2.20 Function control and circuit breaker testing
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7SA522 Manual
C53000-G1176-C155-3
Figure 2-156 Breaker tripping alarm suppression — sequence examples
Trip Dependent
Messages
The latching of messages allocated to local LEDs, and the storage of spontaneous
messages can be made dependent on whether the device has issued a trip command.
This information is then not output if during a system disturbance one or more protec-
tion functions have picked up, but no tripping by the 7SA522 resulted because the fault
was cleared by a different device (e.g. on another line). These messages are then
limited to faults in the line to be protected.
Figure 2-157 Logic diagram of the no–trip–no–flag feature (command-dependent alarms)
Statistics The number of trips initiated by the device 7SA522 are counted. If the device is
capable of single-pole tripping, a separate counter for each circuit breaker pole is pro-
vided.
Following each trip command the device registers the value of each current phase that
was switched off in each pole. This information is then provided in the trip log and sum-
mated in a register. The maximum current that was switched off is also stored.
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