Location of Neutral Ground Connection

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natfuelbill

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250.24(A)(1) requires the Grounding Electrode Conductor be connected to the Grounded Service Conductor to be connected at load side of service drop, or meter enclosure or in service disconnecting means.

For a situation with a system with a full-capacity backup generator. The generator is not a separately derived system and the ATS is 3-pole.

1) Can this NG connection be located in a downstream ATS (automatic transfer switch) immediately after the service disconnecting means?
2) If yes, what NEC section allows this location?
 
natfuelbill said:
250.24(A)(1) requires the Grounding Electrode Conductor be connected to the Grounded Service Conductor to be connected at load side of service drop, or meter enclosure or in service disconnecting means.

For a situation with a system with a full-capacity backup generator. The generator is not a separately derived system and the ATS is 3-pole.

1) Can this NG connection be located in a downstream ATS (automatic transfer switch) immediately after the service disconnecting means?
2) If yes, what NEC section allows this location?
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No, not that I'm aware of. If the ATS is immediately after, does that mean adjacent to the SDM? If so, why is bonding at SDM an issue?
 
The bonding is at the ATS. The ATS and MSD enclosures are next to each other. If is a code violation I want fix it.

Would this installation meet the intent of dual-fed as in 250.24(A)(3)?
 
Most interesting question.
In 250.30(A)(1) you have similar wording for dual fed SDS systems.
It appears, if you met all the criteria, you could do so on dual fed services and dual fed SDS, but your situation does not technically comply as you have only one "service" based on NEC definition and you have no SDS.
Al hough I see no harm (not that that matters), in your situation I think such a connection would violate 250.24(A)(5)
At the same time, it seems the N-G connection in the service disconnect would
accomplish the same thing without being a possible violation. (so why ?)
 
If the ATS has a service rated disconnect in it (most I have installed lately do) then eliminate the other disconnect and make this ATS your service disconnect and do your bonding there.

when I have an existing service disconnect many times I have put the new ATS in its place, or I gut the old disco and use it as an R-3 junction box re-routing the service conductors to the new ATS, but if the ATS doesn't have the breaker/service disconnect in it, then the existing disconnect stays and is the bonding point.
 
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