Neutral on a Supply Side Connection (not PV)


Puerto Rico
Electrical product applications
Hello everyone. I work for a manufacturer of a product that utilizes a simple single-pole circuit to measure for the presence of grid voltage on the SE cables of residential electrical systems. We use grid voltage as a proxy for the presence of grid power, which effects what our device does. We do not get too involved in how our installation partners wire up their systems, but most are using an IPC to connect to one leg on the supply side, using #6 run to a finger-safe fuse holder mounted in the ATS enclosure, then going to a smaller diameter wire for the home run to our relay that signals grid presence. This is usually installed in conjunction with PV and storage, but the supply side connection they are making for our product is simply for sensing the grid a la 230.82(4) [2017]. Most interpretations out there are about supply-side connections for PV, so I want to ask here in case there's anything unique about this different use case.

Question 1: As this is a direct connection on the supply side of the main disconnect, it seems like the ungrounded conductor requires a service-rated disconnecting means in an accessible location (not inside the ATS enclosure). Am I right about that?

Question 2: Should the ungrounded conductor be connected to the enclosure and the GEC inside the ATS? I have a feeling a lot of installers are running it back to the neutral bar on the main distribution panel.

Ultimately, most installers will do what they need to do to sleep well at night and keep the inspector happy. Because there are so many code cycles and local interpretations, we don't get too prescriptive about this part of the installation, and we almost never have a customer ask us how to do it. Nevertheless, I'd love to know the consensus so that we can pass along good information and hope that it's utilized.