GE 489 - Manual (Page 90)

4-40 489 Generator Management Relay GE Multilin
4.7 S6 VOLTAGE ELEMENTS 4 SETPOINTS
4
Figure 4–6: NEUTRAL OVERVOLTAGE DETECTION
If the ground directional element is enabled, the Neutral Overvoltage element should be coordinated with it. In
cases of paralleled generator grounds through the same point, with individual ground switches, per sketch below, it
is recommended to use a ground switch status function to prevent maloperation of the element.
4.7.8 NEUTRAL OVERVOLTAGE (3RD HARMONIC)
PATH: SETPOINTS ÖØ S6 VOLTAGE ELEMENTS ÖØ NEUTRAL U/V (3RD)
„ NEUTRAL U/V (3rd)
„ [ENTER] for more
LOW POWER BLOCKING
LEVEL: 0.05 x Rated MW
Range: 0.02 to 0.99 × Rated MW in steps of 0.01
Seen only if VT CONNECTION is "Delta"
LOW VOLTAGE BLOCKING
LEVEL: 0.75 x Rated
Range: 0.50 to 1.00 × Rated in steps of 0.01
Seen only if VT CONNECTION is "Delta"
NEUTRAL UNDERVOLTAGE
ALARM: Off
Range: Off, Latched, Unlatched
ASSIGN ALARM
RELAYS (2-5): ---5
Range: Any combination of Relays 2 to 5
NEUTRAL U/V ALARM
LEVEL: 0.5 Vsec
Range: 0.5 to 20.0 Vsec in steps of 0.1
Seen only if VT CONNECTION is "Delta"
NEUTRAL UNDERVOLTAGE
ALARM DELAY: 30 s
Range: 5 to 120 s in steps of 1
NEUTRAL UNDERVOLTAGE
ALARM EVENTS: Off
Range: On, Off
NEUTRAL UNDERVOLTAGE
TRIP: Off
Range: Off, Latched, Unlatched
ASSIGN TRIP
RELAYS (1-4): 1---
Range: Any combination of Relays 1 to 4
NEUTRAL U/V TRIP
LEVEL: 1.0 Vsec
Range: 0.5 to 20.0 Vsec in steps of 0.1
Seen only if VT CONNECTION is "Delta"
NEUTRAL UNDERVOLTAGE
TRIP DELAY: 30 s
Range: 5 to 120 s in steps of 1
59G
A A
C(B) C(B)
B(C)
GENERATOR 1 GENERATOR 2
B(C)
TO Vneutral OF EACH 489
AUXILIARY CONTACT
TO DIGITAL INPUT FOR
NEUTRAL O/V SUPERVISION
GROUNDING SWITCH
808816A3.CDR
NOTE
ENTER
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