2 Functions
342
7SA522 Manual
C53000-G1176-C155-3
Breaker Tripping
Alarm Suppression
While on feeder without automatic reclosure every trip command by a protection func-
tion is final, it is desirable, when using automatic reclosure, to prevent the operation
detector of the circuit-breaker (transient contact on the breaker) from sending an alarm
if the trip of the breaker is not final (Figure 2-155).
For this purpose, the signal from the circuit-breaker is routed via a correspondingly al-
located output contact of the 7SA522 (output alarm ´&%$ODUP6XSSµ, FNo. 563).
In the idle state and when the device is turned off, this contact is closed continuosly.
Therefore an output contact with a normally closed contact has to be allocated. Which
contact is to be allocated is dependent on the device version. Refer to the general
views in the Appendix.
Prior to the command, with the internal automatic reclosure in the ready state, the
contact opens so that no signal from the circuit-breaker is forwarded. This is only the
case if the device is equipped with internal automatic reclosure and if the latter was
taken into consideration when configuring the protection functions (address ).
Also when closing the breaker via the binary input ´!0DQXDO&ORVHµ (FNo. 356) or
via the integrated automatic reclosure the contact is interrupted so that the breaker
alarm is inhibited.
Further optional closing commands which are not sent via the device cannot be taken
into consideration. Closing commands for control can be linked to the alarm suppres-
sion via the user-defined logic functions (CFC).
Figure 2-155 Breaker tripping alarm suppression
If the device issues a final trip command, the contact remains closed. This is the case,
during the reclaim time of the automatic reclosure cycle, when the automatic reclosure
is blocked or switched off or, due to other reasons is not ready for automatic reclosure
(e.g. tripping only occurred after the action time expired).
Figure 2-156 shows time diagrams for manual trip and close as well as for short-circuit
tripping with a single, failed automatic reclosure cycle.
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