GE 845 - Page 278

4–150 845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
PROTECTION CHAPTER 4: SETPOINTS
894021A1.CDR
SETPOINT
Ia Diff 2nd Harm
MINIMUM PICKUP:
AND
Ib Diff 2nd Harm
Ic Diff 2nd Harm
Differential 2nd Harmonic
SETPOINT:
OUTPUT RELAY 1(X),
upon selection
SETPOINT
BLOCK
Off = 0
Phase A Diff current (Ia Diff )
Phase B Diff current (Ib Diff)
Phase C Diff current (Ic Diff )
Differential Currents
Phase A Rest current (Ia Restr )
Phase B Rest current (Ib Restr )
Phase C Rest current (Ic Restr )
Restraint Currents
SETPOINT
INRUSH INHIBIT
Disabled = 0
2nd Harm Block
Slope 1
Break 1
Break 2
Slope 2
RUN
RUN
RUN
INRUSH INHIBIT MODE
INRUSH INHIBIT LEVEL
Ia Diff 2nd Harm ≥ LEVEL
Ib Diff 2nd Harm ≥ LEVEL
SETPOINT
Ic Diff 2nd Harm ≥ LEVEL
RUN
RUN
SETPOINT
OVEREXCITATION
INHIBIT
Disabled = 0
5th Harm Block
Ia Diff 5th Harm
Ia Diff 5th Harm
Ia Diff 5th Harm
Differential 5th Harmonic
OVEREXC. INHIBIT LEVEL
Ia Diff 5th Harm ≥ LEVEL
Ib Diff 5th Harm ≥ LEVEL
SETPOINT
Ic Diff 5th Harm ≥ LEVEL
RUN
RUN
RUN
AND
AND
AND
LED: PICKUP
OR
RUN
2nd Harm Diff A
2nd Harm Diff B
2nd Harm Diff C
5th Harm Diff A
5th Harm Diff B
5th Harm Diff C
SETPOINTS
FUNCTION:
Disabled = 0
Trip
OR
OR
AND AND
LED: ALARM
AND
S
R
LATCH
Configurable
LED: TRIP
RESET
Command
Set Dominant
Do Not Operate, Operate
r
d
(Ia Diff /
Ia Restr ) >
r
d
(Ib Diff /
Ib Restr) >
(Ic Diff /
Ic Restr) >
r
d
I
ad
>(0.5 x PKP)
I
bd
>(0.5 x PKP)
I
cd
>(0.5 x PKP)
OR
Percent Diff Warn
10s
0s
FlexLogic Operands
OR
Pcnt Diff Blocked
SETPOINTS
INSTANTANEOUS DIFF
FUNCTION:
Disabled = 0
Trip
Alarm
Latched Alarm
Configurable
OR
AND
SETPOINT
INST DIFF BLOCK:
Off = 0
|Iad| > Pickup
RUN
SETPOINT
INST DIFF PICKUP:
|Ibd| > Pickup
|Icd| > Pickup
RUN
RUN
OR
Instant Diff OP C
Instant Diff OP
Instant Diff OP B
Instant Diff OP A
FlexLogic Operands
OR
OR
OR OR OR
Percent Diff Sat C
FlexLogic Operands
Percent Diff Dir C
OR
Percent Diff Sat B
FlexLogic Operands
Percent Diff Dir B
OR
Percent Diff Sat A
FlexLogic Operands
Percent Diff Dir A
OR
AND
Tpkp
0
Tpkp
0
Tpkp
0
SETPOINT
SETPOINT
SETPOINT
AND AND
OR
Percent Diff OP A
Percent Diff OP B
Percent Diff OP C
Percent Diff OP
OR
Percent Diff PKP A
Percent Diff PKP B
Percent Diff PKP C
Percent Diff PKP
FlexLogic Operands