GE Multilin L60, Instruction Manual

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GE Multilin L60 Line Phase Comparison System 5-279
5 SETTINGS 5.6 CONTROL ELEMENTS
5
The
OPEN POLE REM CURR PKP
setting specifies pickup level for the remote-end current estimated by the relay as the local
current compensated by the calculated charging current. The latter is calculated based on the local voltages and the capac-
itive reactances of the line. This setting is relevant if open pole condition at the remote end of the line is to be sensed and
utilized by the relay (
OPEN POLE REM OP
FlexLogic operand).
The
OPEN POLE MODE
setting selects the mode of operation of the open pole function. When the “Accelerated” mode is cho-
sen, an open pole will be declared ½ cycle after trip output operation and before the breaker pole opens. This blocks dis-
tance loops involved in the faulted phase and phase selector, and arms the trip output to produce three-pole trip for the next
fault. If the fault evolves into multi-phase fault before breaker pole opens for the first fault, the remaining in-service distance
loops would initiate a three-pole trip. When the “Traditional” mode is selected, then an open pole is declared only after the
breaker opens and current disappears. If the fault evolves into a multi-phase fault before the circuit breaker pole opens for
the first fault, the phase selector will change the fault type from a single-line-to-ground fault to a multi-phase fault, thereby
initiating a three-pole trip.
The
OPEN POLE DETECTION
setting selects the signals used to detect an open pole condition. When “I AND V AND CBaux”
value is selected, the breaker 52 contacts and the current with optional voltage signals are used to determine open pole
conditions. For the “I AND V only” selection, only the current with optional voltage signals are used.
For convenience, the position of the breaker poles defined in the breaker control feature and available as FlexLogic oper-
and
BREAKER 1 Φ A CLSD
through
BREAKER 1 Φ C CLSD
and
BREAKER 1 OOS
are used by the open pole feature if the “I AND
V AND CBaux” detection value is selected.
For correct operation of the open pole detector, the breaker control, trip output, and single-pole autoreclose features must
be enabled and configured properly. When used in configuration with only one breaker, the
BREAKER 2 FUNCTION
should be
“Enabled” and the
BREAKER 2 OUT OF SV
setting should be “On” (refer to the Breaker Control section earlier in this chapter
for additional details).