30 amp generator with 12 gauge wire?????
Ok, have a quick question for you electrical guys. I had to pull my Onan 4000 generator for some landing gear work. Noticed that the AC feed wires are 12 gauge and about 6' long before a junction box ...
Forum Discussion
enblethen wrote:
Something sounds funny!
It should be minimum 10 gauge wire for 30 amp. NEC requires 310 for 30 amp.
The AC unit should not be running directly off genset.
The genset should go through a transfer switch or on some rigs a receptacle where the shore power cord plugs in.
It then should go to a 120 volt power distribution panel. There a 20 amp breaker would feed the AC unit on #12 wire.
Onan only wire what is inside the genset. Connection to the rig is done by the rig's manufacturer. I would be checking with them!
I believe the wiring in question is part of an engineered system. Engineering calculations determined the wire size and temperature rating of the wire required.
As such the system does not have to comply with NEC requirements.
NEC covers systems that have not been engineered.
