS...........................................................8-74
8.4 DNP COMMUNICATIONS
8.4.1 DEVICE PROFILE DOCUMENT .............................................................8-92
8.4.2 IMPLEMENATION TABLE....................................................................... 8-94
8.5 POINT LISTS
8.5.1 POINT LIST TABLES...............................................................................8-96
9. 745 PC SOFTWARE 9.1 OVERVIEW
9.1.1 DESCRIPTION .......................................................................................... 9-1
9.1.2 HARDWARE & SOFTWARE REQUIREMENTS .......................................9-2
9.1.3 MENU SUMMARY.....................................................................................9-2

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9.1.4 TOOLBAR.................................................................................................. 9-3
9.1.5 HARDWARE CONFIGURATION............................................................... 9-3
9.2 INSTALLATION & CONFIGURATION
9.2.1 745PC INSTALLATION ............................................................................. 9-5
9.2.2 STARTUP & COMMUNICATIONS CONFIGURATION.............................9-6
9.3 USING 745PC
9.3.1 SAVING SETPOINTS TO A FILE.............................................................. 9-7
9.3.2 745 FIRMWARE UPGRADES ................................................................... 9-8
9.3.3 LOADING SETPOINTS FROM A FILE...................................................... 9-9
9.3.4 ENTERING SETPOINTS........................................................................... 9-9
9.3.5 VIEWING ACTUAL VALUES................................................................... 9-11
10. COMMISSIONING 10.1 GENERAL
10.1.1 INTRODUCTION ..................................................................................... 10-1
10.1.2 TESTING PHILOSOPHY......................................................................... 10-1
10.1.3 SAFETY PRECAUTIONS........................................................................ 10-2
10.1.4 CONVENTIONS....................................................................................... 10-2
10.2 TEST EQUIPMENT
10.2.1 TEST SETUP........................................................................................... 10-3
10.3 GENERAL PRELIMINARY WORK
10.3.1 DESCRIPTION ........................................................................................ 10-4
10.3.2 DIELECTRIC STRENGTH TESTING......................................................10-5
10.4 LOGIC INPUTS & OUTPUT RELAYS
10.4.1 LOGIC INPUTS........................................................................................ 10-6
a PROCEDURE.......................................................................................... 10-6
10.4.2 OUTPUT RELAYS................................................................................... 10-7
a PROCUDURE:......................................................................................... 10-7
10.5 DISPLAY, METERING, COMMUNICATIONS, ANALOG
OUTPUTS
10.5.1 DESCRIPTION ........................................................................................ 10-8
10.5.2 CURRENT INPUTS ................................................................................. 10-8
10.5.3 VOLTAGE INPUT.................................................................................... 10-9
10.5.4 TRANSFORMER-TYPE SELECTION..................................................... 10-9
a AUTOMATIC TRANSFORMATION PERFORMED IN THE 745............. 10-9
b EFFECTS OF ZERO-SEQUENCE COMPONENT REMOVAL ............. 10-10
10.5.5 AMBIENT TEMPERATURE INPUT....................................................... 10-11
a BASIC CALIBRATION OF RTD INPUT................................................. 10-11
b DETAILED CALIBRATION OF RTD INPUT .......................................... 10-11
c AMBIENT TEMPERATURE BY MONTHLY AVERAGES......................10-12
10.5.6 ANALOG OUTPUTS.............................................................................. 10-13
10.5.7 TAP POSITION...................................................................................... 10-13
10.6 PROTECTION SCHEMES
10.6.1 WARNING.............................................................................................. 10-14
10.6.2 HARMONIC RESTRAINED PERCENT DIFFERENTIAL ...................... 10-14
a MINIMUM PICKUP ................................................................................ 10-14
b VERIFICATION OF LOCAL RESET MODE.......................................... 10-15
c VERIFICATION OF REMOTE RESET MODE....................................... 10-15
d VERIFICATION OF SOLID STATE OUTPUT........................................ 10-15
e BASIC OPERATING TIME .................................................................... 10-16
f SLOPE MEASUREMENTS.................................................................... 10-16
g
SLOPE KNEEPOINT............................................................................. 10-17
h 2nd HARMONIC RESTRAINT............................................................... 10-18
i 5th HARMONIC RESTRAINT................................................................ 10-18
j ENERGIZATION DETECTION SCHEME.............................................. 10-19

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k TARGET, OUTPUT CONTACT, & DISPLAY OPERATION ..................10-20
l BLOCKING FROM LOGIC INPUTS ...................................................... 10-20
10.6.3 INSTANTANEOUS DIFFERENTIAL PROTECTION ............................. 10-20
a MINIMUM PICKUP ................................................................................ 10-20
b OPERATING TIME ................................................................................ 10-20
c TARGET, OUTPUT CONTACT, & DISPLAY OPERATION ..................10-21
d BLOCKING FROM LOGIC INPUTS ...................................................... 10-21
10.6.4 PHASE TIME OVERCURRENT ............................................................10-21
a WINDING #1 ELEMENTS...................................................................... 10-21
b PICKUP LEVEL ..................................................................................... 10-22
c OPERATING TIME ................................................................................ 10-22
d RESET TIME ......................................................................................... 10-22
e PHASE B AND C ELEMENTS...............................................................10-22
f WINDING #2 AND #3 ELEMENTS........................................................10-23
10.6.5 PHASE INSTANTANEOUS OVERCURRENT 1 ...................................10-23
a WINDING #1 ELEMENTS...................................................................... 10-23
b PICKUP LEVEL ..................................................................................... 10-23
c OPERATING TIME ................................................................................ 10-23
d PHASE B AND C ELEMENTS...............................................................10-23
e WINDING #2 AND #3 ELEMENTS........................................................10-24
10.6.6 PHASE INSTANTANEOUS OVERCURRENT 2 ...................................10-24
10.6.7 NEUTRAL TIME OVERCURRENT........................................................10-24
a WINDING #1 ELEMENT........................................................................ 10-24
b PICKUP LEVEL ..................................................................................... 10-24
c OPERATING TIME ................................................................................ 10-25
d RESET TIME ......................................................................................... 10-25
e WINDING #2 OR WINDING #3 ELEMENTS.........................................10-25
10.6.8 NEUTRAL INSTANTANEOUS OVERCURRENT 1............................... 10-26
a WINDING #1 ELEMENT........................................................................ 10-26
b PICKUP LEVEL ..................................................................................... 10-26
c OPERATING TIME ................................................................................ 10-26
d WINDING 2 AND 3 ELEMENTS............................................................10-26
10.6.9 NEUTRAL INSTANTANEOUS OVERCURRENT 2............................... 10-27
10.6.10 GROUND TIME OVERCURRENT......................................................... 10-27
a WINDING 1 ELEMENT.......................................................................... 10-27
b PICKUP LEVEL ..................................................................................... 10-27
c OPERATING TIME ................................................................................ 10-28
d RESET TIME ......................................................................................... 10-28
e WINDING 2 OR 3 ELEMENTS .............................................................. 10-28
10.6.11 GROUND INSTANTANEOUS OVERCURRENT 1................................ 10-28
a WINDING 1 ELEMENT.......................................................................... 10-28
b PICKUP LEVEL ..................................................................................... 10-29
c OPERATING TIME ................................................................................ 10-29
d WINDING 2 OR ELEMENT.................................................................... 10-29
10.6.12 GROUND INSTANTANEOUS OVERCURRENT 2................................ 10-29
10.6.13 RESTRICTED GROUND FAULT........................................................... 10-30
a WINDING #1 ELEMENT........................................................................ 10-30
b PICKUP LEVEL ..................................................................................... 10-30
c OPERATING TIME ................................................................................ 10-31
d SLOPE................................................................................................... 10-31
e WINDING 2 OR 3 ELEMENTS .............................................................. 10-31
10.6.14 NEGATIVE SEQUENCE TIME OVERCURRENT ................................. 10-31
a WINDING #1 ELEMENT........................................................................ 10-31
b PICKUP LEVEL ..................................................................................... 10-32
c OPERATING TIME ................................................................................ 10-32
d RESET TIME ......................................................................................... 10-33
e WINDINGS 2 AND 3 ELEMENTS..........................................................10-33
10.6.15 NEGATIVE SEQUENCE INSTANTANEOUS OVERCURRENT ...........10-33
a WINDING 1 ELEMENT.......................................................................... 10-33
b PICKUP LEVEL ..................................................................................... 10-33
c OPERATING TIME ................................................................................ 10-34
d WINDING 2 AND 3 ELEMENTS............................................................10-34
10.6.16 FREQUENCY ELEMENTS.................................................................... 10-34

GE Power Management 745 Transformer Management Relay
ix
TABLE OF CONTENTS
10.6.17 UNDERFREQUENCY 1......................................................................... 10-35
a PRELIMINARIES ................................................................................... 10-35
b VOLTAGE INPUT FUNCTION (VOLTAGE INPUT ENABLED)............. 10-35
c CURRENT INPUT FUNCTION (VOLTAGE INPUT DISABLED)........... 10-36
10.6.18 UNDERFREQUENCY 2......................................................................... 10-37
10.6.19 OVERFREQUENCY .............................................................................. 10-37
a PRELIMINARIES ................................................................................... 10-37
b VOLTAGE INPUT FUNCTION (VOLTAGE INPUT ENABLED)............. 10-37
c CURRENT INPUT FUNCTION (VOLTAGE INPUT DISABLED)........... 10-38
10.6.20 FREQUENCY DECAY RATE 1 ............................................................. 10-39
a PRELIMINARIES ................................................................................... 10-39
b VOLTAGE INPUT FUNCTION (VOLTAGE INPUT ENABLED)............. 10-39
c CURRENT INPUT FUNCTION (VOLTAGE INPUT DISABLED)........... 10-40
d FREQUENCY DECAY RATE 2, 3, & 4.................................................. 10-40
10.6.21 VOLTS-PER-HZ 1(2)............................................................................. 10-41
10.6.22 5TH HARMONIC SCHEME................................................................... 10-41
10.6.23 INSULATION AGING............................................................................. 10-42
a PRELIMINARIES ................................................................................... 10-42
b HOTTEST SPOT LIMIT......................................................................... 10-42
c AGING FACTOR LIMIT ......................................................................... 10-42
d LOSS-OF-LIFE LIMIT............................................................................ 10-42
10.6.24 TAP MONITOR FAILURE...................................................................... 10-42
10.7 AUXILIARY PROTECTION/MONITORING FUNCTIONS
10.7.1 THD LEVEL SCHEME........................................................................... 10-43
a MINIMUM PICKUP ................................................................................ 10-43
b OPERATING TIME................................................................................ 10-43
c MINIMUM OPERATING CURRENT...................................................... 10-43
d OTHER THD ELEMENTS...................................................................... 10-43
10.7.2 HARMONIC DERATING FUNCTION.................................................... 10-44
a OPERATING LEVEL.............................................................................. 10-44
b OPERATING TIME................................................................................ 10-44
10.7.3 TRANSFORMER OVERLOAD .............................................................. 10-45
a OPERATING LEVEL.............................................................................. 10-45
b OPERATING TIME................................................................................ 10-45
10.8 PLACING RELAY INTO SERVICE
10.8.1 DESCRIPTION ...................................................................................... 10-46
11. SETPOINT TABLES 11.1 COMMISSIONING SUMMARY
11.1.1 S1 745 SETUP......................................................................................... 11-1
11.1.2 S2 SYSTEM SETUP................................................................................ 11-2
11.1.3 FLEXCURVES......................................................................................... 11-4
11.1.4 S3 LOGIC INPUTS.................................................................................. 11-5
11.1.5 S4 ELEMENTS........................................................................................ 11-6
11.1.6 S5 OUTPUTS ........................................................................................ 11-18
A. FIGURES AND TABLES A.1 FIGURES AND TABLES
A.1.1 LIST OF FIGURES....................................................................................A-1
A.1.2 LIST OF TABLES.......................................................................................A-2
B. EU DECLARATION OF
CONFORMITY B.1 EU DECLARATION OF CONFORMITY

x
745 Transformer Management Relay GE Power Management
TABLE OF CONTENTS
C. WARRANTY C.1 WARRANTY INFORMATION
C.1.1 WARRANTY ..............................................................................................C-1

GE Power Management 745 Transformer Management Relay 1-1
1 PRODUCT OVERVIEW 1.1 INTRODUCTION
1
1 PRODUCT OVERVIEW 1.1 INTRODUCTION 1.1.1 DESCRIPTION
The 745 is a high speed, multi-processor based, 3-phase, two or three winding, Transformer Management
Relay™ intended for the primary protection and management of small, medium and large power transformers.
The 745 combines Percent Differential, Overcurrent, Frequency and Overexcitation protection elements along
with monitoring of individual harmonics, and THD in one economical package.
The relay provides a variety of adaptive relaying features:
• Adaptive Harmonic Restraint which addresses the problem of false tripping during inrush
• Adaptive Time Overcurrent Elements which will adjust their pickup settings based on the calculated trans-
former capability when supplying load currents with high harmonic content
• Multiple Setpoint Groups which allow the user to enter and dynamically select from up to four groups of
relay settings to address the protection requirements of different power system configurations
• Dynamic CT Ratio Mismatch Correction which monitors the on-load tap position and automatically corrects
for CT ratio mismatch
• FlexLogic™ which allows PLC style equations based on logic inputs & protection elements to be assigned
to any of the 745 outputs.
The 745 also includes a powerful testing and simulation feature. This allows the protection engineer the ability
to test the relay operation based on captured or computer generated waveform data which can be converted to
a digitized format and downloaded into the 745’s simulation buffer for “playback”.
The 745 also provides its own Waveform Capture function which will record waveform data for fault, inrush or
alarm conditions.
The Auto-Configuration function eliminates the need for any special CT connections by having all CTs con-
nected in wye.

1-2 745 Transformer Management Relay GE Power Management
1.1 INTRODUCTION 1 PRODUCT OVERVIEW
11.1.2 SUMMARY OF PROTECTION FEATURES
SYMBOL COMMON PROTECTION ELEMENT SYMBOL WINDING 2 PROTECTION ELEMENT
59/81-1 Volts-Per-Hertz 1 250/46 Negative Sequence Instantaneous O/C
59/81-2 Volts-Per-Hertz 2 251/46 Negative Sequence Time O/C
81U-1 Underfrequency 1 250P1 Phase Instantaneous O/C 1
81U-2 Underfrequency 2 250P2 Phase Instantaneous O/C 2
81U-R1 Frequency Decay Rate 1 250N1 Neutral (3I0) Instantaneous O/C 1
81U-R2 Frequency Decay Rate 2 250N2 Neutral (3I0) Instantaneous O/C 2
81U-R3 Frequency Decay Rate 3 250G1 Ground Instantaneous O/C 1
81U-R4 Frequency Decay Rate 4 250G2 Ground Instantaneous O/C 2
81-H5 5th Harmonic Level 251P Phase Time O/C
81O Overfrequency 251N Neutral (3I0) Time O/C
87 Differential (Percent) 251G Ground Time O/C
50/87 Instantaneous Differential 287TG Ground Differential (Restricted Ground Fault)
AN-1 Analog Input Level 1 2THD Total Harmonic Distortion Level
AN-2 Analog Input Level 2 2AD Current Demand
Insulation Aging
– Aging Factor
– Hottest Spot Limit
– Total Accumulated Life
Tap Changer Monitor
SYMBOL WINDING 1 PROTECTION ELEMENT SYMBOL WINDING 3 PROTECTION ELEMENT
150/46 Negative Sequence Instantaneous O/C 350/46 Negative Sequence Instantaneous O/C
151/46 Negative Sequence Time O/c 351/46 Negative Sequence Time O/c
150P1 Phase Instantaneous O/C 1 350P1 Phase Instantaneous O/C 1
150P2 Phase Instantaneous O/C 2 350P2 Phase Instantaneous O/C 2
150N1 Neutral (3I0) Instantaneous O/C 1 350N1 Neutral (3I0) Instantaneous O/C 1
150N2 Neutral (3I0) Instantaneous O/C 2 350N2 Neutral (3I0) Instantaneous O/C 2
150G1 Ground Instantaneous O/C 1 351P Phase Time O/C
150G2 Ground Instantaneous O/C 2 351N Neutral (3I0) Time O/C
151P Phase Time O/C 351G Ground Time O/C
151N Neutral (3I0) Time O/C 387TG Ground Differential (Restricted Ground Fault)
151G Ground Time O/C 3THD Total Harmonic Distortion Level
187TG Ground Differential (Restricted Ground Fault) 3AD Current Demand
1THD Total Harmonic Distortion Level
1AD Current Demand

GE Power Management 745 Transformer Management Relay 1-3
1 PRODUCT OVERVIEW 1.1 INTRODUCTION
1
Figure 1–1: SINGLE LINE DIAGRAM
745

1-4 745 Transformer Management Relay GE Power Management
1.1 INTRODUCTION 1 PRODUCT OVERVIEW
11.1.3 ORDER CODES
Figure 1–2: 745 ORDER CODES
745
TRANSFORMER
MANAGEMENT
RELAY
®
WINDINGS PER PHASE
PHASE CURRENT INPUT RATINGS
GROUND CURRENT INPUT RATINGS
W2=2WINDING
W3=3WINDING
WINDING
WINDING
1
1/2
2
2/3
3
P1
P5
P15
P51
P115
P151
P155
P511
P515
P551
G1
G5
G15
G51
=
=
=
=
=
=
=
=
=
=
=
=
=
=
1A
5A
1A
5A
1A
1A
1A
5A
5A
5A
1A
5A
1A
5A
1A
5A
5A
1A
1A
5A
5A
1A
1A
5A
1A
5A
5A
1A
(1 A)
(5 A)
—
—
5A
1A
5A
1A
5A
1A
OPTIONS
A = ANALOG INPUT/OUTPUTS
L = LOSS OF LIFE
R = RESTRICTED GROUND FAULT
CONTROL POWER
LO = 24-60 Vdc
20-48 Vac @ 48-62 Hz
HI = 90-300 Vdc
70-265 Vac @ 48-62 Hz
745ORDER.CDR
745 W2 P5 G5 LO AR
L

GE Power Management 745 Transformer Management Relay 1-5
1 PRODUCT OVERVIEW 1.2 TECHNICAL SPECIFICATIONS
1
1.2 TECHNICAL SPECIFICATIONS 1.2.1 APPLICABILITY
Transformers: 2 Winding or 3 Winding
Frequency: 50 or 60 Hz nominal
(frequency tracking allows operation from 2 to 65 Hz)
1.2.2 INPUTS
CONTROL POWER (POWER SUPPLY)
Options: LO/HI (specified when ordering)
LO Range: DC = 20 to 60 V; AC = 20 to 48 V @ 48 to 62 Hz
HI Range: DC = 90 to 300 V; AC = 70 to 265 V @ 48 to 62 Hz
Power: 30 VA nominal, 40 VA maximum
Fuse (not accessible): Hi-Volt: Current rating: 3.15 A
Type: 5 × 20 mm Slow-Blow Littelfuse, High Breaking Capacity
Model #: 2153.15
Low-Volt: Current rating: 3.15 A
Type: 5 × 20 mm Slow-Blow Littelfuse, High Breaking Capacity
Model #: 2153.15
PHASE CURRENT INPUT
Source CT: 1 to 50000 A primary / 1 or 5 A secondary
Relay Input: 1 A or 5 A (specified when ordering)
Burden: Less than 0.2 VA at rated load per phase
Conversion Range: 0.02 to 46 ×CT
Accuracy: at <4 x CT: ± 0.25% of 4 ×CT (± 0.01 ×CT)
at ≥4 x CT: ± 0.5% of 46 ×CT (± 0.2 ×CT)
Overload Withstand: 1 second at 80 times rated current
2 seconds at 40 times rated current
continuous at 3 times rated current
GROUND CURRENT INPUT
Source CT: 1 to 50000 A primary / 1 or 5 A secondary
Relay Input: 1 A or 5 A (specified when ordering)
Burden: Less than 0.2 VA at rated load
Conversion Range: 0.02 to 46 ×CT
Accuracy: at <4 ×CT: ± 0.25% of 4 x CT (± 0.01 ×CT)
at ≥4 ×CT: ± 0.5% of 46 x CT (± 0.2 ×CT)
Overload Withstand: 1 second at 80 times rated current
2 seconds at 40 times rated current
continuous at 3 times rated current
VOLTAGE INPUTS
Source VT: 2 to 600 kV / 60 to 120 V
Source VT Ratio: 1 to 5000 in steps of 1
Relay Input: 60 V to 120 V phase-neutral
Burden: Less than 0.025 VA at 120 V
Max. Continuous: 273 V
Accuracy: ± 1% of 2 ×VT (± 0.02 ×VT)
LOGIC INPUTS (16)
Dry Contacts: 1000 Ωmaximum ON resistance (32 V DC at 2 mA provided by 745)
Wet Contacts: Inputs 1 to 16: 30 to 300 V DC at 1.5 mA

1-6 745 Transformer Management Relay GE Power Management
1.2 TECHNICAL SPECIFICATIONS 1 PRODUCT OVERVIEW
1ANALOG INPUT
Type: DC mA
Ranges: 0-1 mA, 0-5 mA, 0-10 mA, 0-20 mA, or 4-20 mA (programmable)
Input Impedance: 375 Ω± 10%
Conversion Range: 0 to 21 mA
Accuracy: ± 1% of full scale (based on input range)
TAP POSITION
Type: resistance (ohms)
Range: 0 to 500 Ωor 0.5 to 5.0 kΩ
Bias Current: 1 mA or 10 mA (based on input range)
Accuracy: ± 1% of full scale (based on input range)
RTD
Type: 3 wire
RTD Type 100 ΩPlatinum (DIN.43760)
100 ΩNickel
120 ΩNickel
IRIG-B INPUT
Amplitude-Modulated: 1.0 to 10 V pk-pk
DC Shift: TTL
Input Impedance 70 to 100 kΩ
1.2.3 PROTECTION ELEMENTS
PERCENT DIFFERENTIAL PROTECTION
Operating Current Pickup: 0.05 to 1.00 in steps of 0.01 x CT
Dropout Level: 97 to 98% of Pickup
SLOPE-1 Range: 15% to 100% in steps of 1
SLOPE-2 Range: 50% to 200% in steps of 1
KP (SLOPE-1 Kneepoint): 1.0 to 20.0 in steps of 0.1 x CT
Harmonic Restraint: 0.1% to 65.0% in steps of 0.1
Operate Time: Solid State Output: Pickup < 1 x CT: 42 to 52 ms
1 x CT < Pickup < 1.1 ×kneepoint: 34 to 44 ms
Pickup > 1.1 ×kneepoint: 26 to 36 ms
Relay Outputs 2-5: Pickup < 1 x CT: 46 to 56 ms
1 x CT < Pickup < 1.1 ×kneepoint: 38 to 48 ms
Pickup > 1.1 ×kneepoint: 30 to 40 ms
INSTANTANEOUS DIFFERENTIAL OVERCURRENT
Pickup Level: 3.00 to 20.00 in steps of 0.01 x CT
Dropout Level: 97 to 98% of Pickup
Level Accuracy: Per current input
Operate Time: Solid State Output: at 1.2 x pickup: 22 to 30 ms
at 2.0 x pickup: 18 to 26 ms
at 4.0 x pickup:11 to 19 ms
Relay Outputs 2-5: at 1.2 x pickup: 28 to 36 ms
at 2.0 x pickup: 24 to 32 ms
at 4.0 x pickup: 17 to 25 ms

GE Power Management 745 Transformer Management Relay 1-7
1 PRODUCT OVERVIEW 1.2 TECHNICAL SPECIFICATIONS
1
PHASE / NEUTRAL / GROUND / NEGATIVE SEQUENCE TIME OVERCURRENT
Pickup Level: 0.05 to 20.00 in steps of 0.01 x CT
Dropout Level: 97 to 98% of Pickup
Curve Shape: ANSI Extremely/Very/Moderately/Normally Inverse;
Definite Time (0.1 s base curve);
IEC Curve A/B/C and Short;
FlexCurve™ A/B/C (programmable curves);
IAC Extreme/Very/Inverse/Short
Curve Multiplier Time Dial: 0.5 to 30 for ANSI, IAC & FlexCurves™ in steps of 0.1 s;
0.05 to 100.00 for IEC curves in steps of 0.01
Reset Type: Instantaneous or Linear
Level Accuracy: Per current input
Timing Accuracy: at ≥1.03 ×pickup: ± 3% of trip time or ± 20 ms (whichever is greater)
PHASE / NEUTRAL / GROUND / NEGATIVE SEQUENCE INSTANTANEOUS OVERCURRENT
Pickup Level: 0.05 to 20.00 in steps of 0.01 ×CT
Dropout Level: 97 to 98% of Pickup
Time Delay: 0 to 60000 in steps of 1 ms
Level Accuracy: Per current input
Operate Time: Solid State Output: at 1.2 ×pickup: 22 to 30 ms
at 2.0 ×pickup: 18 to 26 ms
at 4.0 ×pickup: 11 to 19 ms
Relay Outputs 2-5: at 1.2 ×pickup: 28 to 36 ms
at 2.0 ×pickup: 24 to 32 ms
at 4.0 ×pickup: 17 to 25 ms
UNDERFREQUENCY (2 ELEMENTS)
Operating Current Pickup: 0.05 to 1.00 in steps of 0.01 ×CT
Operating Voltage Pickup 0.10 to 0.99 in steps of 0.01 ×VT
Pickup Level: 45.00 to 59.99 in steps of 0.01 Hz
Dropout Level: Pickup + 0.03 Hz
Time Delay: 0.00 to 600.00 s in steps of 0.01 s
Signal Source: Winding 1 phase A current / voltage
Level Accuracy: ±0.02 Hz
Operate Time: Solid State Output: at 3% beyond pickup: 120 to 150 ms
Relay Outputs 2 to 5: at 3% beyond pickup: 125 to 155 ms (delay set at 0.0 sec.)
FREQUENCY RATE OF CHANGE (4 ELEMENTS)
Operating Current Pickup: 0.05 to 1.00 in steps of 0.01 ×CT
Operating Voltage Pickup 0.10 to 0.99 in steps of 0.01 ×VT
Pickup Level: 45.00 to 59.99 in steps of 0.01 Hz
Dropout Level: Pickup + 0.03 Hz
Rate 1/2/3/4: 0.1 to 5.0 in steps of 0.1 Hz/sec.
Dropout Level: Pickup + 0.07 Hz/sec.
Signal Source: 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 supervision frequency level.

1-8 745 Transformer Management Relay GE Power Management
1.2 TECHNICAL SPECIFICATIONS 1 PRODUCT OVERVIEW
1OVERFREQUENCY (1 ELEMENT)
Operating Current Pickup: 0.05 to 1.00 in steps of 0.01 ×CT
Operating Voltage Pickup 0.10 to 0.99 in steps of 0.01 ×VT
Pickup Level: 50.01 to 65.00 in steps of 0.01 Hz
Dropout Level: Pickup – 0.03 Hz
Time Delay: 0.00 to 600.00 s in steps of 0.01 s
Signal Source: Winding 1 phase A current / voltage
Level Accuracy: ±0.02 Hz
Operate Time: Solid State Output: at 3% beyond pickup: 120 to 150 ms
Relay Outputs 2-5: at 3% beyond pickup: 125 to 155 ms (delay set to 0.0 s)
OVEREXCITATION ON VOLTS/HERTZ (2 ELEMENTS)
Operating Voltage Pickup: 0.10 to 0.99 in steps of 0.01 ×VT
Pickup Level: 1.00 to 4.00 in steps of 0.01 V/Hz
Curve Shape: Definite Time (0.1 sec. base curve);
IEC Curve A/B/C
Time Delay: 0.00 to 600.00 s in steps of 0.01 s
Reset Delay: 0.0 to 6000.0 s in steps of 0.1 s
Signal Source: Voltage
Range: 10 to 65 Hz
Level Accuracy: ±0.02 V/Hz
Operate Time: Solid State Output: at 1.10 ×pickup: 165 to 195 ms
Relay Outputs 2-5: at 1.10 ×pickup: 170 to 200 ms (delay set to 0.0 s)
OVEREXCITATION ON 5TH HARMONIC LEVEL
Operating Current Pickup: 0.03 to 1.00 in steps of 0.01 ×CT
Pickup Level: 0.1 to 99.9 in steps of 0.1%
Dropout: 95% of pickup
Time Delay: 0 to 60000 s in steps of 1 s
Signal Source: All phase currents
Operate Time: Solid State Output: at 1.10 ×pickup: 20 to 120 ms
Relay Outputs 2-5: at 1.10 ×pickup: 25 to 125 ms (delay set at 0.0 s)
INSULATION AGING: HOTTEST-SPOT LIMIT
Pickup Level: 50 to 300 in steps of 1°C
Delay: 0 to 60000 in steps of 1 min.
INSULATION AGING: AGING FACTOR LIMIT
Pickup Level: 1.1 to 10.0 in steps of 0.1
Delay: 0 to 60000 in steps of 1 min.
INSULATION AGING: LOSS OF LIFE LIMIT
Pickup Level: 0 to 20000 in steps of 1 x 10 h