GE Multilin 850

CHAPTER 4: SETPOINTS CONTROL
850 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 4–347
PHASES FOR OPERATION
Range: Any one, Any Two, All Three
Default: All Three
The setting defines the number of voltages required for operation of the Undervoltage
Restoration function. The setpoint is seen only if INITIATION is “PHASE UV 1 OP” or
“PHASE UV 2 OP”.
MINIMUM VOLTAGE
Range: 0.000 to 1.250 x VT in steps of 0.001 x VT
Default: 0.900 x VT
The setting sets the minimum voltage for Undervoltage Restoration element operation
specified per times VT.
FAST PATH:
The minimum voltage used here applies to the voltage input programmed under the Signal
Input setpoint of the element used for UV Restore Initiation. For example, if Phase UV 1 OP
is used for initiation for the UV Restore 1 scheme, the minimum voltage setting value will
apply to the voltage (Selected VT bank) programmed under Signal Input setpoint from
‘Phase Undervoltage 1’ element menu.
RESTORE DELAY
Range: 0.000 to 6000.000 s in steps of 0.001 s
Default: 10.000 s
The setting provides a definite restore time delay. Instantaneous operation is selected
by a restore time delay setting of 0.000 s.
INCOMPLETE SEQUENCE TIME
Range: 1 to 10000 min in steps of 1 min
Default: 100 min
The setting provides a definite reset time delay.
SYNCHROCHECK SUPERVISION
Range: Bypass, Sync 1 Cls Perm, Sync 2 Cls Perm
Default: Bypass
The setpoint selects Synchrocheck supervision. The closing signal (for output #2 only)
from the UV Restore function can be supervised by the Synchrocheck function. The
Synchrocheck function has to be enabled and set accordingly. For applications where
Synchrocheck and/or dead source check is not needed, supervision can be bypassed. If
the Synchrocheck function is not selected in the order code, this setting would be hidden
and defaulted to Bypass.
FAST PATH:
If the supervision is not bypassed and UV Restore is applied for an application where the
breaker is located on radial feeders, or line is powered by one source only, the DEAD
SOURCE PERM setpoint from the Synchrocheck menu shall not be disabled.
FAST PATH:
A Synchrocheck supervised UV Restore CLOSE command is sent directly to output #2. For
other outputs, logic has to be created for supervision as required.
BLOCK
Range: Off, Any FlexLogic operand
Default: Off
OUTPUT RELAY X
For details see Common Setpoints
.
EVENTS
Range: Disabled, Enabled
Default: Enabled