GE Multilin 350 Series - Page 229

CHAPTER 6: SETPOINTS S3 PROTECTION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 6–113
Figure 38: Thermal model protection logic diagram
SETPOINTS
Phase A current (IA)
RUN
SETPOINT
THERMAL MDL FUNC Disabled = 0
Latched Alarm
THERMAL MDL PICKUP
AND
Phase B current (IB) Phase C current (IC)
Operate Output Relay 1 (TRIP)
LED: TRIP
Event Recorder
Transient Recorder
Alarm
OR
OR
Phase Currents
AND
SETPOINT:
Operate
output relays
upon
selection
OUTPUT RELAY 4 OUTPUT RELAY 5 OUTPUT RELAY 6 OUTPUT RELAY 3
Trip
AND
SETPOINT
BLOCK 1: Off=0 BLOCK 2: Off=0 BLOCK 3: Off=0
OR
Message
THERMAL
MODEL
Ph A Thermal OP
Ph B Thermal OP
Ph C Thermal OP
OR
Trip
HEATING T. CONSTANT COOLING T. CONSTANT
T
TRIP
(ph B)
T
TRIP
(ph C)
T
TRIP
(ph A)
Thermal Capacity ph A, % Thermal Capacity ph B, % Thermal Capacity ph C, %
ACTUAL VALUES
Ph A Thermal
Alarm
Message
OR
SETPOINT
THERMAL
MDL ALARM
ALARM
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Ph B Thermal Alarm
Ph C Thermal Alarm
LED: ALARM
RESET
Command
AND
S
R
LATCH
Event Recorder
Transient Recorder
898762.cdr
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