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489 GENERATOR MANAGEMENT RELAY – INSTRUCTION MANUAL
CHAPTER 5: SETPOINTS
5.4.9
Field-Breaker
PATH: SETPOINTS
ZV
S3 DIGITAL INPUTS
ZV
FIELD-BREAKER DISCREPANCY
If an input is assigned to the tachometer function, it may not be used here.
The field-breaker discrepancy function is intended for use with synchronous generators. If
a digital input is assigned to this function, any time the field status contact indicates the
field is not applied and the breaker status input indicates that the generator is online, a trip
will occur once the time delay has expired. The time delay should be used to prevent
possible nuisance tripping during shutdown. The field status contact may be chosen as
“Auxiliary a”, open signifying the field breaker or contactor is open and shorted signifying
the field breaker or contactor is closed. Conversely, the field status contact may be chosen
as “Auxiliary b”, shorted signifying the field breaker or contactor is open and open
signifying it is closed.
5.4.10 Tachometer
PATH: SETPOINTS
ZV
S3 DIGITAL INPUTS
ZV
TACHOMETER
FIELD-
BREAKER
[
Z
]
ASSIGN DIGITAL
INPUT: None
Range: None, Input 1 to Input 7
MESSAGE
FIELD STATUS
CONTACT: Auxiliary a
Range: Auxiliary a, Auxiliary b
MESSAGE
ASSIGN TRIP
RELAYS (1-4): 1---
Range: Any combination of Relays 1 to
4
MESSAGE
FIELD-BKR DISCREP.
TRIP DELAY: 1.0 s
Range: 0.1 to 500.0 s in steps of 0.1
TACHOMETER
[
Z
]
ASSIGN DIGITAL
INPUT: None
Range: None, Inputs 4 to 7.
MESSAGE
RATED SPEED:
3600 RPM
Range: 100 to 3600 RPM in steps of 1
MESSAGE
TACHOMETER
ALARM: Off
Range: Off, Latched, Unlatched
MESSAGE
ASSIGN ALARM
RELAYS (2-5): ---5
Range: Any combination of Relays 2 to
5
MESSAGE
TACHOMETER ALARM
SPEED: 110% Rated
Range: 101 to 175% in steps of 1
MESSAGE
TACHOMETER ALARM
DELAY: 1 s
Range: 1 to 250 s in steps of 1
MESSAGE
TACHOMETER ALARM
EVENTS: Off
Range: On, Off
MESSAGE
TACHOMETER
TRIP: Off
Range: Off, Latched, Unlatched
MESSAGE
ASSIGN TRIP
RELAYS (1-4): 1---
Range: Any combination of Relays 1 to
4