Panels with motor operating mechanism control
236
NXAIR M
139-2021.9 / 07
23.20 Fault indication and fault evaluation
A fault will always shut down the associated motor operating mechanism, and can be issued as a fault
indication when a SIPROTEC relay is installed. The fault is generally reset by switching the auxiliary voltage
off and on again.
For several fault outputs, the fault signal is reset automatically or by certain actions.
Type of fault
Reverse interlocking
to circuit-breaker
Cause / Remedy
Motor voltage is not switched on
On
Check MCB or wiring
Motor voltage is not switched off
On
Motor voltage relay in motor control
unit defective
No feedback of auxiliary switch
during command “rack withdrawable
circuit-
breaker” to service position
On
Check operating mechanism or motor
with respect to blocking
1)
No feedback of auxiliary switch
during command “rack withdrawable
circuit-
breaker to test position”
On
Check operating mechanism or motor
with respect to blocking
1)
No automatic shutdown after end of
command
On
Circuit for automatic shutdown in
motor control unit defective
High-voltage door is open while the
withdrawable circuit-breaker is being
racked
On
Operating mechanism stops
The withdrawable circuit-breaker is
racked and stops in an intermediate
position when the motor voltage fails
On
When the motor voltage is switched on
again, the withdrawable circuit-breaker
can be racked to a valid end position
by hand. Then, the fault is reset.
The auxiliary voltage and the motor
voltage fail while racking. The
auxiliary switch does not report a
valid end position
On
When the auxiliary voltage and motor
voltage are switched on again, the
fault can be reset by manual operation
to a valid end position.
1)
This fault signal can be reset
