NGR Connection Through ATS

The first thing you need to do is contact an electrical engineer who knows the codes and standards where your project is located.

If this was in Canada, I would tell you that.... with a 3 pole transfer switch, the neutral from the transformer and the neutral from the generator must be connected to a hard bolted neutral bar in the transfer switch and that any neutral to case ground at the generator needs to be removed.

As to where the HGR resistor gets connected depends upon where your utility service point is located.

If the secondary of your transformer is your service box, then the HGR resistor must be connected between the neutral of the transformer and the system grounding grid with nothing between them. As well, a connection between the neutral from the transformer must be bonded to your equipment bonding system.

If the transformer is not your service point from the utility system, the HGR needs to be connected to the utility service point neutral and the bonding system needs to be established. These two separately derived systems need to be interconnected from a grounding perspective.

Call a pro...

Interesting, your local utility allows customers to tamper with the utility mandated earthing methods, and utilizes High Resistance Grounding on its distribution transformers? Both are highly unlikely in systems where codes are followed.

It is much easier, safer, and cheaper to simply install a dedicated NGR in the generator neutral. Problem solved, and your AHJ (like North of 60), will be much happier.

Get a copy of the latest revision of IEEE Std C62.92.4-2014 for more info.