GE D90 Plus Instruction Manual page 303

CHAPTER 7: PROTECTION
PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 234: Autoreclose scheme transfer logic
When the 1-2 reclosing sequence is selected and breaker 1 is blocked (the
operand is set) the reclose signal can be transferred direct to breaker 2 if the
setting is "Yes". If the setting is "No", the scheme will be sent to lockout by the incomplete
2
sequence timer.
When the 2-1 reclosing sequence is selected and breaker 2 is blocked (the
operand is set) the reclose signal can be transferred direct to breaker 1 if
setting is "Yes". If set to "No", the scheme will be sent to lockout by the incomplete
sequence timer or if it is out-of-service or open prior to the reclose-in-progress. In this case,
the scheme can be configured to transfer close command immediately to the second
breaker via the
Transfer 1 to 2
For two-breaker reclosing on a transient fault, the reset timer is started when the first
reclose output signal is sent to close breaker 1. The CLOSE BREAKER 1 signal initiates the
transfer timer that times out and sends the close signal to the second breaker. If the
reclosure sequence is successful (both breakers closed and there is no initiating signal), the
reset timer will time out and return the scheme to the reset state with the shot counter set
to 0. The scheme will now be ready for a new reclose cycle.
A typical reclosing sequence for the "1 & 3 Pole" mode is shown below for a single-pole
fault, two shots, with successful reclosure. The following two options are available if the
selected breaker sequence is "1–2" or "2–1", and the breaker fails to close after the first or
second reclose attempt.
• If the
Breaker 1 Failure Option
scheme will go to lockout state.
• If the
Breaker 1 Failure Option
reclose process will continue with breaker 2. At the same time, the shot counter will be
decreased (since the closing process was not completed).
and settings.
Transfer 2 to 1
or
Breaker 2 Failure Option
or
Breaker 2 Failure Option
CONTROL ELEMENTS
AR BKR1 BLK
Transfer 1 to
AR BKR2 BLK
Transfer 2 to 1
is set to "Lockout", the
is set to "Continue", the
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