A 4-gang meter pack with (4) 200-amp CBs feeds a 4 unit strip store. 2 of the units are wired. I am doing the other 2. The meter stack is located on the rear of first unit and underground conduits feed the 3rd and 4th units which are about 75 and 125 feet away.
The drawing shows a main lug panelboard, and the AHJ says this is OK, but I was wondering if the units should have a main disconnecting means.
Steve: I don't get your point. There are 4 mains, with 4 meters, feeding four (4) spaces. That provides a disco for each of the 4 panels, within the 4 spaces.
This is a common set-up in strip malls, providing they conform to six (6) switches or less. Redsy was concerned with a 'main' in the tenant panel, so only one movement of the hand would shut down the space.
There is a requirement that breakers be accessible to the tenant; NEC citations aside, this is often a requirement modified by local ordinance, and may be addressed by other codes as well.
Depending on the exact configuration .... for example, whether the meters, etc., are accessible, or locked up in an electrical room .... a main breaker in the tenants' panel, as well as a main disconnect before the meters may make sense.
Having a main disconnect has other advantages, even if we are still well under the '6 throws' maximum. Again, depending on the exact jobsite, putting a main in now will save a lot of trouble later, if the place ever grows / is divided past the '6 throws' rule.
Here is one result of such growth:
#179088 - 06/25/0805:28 PMRe: Service disconnect v. building disconnect
Reno: Yes, you think as I do with my EC hat on, a main is a great thing, future planning is a great thing! With my AHJ hat....it has to be NEC compliant ('05 in NJ, amended by the UCC).
Yes, I've seen splits, modifications, added tenants, divided and sub-divided ppaces, and a lot of nightmares as an EC. Yes, I came upon a 7 meter, no main...and I lost count of the # of throws last week. a multi occupant office bldg, modified and butchered many times over.
BTW, I may have been incorrect, but 'most' meter stacks are outside on strip stores; perish the thought of using space for an electric room when you get $$$ per sq ft.
Hotline, I really try to dodge "what is the code minimum" type of question .... if for no other reason that Article 90 tells us not to use the NEC as a design manual. Naturally, when I point this out, someone will reply "but Article 90 is not an enforceable part of the NEC."
Another reason is that there are very few times a 'one rule fits all' practice actually does fit all! Add to that the continuing influence of other codes (ICC, UFC, etc.) and a simple NEC answer might be incorrect. For example, the Fire Department might want a shunt trip for the entire building, regardless of how many meters there are.
I too tell many people, both EC's and HO's that the NEC is not a design tool. And explanations that some items within the NEC are 'minimums' and some are 'maximums'. And yes, many EC's are not aware of all the other 'codes', but we try to pass on the info at CEU classes, and thru one-on-one conversations.
My point to Redsy was and is what he asked is not a NEC requirement as he explained it. My comment that he could install the main, was and is still MHO. Many EC's call and look for opinions, but in the eyes of the state, I cannot provide 'official opinions', only NEC/UCC reference.