Siemens sinamics G120 Operating Instructions Manual page 74

Installing
4.5 Connecting the line supply, motor, and inverter components
IT system
In an IT line system, all of the conductors are insulated with respect to the PE protective
conductor – or connected to the PE protective conductor through an impedance.
There are IT systems with and without transfer of the neutral conductor N.
Inverter operated on an IT line system
● Inverters with integrated line filter:
– Operation on IT line systems not permissible.
● Inverter without line filter:
– Operation on all IT line systems permissible.
Example for inverters connected to an IT line system
Image 4-4
Behavior of the inverter when a ground fault occurs
In some instances, even for a ground fault, the inverter should still remain functional. In
cases such as these, you must install an output reactor. This prevents an overcurrent trip or
damage to the drive.
74
IT line supply where the neutral conductor N is transferred and with impedance with
respect to the PE protective conductor
Operating Instructions, 01/2016, FW V4.7 SP6, A5E31759476B AE
Converter with CU250S-2 Control Unit