Tt Line System - Siemens SINAMICS G120 Installation Manual

Connecting
4.1 Permissible line supplies
4.1.2

TT line system

In a TT line system, the transformer ground-
ing and the installation grounding are inde-
pendent of one another.
There are TT line supplies where the neutral
conductor N is either transferred – or not.
Note
Operation in IEC or UL systems
For installations in compliance with IEC, operation on TT line systems is permissible. For
installations in compliance with UL, operation on TT line systems is not permissible.
Converters connected to a TT system
● Converters with integrated line filter:
– Operation on TT line systems with grounded neutral point permissible.
– Operation on TT line systems without grounded neutral point not permissible.
● Converters with external line filter:
– Operation on TT line systems with grounded neutral point permissible.
– Operation on TT line systems without grounded neutral point not permissible.
● Converters without line filter:
– Operation on all TT line systems permissible.
48
Note
Special feature of FSG converters
FSG converters with integrated C3 line filter can be operated in TT line systems
without a grounded neutral point if you remove the screw for functional grounding.
Figure 4-2 Remove screw for functional grounding (Page 46)
If you remove the screw for functional grounding, the EMC properties deteriorate and
the requirements of Class C3 are no longer met.
Hardware Installation Manual, 01/2020, A5E33294624B AL
Power Module PM240-2