Operating Instructions
4.4.1.2 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.
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7RWKHV\VWHP
([DPSOH 7UDQVIHURI1JURXQGHGQHXWUDO
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/
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1
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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.
Inverter connected to a TT system
● Inverters 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.
Note
Special feature of FSG inverters
FSG inverters 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.
Permissible line supplies (Page 86)
If you remove the screw for functional grounding, the EMC properties deteriorate and
the requirements of Class C3 are no longer met.
● Inverters 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.
● Inverter without line filter:
– Operation on all TT line systems permissible.
Installing
4.4 Connecting the line supply and motor
Converter with the CU230P-2 Control Units
Operating Instructions, 04/2018, FW V4.7 SP10, A5E34257946B AF 89