Distance Elements - GE 489 Instruction Manual

4 SETPOINT PROGRAMMING
T
DISTANCE ELEMENT
T
[ENTER] for more
The distance protection function (ANSI device 21) implements two zones of mho phase-to-phase distance protection (six
elements total) using the conventional phase comparator approach, with the polarizing voltage derived from the pre-fault
positive sequence voltage of the protected loop. This protection is intended as backup for the primary line protection. The
elements make use of the neutral-end current signals and the generator terminal voltage signals (see figure below), thus
providing some protection for internal and unit transformer faults. In systems with a delta-wye transformer (DY330°), the
appropriate transformations of voltage and current signals are implemented internally to allow proper detection of trans-
GE Power Management
Figure 4–7: LOSS OF EXCITATION R-X DIAGRAM
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STEP UP TRANSFORMER
ENTER
SETUP: None
ESCAPE
FUSE FAILURE
ESCAPE
SUPERVISION: On
MESSAGE
ZONE #1
ESCAPE
TRIP: Off
MESSAGE
ASSIGN ZONE #1 TRIP
ESCAPE
RELAYS (1-4): 1---
MESSAGE
ZONE #1
ESCAPE
REACH: 10.0 Ωsec
MESSAGE
ZONE #1
ESCAPE
ANGLE: 75°
MESSAGE
ZONE #1 TRIP
ESCAPE
DELAY: 0.4 s
MESSAGE
ZONE #2
ESCAPE
TRIP: Off
MESSAGE
ASSIGN ZONE #2 TRIP
ESCAPE
RELAYS (1-4): 1---
MESSAGE
ZONE #2
ESCAPE
REACH: 15.0 Ωsec
MESSAGE
ZONE #2
ESCAPE
ANGLE: 75°
MESSAGE
ZONE #2 TRIP
ESCAPE
DELAY: 2.0 s
MESSAGE
489 Generator Management Relay
4.7 S6 VOLTAGE ELEMENTS

4.7.10 DISTANCE ELEMENTS

Range: None, Delta/Wye
Range: On, Off
Range: Off, Latched, Unlatched
Range: Any combination of Relays 1 to 4
Range: 0.1 to 500.0 Ωsec in steps of 0.1
Range: 50 to 85° in steps of 1
Range: 0.0 to 150.0 s in steps of 0.1
Range: Off, Latched, Unlatched
Range: Any combination of Relays 1 to 4
Range: 0.1 to 500.0 Ωsec in steps of 0.1
Range: 50 to 85° in steps of 1
Range: 0.0 to 150.0 s in steps of 0.1
4
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