Siemens SINAMICS S120 Combi - Operating Line Connection Components Via an Isolating Transformer

Line-side power components
2.8 Line connection versions
SINAMICS S120 Combi
54 Manual, Edition 07/2012, 6SL3097-4AV00-0BP3
2.8.3.5 Operating line connection components via an isolating transformer
An isolating transformer converts the line supply type of the plant or system (e.g. IT/TT line
supply) to a TN line supply. Additional voltage adaptation to the permissible voltage
tolerance range is possible.
An isolating transformer must be used in the following cases:
● The insulation of the Motor Module and/or the motor is not suitable for the voltages that
occur.
● There is no compatibility with an existing residual-current protective device.
● The installation altitude is higher than 2000 m above sea level.
● A line filter should be used in a line supply system that is not a TN line supply system with
grounded neutral conductor.
CAUTION
If the line supply voltage is greater than 480 V +10 %, it is not permissible to use an
autotransformer.
An isolating transformer must be used to ensure protective separation.
An isolating transformer must have the following properties:
● The transformer secondary must be in the star connection (a delta connection is not
permissible!)
● The neutral conductor must be brought out. It must be connected with the PE of the line
filter, line reactor and S120 Combi (infeed).
Notice: If the neutral conductor is not brought out and/or not connected, then all of the
restrictions of an IT line supply apply!
● If the line supply is available in a star connection on the primary side, then the vector
group that is required is: Yyn0
● If the line supply is available in a delta connection on the primary side, then the vector
group that is required is: Dyn5