4.8.1.3
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.
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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.
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.
4.8.2
Protective conductor
WARNING
Electric shock due to interrupted protective conductor
The drive components conduct a high leakage current via the protective conductor. Touching
conductive parts when the protective conductor is interrupted can result in death or serious
injury.
● Dimension the protective conductor as stipulated in the appropriate regulations.
Installing
4.8 Connect the line supply, motor and braking resistor
SINAMICS G120C converter
Operating Instructions, 09/2017, FW V4.7 SP9, A5E34263257B AF
67
