Pre-Charging And Bypass Contactor Chassis - Siemens SINAMICS S120 Function Manual

Infeed

1.5 Pre-charging and bypass contactor chassis

1.5 Pre-charging and bypass contactor chassis
Pre-charging is the procedure for charging the DC-link capacitors via resistors. Pre-charging
is normally carried out from the feeding supply network, although it can also be carried out
from a pre-charged DC link. The pre-charging input circuit limits the charging current of the
DC-link capacitors.
The pre-charging input circuit for Active and Smart Infeed in the chassis design comprises a
pre-charging contactor with pre-charging resistors and a bypass contactor. The Active Line
Module controls the pre-charging input circuit in the Active Interface Module via terminals.
The pre-charging input circuit in the Active Interface Module of module types FI and GI
contains the bypass contactor. The bypass contactor must be provided separately for frame
sizes HI and JI.
With the Smart Line Module, pre-charging is integrated in the Smart Line Module itself,
although the bypass contactor must be provided externally.
Further information: See SINAMICS S120 Chassis Power Units Manual
Procedure during power ON/OFF
Power ON:
● The pre-charging contactor is closed and the DC link is charged via the pre-charging
● Once pre-charging is complete, the bypass contactor is closed and the pre-charging
Power OFF:
● The pulses are inhibited and the bypass contactor is then opened.
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resistors.
contactor opened. The DC link is pre-charged and ready for operation. If pre-charging
could not be completed, fault F06000 is output.
Function Manual, (FH1), 01/2013, 6SL3097-4AB00-0BP3
Drive functions