Generator as a separately derived system

[Strathead]

No, it is not code compliant to disconnect. I can't imagine that you can't disconnect the bond between the neutral to the ground in the generator, though.

 

[wwhitney]

So, to avoid code violation, can the EGC between the Generator and the Disconnect be disconnected?

The NEC has very limited allowances for using other than a dedicated bonding/grounding conductor for ground fault clearing. There's the allowance to use the grounded service conductor on the supply side of a service disconnect, as well as an allowance for circuits originating at an outdoor transformer. I don't believe there is any allowance for a generator.

So no, you need to install an EGC/bonding jumper between the generator and the disconnect. Your solutions to avoiding multiple N-G bonds in the system are only to remove the N-G bond at the generator, or use an ATS that switches the neutral. That's it.

Cheers, Wayne

 

[Joethemechanic]

I can't imagine that you can't disconnect the bond between the neutral to the ground in the generator, though.

These portable units they sell at all the big box stores, is there a jumper or a screw to lift the neutral ground bond? The only times I've worked on them was for applications that needed a n-g bond so I never paid any attention

I'm willing to bet most of them are hooked up to building wiring with the N-G bond intact just due to ignorance

 

[jaggedben]

Okay going back to this....

... I understand using a neutral switching transfer switch definitely makes a neutral bonded generator a SDS. However, to avoid the double N-G bonds issues, I am being told by a company that I should use a non-neutral switching transfer switch with the neutral bonded generator but don't connect the ground to the transfer switch. It doesn't sound quite right so I am doing a sanity check.

The 'company' seems to be wrong. This describes two incompatible methods.

Either...

1: SDS setup:
Neutral is switched
N-G bonds at service *and* generator

OR

2: Non-SDS setup:
Neutral is not switched
N-G bond required at service, prohibited anywhere else (including generator)

If you have a generator with an N-G bond that cannot be removed, then 1 is the only option. If you have a transfer switch that doesn't switch the neutral, then 2 is the only option. You can't use these two pieces of equipment in the same system.

 

[analog8484]

@Strathead, @wwhitney, @jaggedben: thank you for the explanations and confirming my suspicion.

 

[roger]

I'm willing to bet most of them are hooked up to building wiring with the N-G bond intact just due to ignorance

And even though it's somewhat of a hazard there's not (AFAIK) many accidents or problems reported.