GE Multilin 850

CHAPTER 4: SETPOINTS CONTROL
850 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 4–345
Figure 4-153: Cold Load Pickup logic diagram
894068A2.cdr
COMPARATORS
SETPOINTS
COLD LOAD PICKUP FUNCTION: Disabled Alarm
OR
OR
AND
Latched Alarm
LED: ALARM /
LATCHED ALARM
RESET
Command
AND
S R
LATCH # 1
Set-
Dominant
Configurable
FlexLogic Operand
Cold Load 1 OP
t
OUT
0
SETPOINTS
Do Not Operate, Operate OUTPUT RELAYS 3 to 7
IA < 0.05 p.u. IB < 0.05 p.u.
IC < 0.05 p.u.
Phase B current (IB) Phase C current (IC)
RUN RUN RUN
AND
SETPOINTS
COLD LOAD PICKUP BLOCK : Off = 0
AND
Phase A current (IA)
SETPOINTS
OUTAGE T BEFORE COLD LOAD:
AND
OR
SETPOINTS
EXTERNAL INITIATION : Off = 0
OR
COMPARATORS
IA > 0.05 p.u. IB > 0.05 p.u.
IC > 0.05 p.u.
RUN RUN RUN
OR
SETPOINTS
COLD LOAD T BEFORE RESET
AND
To
TOC Pickup Raise, IOC
Blocking and Setting
Group Change
AND
FlexLogic Operand
Cold Load 1 PKP
t
RST
0
SETPOINTS
SIGNAL INPUT: CT Bank 1 - J1
FLEXLOGIC OPERAND
AR 1 DISABLED