GE 889 - Page 431

CHAPTER 4: SETPOINTS MONITORING
889 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL 4–301
Figure 4-124: Power Factor logic diagram
894171A1.cdr
SETPOINT
Configurable Trip Function
Disabled
Trip
SETPOINT
Block
Off=0
AND
SETPOINT
Latched Alarm Alarm Function
Disabled Alarm
OR
AND
RUN
Trip Lag Level
SETPOINT
Trip Pickup Delay
SETPOINTS
Trip Dropout Delay
t
PKP
t
RST
Alarm Pickup Delay
SETPOINTS
Alarm Dropout Delay t
PKP
t
RST
AND
Operate Output
Relay 1(TRIP)
LED: TRIP
LED: Alarm
AND AND
OR
LATCH
S R
RESET
Command
PF Trip PKP
FLEXLOGIC OPERANDS
PF Trip OP
PF Alarm PKP
FLEXLOGIC OPERANDS
PF Alarm OP
SETPOINT
Trip Output Relay X
Do Not Operate, Operate
SETPOINT
Alarm Output Relay X
Do Not Operate, Operate
OR
when PF < 0 & |PF| < Trip Lead Level
OR
Trip Lead Level
Voltage Inputs
- delta connected
VAB VBC VCA
Current Inputs
Phase A Current (IA) Phase B Current (IB) Phase C Current (IC)
SETPOINTS
MINIMUM VOLTAGE: VAB ≥ MINIMUM
IA ≥ MINIMUM
VBC ≥ MINIMUM VCA ≥ MINIMUM
IB ≥ MINIMUM IC ≥ MINIMUM
AND OR
Voltage Inputs
- wye connected
VA VB VC
VA ≥ MINIMUM VB ≥ MINIMUM VC ≥ MINIMUM
AND AND AND
AND
OR
OR
Power Factor of Three Phases (delta-connected VTs) Power Factor of Valid Phase(s) (wye-connected VTs)
when PF > 0 & |PF| < Trip Lag Level
RUN
Alarm Lag Level
SETPOINT
when PF < 0 & |PF| < Alarm Lead Level
OR
Alarm Lead Level
when PF > 0 & |PF| < Alarm Lag Level
MINIMUM CURRENT: