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745 Transformer Management Relay
GE Multilin
TABLE OF CONTENTS
7.2.6
CRC-16 ALGORITHM ........................................................................................7-4
7.2.7
MESSAGE TIMING ............................................................................................7-4
7.3 MODBUS FUNCTIONS
7.3.1
SUPPORTED MODBUS FUNCTIONS...............................................................7-5
7.3.2
EXCEPTION RESPONSES................................................................................7-8
7.3.3
READING THE EVENT RECORDER.................................................................7-8
7.3.4
READING TRACE MEMORY .............................................................................7-9
7.3.5
ACCESSING DATA VIA THE USER MAP .........................................................7-9
7.3.6
FUNCTION CODE SUBSTITUTIONS ..............................................................7-11
7.3.7
MEMORY MAP ORGANIZATION.....................................................................7-12
7.4 MODBUS MEMORY MAP
7.4.1
745 MEMORY MAP..........................................................................................7-13
7.4.2
MEMORY MAP DATA FORMATS....................................................................7-48
7.5 DNP COMMUNICATIONS
7.5.1
DEVICE PROFILE DOCUMENT ......................................................................7-61
7.5.2
IMPLEMENTATION TABLE .............................................................................7-63
7.5.3
DNP POINT LISTS ...........................................................................................7-64
8. COMMISSIONING
8.1 GENERAL
8.1.1
INTRODUCTION ................................................................................................8-1
8.1.2
TESTING PHILOSOPHY....................................................................................8-1
8.1.3
SAFETY PRECAUTIONS...................................................................................8-2
8.1.4
CONVENTIONS .................................................................................................8-2
8.1.5
TEST EQUIPMENT ............................................................................................8-3
8.2 PRELIMINARY WORK
8.2.1
DESCRIPTION ...................................................................................................8-4
8.2.2
DIELECTRIC STRENGTH TESTING .................................................................8-5
8.3 LOGIC INPUTS AND OUTPUT RELAYS
8.3.1
LOGIC INPUTS ..................................................................................................8-6
8.3.2
OUTPUT RELAYS..............................................................................................8-6
8.4 DISPLAY, METERING, COMMUNICATIONS, AND ANALOG OUTPUTS
8.4.1
DESCRIPTION ...................................................................................................8-7
8.4.2
CURRENT INPUTS ............................................................................................8-7
8.4.3
VOLTAGE INPUT ...............................................................................................8-8
8.4.4
TRANSFORMER TYPE SELECTION ................................................................8-8
8.4.5
AMBIENT TEMPERATURE INPUT ....................................................................8-9
8.4.6
ANALOG OUTPUTS.........................................................................................8-11
8.4.7
TAP POSITION.................................................................................................8-11
8.5 PROTECTION SCHEMES
8.5.1
PRECAUTIONS................................................................................................8-12
8.5.2
HARMONIC RESTRAINED PERCENT DIFFERENTIAL .................................8-12
8.5.3
INSTANTANEOUS DIFFERENTIAL PROTECTION ........................................8-17
8.5.4
PHASE TIME OVERCURRENT .......................................................................8-17
8.5.5
PHASE INSTANTANEOUS OVERCURRENT .................................................8-19
8.5.6
NEUTRAL TIME OVERCURRENT...................................................................8-20
8.5.7
NEUTRAL INSTANTANEOUS OVERCURRENT.............................................8-21
8.5.8
GROUND TIME OVERCURRENT....................................................................8-22
8.5.9
GROUND INSTANTANEOUS OVERCURRENT..............................................8-24
8.5.10 RESTRICTED GROUND FAULT......................................................................8-25
8.5.11 NEGATIVE SEQUENCE TIME OVERCURRENT ............................................8-27
8.5.12 NEGATIVE SEQUENCE INSTANTANEOUS OVERCURRENT ......................8-28
8.5.13 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
