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

Infeed

Pre-charging and bypass contactor chassis

1.5 Pre-charging and bypass contactor chassis
Description
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 con-
tactor. 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. For sizes HI and JI, the bypass contactor
must be separately provided.
For Smart Line Modules, the pre-charging itself is part of the Smart Line Module;
however, the bypass contactor must be externally mounted and installed.
Additional information: see the Equipment Manual.
Procedure during power ON/OFF
Power ON:
S The pre-charging contactor is closed and the DC link is charged via the
pre-charging resistors.
S Once pre-charging is complete, the bypass contactor is closed and the
pre-charging contactor opened. The DC link is pre-charged and ready for
operation.
If pre-charging could not be completed, fault F06000 is output.
Power OFF:
S The pulses are inhibited and the bypass contactor is then opened.
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© Siemens AG 2006 All Rights Reserved
SINAMICS S120 Function Manual, 03/2006 Edition
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