21/07/2010
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MRAR 01/96 C
5.3.6 Successful Reclosing
If there is no OFF signal to the circuit breaker and no protection tripping signal within the Reclaim Time
then a successful reclosing has taken place. The unit now changes from the Cycle state to the Ready
state and the O
→
I LED indicates green signalling a successful reclosing. The LED display can be reset
by pressing and holding the <SELECT/RESET> button for 5 seconds.
5.3.7 Repeated Reclosing
If the MRAR is programmed for more than single shot reclosing a second Dead Time is started after a
new OFF signal to the circuit breaker. After this period a new switch on command follows.
5.3.8 External Blocking and Reseting
The unit is blocked from further reclosing attempts when an external blocking signal is applied to
terminal 24. This is independant of whatever state the MRAR is in at the time. This blocking signal can
only be revoked by the applying of a reset signal to terminal 25.
5.3.9 Supervision of the Circuit Breaker Ready Information
Because the supervision of the circuit breaker energy store responds often after the first fast switch off
(see para. 4.1.1), the signal, AR Not Ready, is not evaluated after a reclosing. The readiness of the
switch is checked before an auto-reclosing and then after the first unsuccessful attempt of auto-reclosing
thereafter. There will be reclosing when the circuit breaker indicates readiness before the beginning of
the switching cycle.
5.4 Operation and Release of the Output Relays
Close Circuit Breaker Relay (31, 29, 33 and 32, 30, 34)
Operation:
At the end of the Dead Time (tD) when all closing conditions are fulfilled.
Release:
When the circuit breaker is switched on or when the closing Impulse Time (tC)
has expired.
High Set Blocking Relay (38, 36, 40 and 37,35,39)
Operation:
When the unit is in the Ready State.
Release:
Simultaneously with the first reclosing command.
Alarm AR in Progress Relay (43, 41, 45 and 44,42,46)
Operation:
When the MRAR is started.
Release:
When all AR cycles are terminated.
