2029 PI: 215.18(A)

[wwhitney]

Change:

215.18 (A) Surge-Protective Device.
If feeders supply any portion of the following, surge-protective devices (SPDs) shall be installed:

. . .

Substantiation:

There is some uncertainty as to the number of SPDs required in scenarios such as the following for a dwelling unit:

Feeder supplying all the loads --> Panelboard A with some branch circuits --> Feeder within the dwelling unit --> Paelboard B with other branch circuits.

Are SPDs only required in Panelboard A, or in both Panelboards A and B? If "supply" means "bring power into the location from elsewhere", then the present language only requires SPDs in Panelboard A. Whereas if "supply" means "supply any portion of", then SPDs are required in both Panelboards A and B.

Given the wording of 215.18(B), and in particular the informational note, my understanding is that the intention is to have SPDs in both panelboards. In which case this PI will improve clarity by making that unambiguous.

If I'm mistaken, then an alternative adjustment to the wording that makes it clear that SPDs are only required in Panelboard A would improve clarity.

 

[don_resqcapt19]

I think the rule should be in the panelboard article. SPDs shall be installed in or at any panelboard that supplies branch circuits for the following occupancies.

 

[wwhitney]

I think the rule should be in the panelboard article. SPDs shall be installed in or at any panelboard that supplies branch circuits for the following occupancies.

Or in Article 210, as branch circuits could be supplied from something other than a panelboard.

But unless 210, 215, and 230 are all under the same CMP, doing that would require coordination between the CMPs. My luck with PIs has been poor enough I'm not going to tackle that.

Cheers, Wayne

 

[don_resqcapt19]

Or in Article 210, as branch circuits could be supplied from something other than a panelboard.

But unless 210, 215, and 230 are all under the same CMP, doing that would require coordination between the CMPs. My luck with PIs has been poor enough I'm not going to tackle that.

Cheers, Wayne

210 is CMP2 and 215 and 230 are CMP 10