ABB REX 521, Technical Reference Manual, Standard Configurations

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1MRS751802-MUM Protection Relay
Technical Reference Manual, Standard Configurations
REX 521
Fig. 9.4.3.1.-2 Auto-reclose sequence, when AR is initiated by the trip signal.
The reclaim time is always started or restarted at a circuit breaker close operation. A
new initiation signal during the reclaim time will perform the next shot if such has
been selected. When all shots have been executed, the auto-recloser is locked out.
When the reclaim time has elapsed, the lock-out function of the auto-recloser ends,
if lock-out mode for the auto-recloser function has been set to "automatic".
To be able to initiate the auto-recloser function with the start or trip signal from a
protection function, a few settings must be prepared. The initiation signals from the
different protections can be found in
Main menu\Configuration\Input
SWGRP\
, where for example the overcurrent initiation signals are named as
O->I
\3I>…3I>>> .
To select the high overcurrent stage (3I>>) in order to initiate the auto-recloser
function, choose
O->I\3I>> . Press [E] push button and scroll the different
initiation signal methods with the [
→]
and
[←]
navigation push buttons. The
specific initiation method can be enabled or disabled with the [
↑]
and
[↓]
push
buttons. The checksum will be 1 if “3I>> Start AR1” is set and 2 if “3I>> Trip AR1”
is set.
After the initiation method is chosen, the settings for the auto-reclosure function has
to be made. In
Main menu\Protection\O->I\General setting\ the
operation is taken in use when the
AR operations
is set to ON and the
Reclaim
time
can be set.
The different shot settings are given in
Main menu\Protection\
O->I\Shot1…5 settings . To set the first shot as in the example above with
the initiation from the start:
1. Go to the Shot 1 setting.
2. Select Initiation mode as “Start”.
3. Select AR1 oper. mode as “Init Shot”.
4. Set the
AR1 start delay
to 0.1 s.
5. Set the Dead time to 0.3 s.
Proceed with the Shot 2 setting in the same way and with the start delay and dead-
time settings as in the example or as the functionality requires.
Start
AR1
(Trip signal
from protection)
Circuit breaker
Discrimination
Time
Close signal
Instant of fault
Protection
operation
time
Shot 1
Dead time
Shot 2
Dead time
Alarm
Definite Trip
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