Siemens UL 1066 - Reclosing a Circuit Breaker Tripped by the Trip Unit

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6.7 Reclosing a circuit breaker tripped by the trip unit
NOTE
The reason for tripping can be displayed using the "QUERY" button on the trip unit. This is stored for at least two days, provided that the
trip unit was activated for at least 10 minutes before tripping.
1
Find reason for
tripping
2
Indicator
Overload in
main conductor
Overload in neutral
conductor
Short circuit:
short-time-delay trip
Short circuit:
instantaneous trip
Ground fault trip
3
Find and rem-
edy cause
- Check downstream load
- Check trip unit settings
- Inspect switchgear
- Check downstream load
4
Inspect circuit
breaker
Inspect contact system for possible damage
 Maintenance (page 23-1)
5
Clear trip cause