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Old 12-03-2018, 01:42 PM   #42
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Originally Posted by panjumbie View Post

Additionally, if you check the listing restrictions on small portable generators, the article below says that the listing of the generator requires any transfer switch used with the generator to switch the neutral as well as the "hot" conductors. Circuit breaker interlocks can't do that. The NEC section on ground bonding limits most electrical systems to a single bond between the neutral and the safety ground, typically at or near the service disconnect. I think you'll find small portable generators have the neutral tied to the ground connections on the outlets (so that a ground fault can trip the breaker or GCFI) and probably also the frame of the generator. The NEC requires the portable generator ground to be tied to the building ground, and without a transfer switch that switches the neutral you will have a second bond between the neutral and the safety ground, which can cause stray currents in your system. If your portable generator has GCFI's, these stray currents may possibly cause tripping of the GCFI's. Since I don't have copies of the listing requirements (I do have a current copy of the NEC), I can't comment on the listing issues beyond what I've mentioned here.

Regarding people being injured or killed by backfeeds, Google "Lineman injuries from backfeeds". There are hundreds, maybe thousands, of links.
This is my generator setup and have been using it for 15 years..does it look OK?

7000 EXL Generac generator..neutral and ground are bonded.
Protran 6 circuit transfer switch which does not switch bonded neutral to floating neutral before going into circuit panel.
Seimens 200amp panel with neutral bonded to ground.

Would this pass inspection by the code cop?
It's never crowded along the extra mile.
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