Siemens SINAMICS PERFECT HARMONY GH150 6SL3826, Operating Instructions Manual

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This means that the drive can still continue to operate even if a ground impedance or resistance
occurs anywhere in the motor, motor feeder cables, GH150 inverter, the basic infeed rectifier
and/or the secondary sections of the supply transformer.
SINAMICS GH150 detects the signal, and the sensitivity can be adjusted.
Ground faults such as these must be detected for safety reasons.
When a ground fault occurs, an alarm is displayed to the customer. The alarm can also be
configured as a fault.
This system is only operational if the DC link and the BLM are under voltage (live).
The system does not use any current injected from a pulse source, which must be shut
down. As a consequence, the ground fault detection system does not have to be shut down
when the GH150 is in maintenance.
8.3.1.2 Tripping of the circuit-breaker in case of undervoltage
If a serious fault occurs (e.g. overload in the DC link), the drive is immediately disconnected
from the power supply using the safety shutdown function.
WARNING
Danger to life as a result of residual voltages at the output terminals
This function cannot ensure that the drive stops immediately, nor can it ensure that residual
voltages do not still exist at the output terminals and within the device itself.
High voltages can cause death or serious injury if the safety rules are not observed or if the
equipment is handled incorrectly.
● Always carefully observe the "five safety rules (Page 13)".
The shutdown of the circuit-breaker is triggered by a safety contactor combination.
The plant-side circuit-breaker must be equipped with an undervoltage trip to ensure the wire-
break protection for the circuit-breaker OFF command. If a circuit-breaker OFF command is
issued as a result of an overvoltage trip, the circuit-breaker is switched off so that it is fail-safe.
8.3.1.3 Automatic restart
After the power fails and returns, the drive is automatically switched on again, irrespective of
the length of the power failure. Alarms are acknowledged automatically and the drive is
restarted.
Prerequisites
The following general conditions must be satisfied in order that the drive can be switched on:
● The auxiliary supplies must not fail.
● The power supply for the fans, coolant pumps, and the open-loop/closed-loop controllers
must be maintained.
If the main infeed fails, the pulse block is initiated. The DC link is supported for a short time using
the precharge.
Operation
8.3 Functions
SINAMICS PERFECT HARMONY GH150 6SL3826
Operating Instructions 05/2020
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