optional back-up generator nuetral

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cwain

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I'm looking at an optional back up generator Transfer switch schematic and they are not switching the nuetral grounded conductor. So my question is when the generator is supplying power to the structure and lets say there is one 120 volt load carrying 10 amps. Will this be a safety issue for the power company with the nuetral having a 10 amp load? Could they be bit? And is this allowable by NEC.
 
I would venture to say that 95% of all generator installations across the country do not have the neutral switched in the transfer switch.

A sign at the proper locations is very important for the safety of all. See 702.8 for the requirements.
 
cwain said:
I'm looking at an optional back up generator Transfer switch schematic and they are not switching the nuetral grounded conductor. So my question is when the generator is supplying power to the structure and lets say there is one 120 volt load carrying 10 amps. Will this be a safety issue for the power company with the nuetral having a 10 amp load? Could they be bit? And is this allowable by NEC.
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If everything is properly done, it won't be an issue. In all cases the current wants to get back to its source--in this case the generator--so no current will flow to the utility. The neutral should still be bonded to ground at the service entrance and that will pull the neutral down to 0V.

Now, if you lost the neutral on your gen-set all bets are off...
 
the generator service drop is 2 hots 1 ground, the ground is bonded to the nuetral and grounding electrode conductor at the service entrance. According to Generator/Transfer switch schematic.
 
cwain said:
the generator service drop is 2 hots 1 ground, the ground is bonded to the nuetral and grounding electrode conductor at the service entrance. According to Generator/Transfer switch schematic.
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That is correct and the only place it should happen when you do not switch the neutral
 
Generator Nuetral

Generator Nuetral

I have a customer that has been backfeeding his house through his dryer outlet. Which is 220 volt with out a nuetral. They are using the ground to serve as the nuetral when they use the generator. The ground is bare. My questions is will this cause a problem using the bare ground to back feed the panel from the generator.
 
Whitetail said:
I have a customer that has been backfeeding his house through his dryer outlet. Which is 220 volt with out a nuetral. They are using the ground to serve as the nuetral when they use the generator. The ground is bare. My questions is will this cause a problem using the bare ground to back feed the panel from the generator.
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It 'is' a problem already, a generator must supply its power through a transfer switch. The

current set-up is not code compliant and worst than that, it is what the Linemen for the

POCO are hurt/killed by when the HO forgets to open the main breaker.
 
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