Operating Instructions
4.4.1.3 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 connected to an IT line system - FSA … FSF
● Inverters with integrated line filter:
– Operation on IT line systems not permissible.
● Inverter without line filter:
– Operation on all IT line systems permissible.
Note
690 V inverters: Output reactors for frame sizes FSD and FSE
An output reactor is required for 690 V inverters in frame sizes FSD and FSE.
Inverter with PM330 Power Module operated on an IT line system
When connected to an IT line supply, you must open the connection to the basic interference
suppression board of the Power Module.
Further information is provided on the Internet:
Hardware installation manual for PM330 Power Modules (https://
support.industry.siemens.com/cs/ww/en/view/109742506)
Inverter with PM240-2 FSG Power Module operated on an IT line system
The inverters have an integrated C3 line filter. Operation on IT line systems is only permissible
if you remove the grounding screw at the inverter.
Permissible line supplies (Page 86)
Behavior of the inverter when a ground fault occurs
You must install an output reactor if the inverter is to remain operational even when a ground
fault occurs at the inverter output. This output reactor prevents an overcurrent trip or damage
to the inverter.
Installing
4.4 Connecting the line supply and motor
Converter with the CU230P-2 Control Units
90 Operating Instructions, 04/2018, FW V4.7 SP10, A5E34257946B AF