Delta VFD-ED Series

Appendix A. EMC Standard Installation GuideVFD-ED
A-11
TN system
TN: The neutral point of the low voltage transformer or generator is earthed, usually the star point in a
three-phase system. The body of the electrical device is connected to earth via this earth connection
at the transformer.
Protective earth (PE): The conductor that connects the exposed metallic parts of the consumer.
Neutral (N): The conductor that connects to the start point in a three-phase system or that carries the
return current in a single-phase system.
L1
L2
L3
N
PE
TN-S system
TN-S: PE and N are two separate conductors that are combined together only near the power source
(transformer or generator). It is the same as a three-phase five-wire system.
Figure A-9
Figure A-10