GE 889 - Page 275

CHAPTER 4: SETPOINTS PROTECTION
889 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL 4–145
Figure 4-51: Third Harmonic Neutral UV logic diagram
894139.cdr
3rd Harm VN in Sec
SETPOINT
Configurable
Trip Function
Disabled Trip
3 Phase Real Power
ACTUAL VALUES
SETPOINT
Block
Off=0
AND
Blocking Min Power
SETPOINTS
Max > Actual 3 Phase Real Power > Min
SETPOINT
Latched Alarm Alarm Function
Disabled
Alarm
OR
AND
RUN
Trip Pickup
SETPOINT
Trip Pickup Delay
SETPOINT
t
PKP
0
Alarm Pickup Delay
SETPOINT
t
PKP
0
AND
Operate Output
Relay 1(TRIP)
LED: TRIP
LED: Alarm
AND AND
OR
LATCH
S R
RESET
Command
3rd Ntr UV Trp PKP FLEXLOGIC OPERANDS 3rd Ntr UV Trp OP
3rd Ntr UV Alm PKP
FLEXLOGIC OPERANDS
3rd Ntr UV Alm OP
SETPOINT
Trip Output Relay
Do Not Operate, Operate
SETPOINT
Alarm Output Relay
Do Not Operate, Operate
OR
RUN
Alarm Pickup
SETPOINT
Blocking Max Power Blocking Low Voltage
SETPOINTS
|V_1| > Blocking Low Voltage
RUN RUN
OR
|3rd Harm VN| < Trip Pickup
ACTUAL VALUES
|3rd Harm VN|< Alarm Pickup
ACTUAL VALUES
V1
Metering/Ph VT Bnk1-J2/J2 V1
Metering/Power 1/Pwr1 Real
Third harmonic volt
metering of J-slot Vx