5.1.2
TT line system
In a TT line system, the transformer grounding
and the installation grounding are independ‐
ent of one another.
There are TT line supplies where the neutral
conductor N is either transferred – or not.
7UDQVIRUPHURU
JHQHUDWRU
7RWKHV\VWHP
([DPSOH 7UDQVIHURI1JURXQGHGQHXWUDO
SRLQW
/
/
/
1
3(
Inverter operated on a TT line system
● Inverter with integrated or external line filter:
– Operation on TT line systems with grounded neutral point permissible.
– Operation on TT line systems without grounded neutral point not permissible.
● Inverter without line filter:
– Operation on all TT line systems permissible.
● For installations in compliance with IEC, operation on a TT line system is permissible. For
installations in compliance with UL, operation on a TT line system is not permissible.
Connecting-up
5.1 Permissible line supplies
Power Module PM240-2
Hardware Installation Manual, 08/2017, A5E33294624B AG
51