GE Multilin 850

CHAPTER 4: SETPOINTS CONTROL
850 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 4–349
Figure 4-154: Undervoltage Restoration logic diagram
894069A3.cdr
LED: PICKUP
SETPOINTS
FUNCTION:
OR
t
PKP
0
Ph UV Restore OP
AND AND
Command
RESET
OR
LED: ALARM
SETPOINTS
BLOCK: Off=0
AND
OR
OR
AND
AND
Command
RESET
SETPOINTS
INCOMPLETE SEQUENCE TIME: t
IST
0
Status Input
BKR 1 Open
Bus voltage Inputs
Line voltage input
WYE DELTA
VA (VAB) VA B VB (VBC)
VBC
VC (VCA) VCA Vx
SETPOINTS
UV RESTORE MINIMUM VOLTAGE: VA(VAB)

MINIMUM
RUN UV RESTORE RESTORE DELAY:
AND
t
PKP
0
VB(VBC)

MINIMUM
RUN
t
PKP
0
VC(VCA)

MINIMUM
RUN
t
PKP
0
Vx

MINIMUM
RUN
AND
SETPOINTS
UV RESTORE PHASES FOR OPERATION: OPERATE:
ANY ONE ALL THREE ANY TWO
PICKUP:
ANY ONE ALL THREE ANY TWO
OR
Ph UV Restore PKP
Aux UV Restore OP
FlexLogic Operands
S
LATCH
Set-
Dominant
R
SETPOINTS
Phase UV 1 OP Phase UV 2 OP Aux UV 1 OP Aux UV 2 OP
OR
OR
Aux UV Restore PKP
OR
OR
Disabled Alarm Latched Alarm Configurable
Close
AND
INITIATION:
OR
OR
SETPOINTS
OUTPUT RELAYS (3 -7): Do Not Operate, Operate
UV Restore Init
AND
from BKR1 Status
FlexLogic Operand
BKR 1 Closed
FlexLogic Operand
BKR 1 Closed
The Voltage Input is the same as the one used for UV element
programmed under
³
UF Restore initiation
´
to BKR1 Close Relay
Select output relay
SETPOINT
SYNCHROCHECK
SUPERVISION:
Bypass
Sync1 Close Perm
Sync1 Close Perm
From Synchrocheck 1
ANDAND
OR
Sync2 Close Perm
From Synchrocheck 2
ANDAND
Sync2 Close Perm