Means of disconnect to a building being fed from two meters

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Jmb399

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We recently upgraded a service due to an ADU being built. It is a 5 gang service. We were required to add a house panel that serves the lighting and out lets that are for common purposes. The inspector said and it does state in the NEC that a buiding can only be fed by one source unless there is one means of disconnecting on that building for all power. Any ideas on how this gets accomplished? I have one meter feeding the house panel and one feeding the adu's electrical needs?
 
Perhaps some clarification about the setup is an order also. So this is one building with a five gang meter center on it? Or are there multiple buildings? Not clear what the five meters are serving. Please provide details on the locations of all buildings and all service disconnects for meaningful answers.
 
The inspector is hand-waving a bit here- for one, there are circumstances where one structure might have multiple services. Or what looks like one building might count as multiple structures for the code. Anyway, look at the beginning of 230 and at 230.71 "The service disconnecting means for each service permitted [...] shall consist of not more than six switches or sets of circuit breakers [...] grouped in any one location."

Your power utility might also want a single meter disconnect, but that's a different beast.
 
electrofelon said:
Perhaps some clarification about the setup is an order also. So this is one building with a five gang meter center on it? Or are there multiple buildings? Not clear what the five meters are serving. Please provide details on the locations of all buildings and all service disconnects for meaningful answers.
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Two structures The first structure has 3 apartments and this is where the utility drop comes into the 5 gang distribution with the meters. The second structure which was a really big garage they converted half into an ADU. That structure is being fed by two meters one for the house panel and one for the ADU's electrical loads.
 
230.2 (A) - (D) deals with additional services, but from the sound you only have one service, then feeders from the meter stack to each unit/garage. (Are they wired as feeders with separate neutral and EGC?) The service on one building can supply power to another.

Assuming there is a proper firewall between the ADU and the garage space, this doesn't sound any different from a strip shopping center where each space is considered a separate structure and has it's own meter and disconnect. That said, you may need a pair of disconnects outside the ADU/garage where the feeders enter.
 
Jmb399 said:
Two structures The first structure has 3 apartments and this is where the utility drop comes into the 5 gang distribution with the meters. The second structure which was a really big garage they converted half into an ADU. That structure is being fed by two meters one for the house panel and one for the ADU's electrical loads.
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As Zbang said, we need to know if these are feeders or service conductors run to the second building. Also would need to know what code cycle you are under. Assuming these are feeders, under 2017 its a bit dicey and you could possible use 225.30(B)(1) or 225.30(E). If under 2020, this would be allowed under 225.30(B), with separate but grouped disconnects.
 
Jmb399 said:
230.2 A-D
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That tells when more than one service is permitted, you still can have 1 to 6 disconnecting means per service that is allowed.

One disconnect for all is going to be very impractical in most cases. Would need many poles on the switch at very least to even be able to physically do it.
 
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