GE UR Series C70 Instruction Manual page 251

5 SETTINGS
• CUR UNBALCE 1 STG 1A PICKUP to CUR UNBALCE 1 STG 4C PICKUP: These settings specify pickup thresholds
for stages 1 through 4 in phases A through C in per-units (pu) of the nominal current of the differential source. A value
of 1 pu is the nominal secondary current, or the nominal primary current, respectively, as configured under the differen-
tial source of this function.
• CUR UNBALCE 1 STG 1 PKP DELAY to CUR UNBALCE 1 STG 4 PKP DELAY: This setting specifies the pickup
time delay, individually per each stage of alarming/tripping. Note that each of the twelve comparators (four stages in
three phases) uses an individual timer, but settings for these timers are controlled individually per each stage, not per
phase. The timers use a common drop out time delay specified by the next setting.
• CUR UNBALCE 1 DPO DELAY: This setting controls a drop out delay for the operate FlexLogic™ operands. Note that
individual stages apply individually configurable pickup delays, but use this common drop out delay.
• CUR UNBL 1 BLK STG1 to CUR UNBL 1 BLK STG4: These settings are used to block the function on a per-stage
basis when required. At minimum this function shall be blocked when the two banks are not paralleled. Note that when
unblocked, the function becomes operational after five cycles of intentional delay. High-set instantaneous protection on
energization can be provided by a separate instantaneous overcurrent function.
SETTINGS
CUR UNBL 1 BLK STG1:
Off = 0
INHIBIT STAGE 1
CUR UNBL 1 BLK STG2:
Off = 0
INHIBIT STAGE 2
CUR UNBL 1 BLK STG3:
Off = 0
INHIBIT STAGE 3
CUR UNBL 1 BLK STG4:
Off = 0 INHIBIT STAGE 4
CUR UNBALCE 1
FUNCTION:
Enabled = 1
IA_mag > 0.25pu
IB_mag > 0.25pu
IC_mag > 0.25pu
SETTINGS
SETTINGS
CUR UNBALCE 1
BANK SOURCE:
CUR UNBALCE 1
INHNT FACTOR A:
PHASE CT "None" = 0
IA
IB
IC
CUR UNBALCE 1 DIF
SOURCE:
IA_dif
IB_dif
IC_dif
PHASE B
PHASE C
Figure 5–57: PHASE CURRENT UNBALANCE SCHEME LOGIC
GE Multilin
TIMER
5 cycles
RUN 60P FUNCTION
0
SETTING
COMMANDS/ CUR
COMMANDS
UNBALACE 1 AUTO-
SETTING:
AUTO-SETTING
Auto
PROCEDURE
Manual
Apply?
WRITE A NEW SETTING
SETTING
CUR UNBALCE 1 STG
1A PICKUP:
RUN RUN
IA_op > PICKUP
SETTING
CUR UNBALCE 1 STG
2A PICKUP:
RUN
IA_op > PICKUP
SETTING
CUR UNBALCE 1 STG
3A PICKUP:
RUN
IA_op > PICKUP
SETTING
CUR UNBALCE 1 STG
4A PICKUP:
RUN
IA_op > PICKUP
C70 Capacitor Bank Protection and Control System
5.6 GROUPED ELEMENTS
TIMERS
CUR UNBALCE 1 DPO
DELAY:
CUR UNBALCE 1 STG
1 PKP DELAY:
FLEXLOGIC OPERAND
t
PKP
CUR BAL 1 STG 1A PKP
t
DPO
CUR UNBALCE 1 STG
2 PKP DELAY:
FLEXLOGIC OPERAND
t
PKP
CUR BAL 1 STG 2A PKP
t
DPO
CUR UNBALCE 1 STG
3 PKP DELAY:
FLEXLOGIC OPERAND
t PKP
CUR BAL 1 STG 3A PKP
t
DPO
CUR UNBALCE 1 STG
4 PKP DELAY:
FLEXLOGIC OPERAND t
PKP
CUR BAL 1 STG 4A PKP
t
DPO
FLEXLOGIC OPERANDS
CUR BAL 1 PKP A
CUR BAL 1 PKP B
CUR BAL 1 PKP C
FLEXLOGIC OPERAND
CUR BAL 1 PKP
CUR BAL 1 DPO
5
FLEXLOGIC OPERAND
CUR BAL 1 STG 1A OP
FLEXLOGIC OPERAND
CUR BAL 1 STG 2A OP
FLEXLOGIC OPERAND
CUR BAL 1 STG 3A OP
FLEXLOGIC OPERAND
CUR BAL 1 STG 4A OP
FLEXLOGIC OPERANDS
CUR BAL 1 OP A
CUR BAL 1 OP B
CUR BAL 1 OP C
FLEXLOGIC OPERAND
CUR BAL 1 OP
834729A2.CDR
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