Siemens siprotec 7SA6, Manual

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Installation and Commissioning
8-58
7SA6 Manual
C53000-G1176-C156-2
The surrounding circuit breakers are all those which need to trip when the feeder cir-
cuit breaker fails. These are therefore the circuit breakers of all feeders which feed the
busbar or busbar section to which the feeder with the fault is connected.
A general detailed test guide cannot be specified because the layout of the surround-
ing circuit breakers largely depends on the switchgear topology.
In particular with multiple busbars the trip distribution logic for the surrounding circuit
breakers must be checked. Here it should be checked for every busbar section that all
circuit breakers which are connected to the same busbar section as the feeder circuit
breaker under observation are tripped, and no other breakers.
Tripping of the
Remote End If the trip command of the circuit breaker failure protection must also trip the circuit
breaker at the remote end of the feeder under observation, the transmission channel
for this remote trip must also be checked. This is done together with transmission of
other signals according to section 8.3.13.3.
Termination All temporary measures taken for testing must be undone, e.g. especially switching
states, interrupted trip commands, changes to setting values or individually switched
off protection functions.