New service at detached garage already served by branch circuit.

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roger

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Wayne, go back to Charlies rule and let it go, you're going to overamp on this. Odds are your opinion will not change an inspectors, I know it hasn't changed mine.

We'll see what happens with your PI.
 

Little Bill

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Apparently I am, and the consequences of certain interpretations to those other cases.

Which is silent on whether there are any controls in house for garage loads on that branch circuit. I'm not saying it's likely, it's just not ruled out by the OP, so the comment is directly relevant to the OP.

It's certainly part of a branch circuit, just probably not the entire branch circuit. It would still fall under 225.30, which is why 225.30(E) mentions it.

Cheers, Wayne
I think you are arguing just for the sake of arguing. I'm sticking to the OP's case, not some "what if" case. He has a branch circuit as he described.
 

wwhitney

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Wayne, go back to Charlies rule
That doesn't help us, because the entire difference of opinion hinges on the breadth of the word "supply" in the title or first sentence of 225.30. Charlie's Rule doesn't tell us definitions. "Supply" is not an Article 100 term.

So the reader has to determine the meaning of the word "supply" there based on common usage and context. I'm placing a lot more emphasis on context than you seem to be.

Cheers, Wayne
 

wwhitney

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I think you are arguing just for the sake of arguing.
Entirely possible. : - )

I'm just saying the OP's description doesn't rule out all the exceptions in 225.30. Of course it obviously doesn't rule any of them in. And this is a tangent anyway, since 225.30 is complied with when there is only one branch circuit or feeder supplying the building.

Cheers, Wayne
 
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hillbilly1

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I’ve seen it done before because they wanted to switch the garage lights from the house. With the advent of wireless switches, that can be gotten around now.
 

jaggedben

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But you just made up the "at the building" part. It's not in the text.

It's implied by the whole thing. 'Building or structure ... served by a feeder or branch circuit on the load side of the service disconnecting means". If the service disconect is at the building then the building isn't served 'on the load side...'.

It's clear what they mean even if they could have said it more clearly. I think if I put in a PI to change it to 'building or structure served by a feeder or branch circuit whose source of supply is through service equipment located at another building or structure', they would either accept it or else reject it on the basis that it already says that.

I did come up with another meaning for "on the load side of a service disconnecting means." So that limitation has the effect that you can have two different non-grid based supplies to a building if there are no grid-based supplies to the building.

Cheers, Wayne
Perhaps, but I think that's already covered by the other allowances in 225.30 and 230.2, such as parallel power production or different characteristics/uses. So that's not the meaning.
 

wwhitney

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It's implied by the whole thing. 'Building or structure ... served by a feeder or branch circuit on the load side of the service disconnecting means". If the service disconect is at the building then the building isn't served 'on the load side...'.
Doesn't "served by" already mean that the conductors have one end (sufficiently) far from the building, and the conductors power loads located in or on the building? I'm thinking they are just being redundant to emphasize something.

I think if I put in a PI to change it to 'building or structure served by a feeder or branch circuit whose source of supply is through service equipment located at another building or structure', they would either accept it or else reject it on the basis that it already says that.
OK, let's say your PI has been accepted. I don't see how that changes anything discussed in this thread. Maybe I'm missing your point.

Cheers, Wayne
 
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wwhitney

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The meaning is: Where a feeder or branch circuit supplies a building from service equipment that is not at the building, then no other feeders or branch circuits shall supply the building whether or not their service disconnect is at the building. (That is, unless the other specific allowances apply.)
If the above is your point, and that the above would prohibit the arrangement in the OP, then:

Say a service disconnect is on outside of the building, and it supplies feeders or branch circuits that run only on or in the building to supply loads only on or in the building. Then with respect to those conductors, the building is supplied only by the one service. The feeders or branch circuits are not supplying "the building". [Suppose they were, and replace the service with a feeder from another building. Now 225.30 prohibits those additional feeders on or in the building, which is nonsense.]

I.e. for a building without internal power sources, "supply the building" means "carry power from a location (sufficiently far) outside the building to a load on or inside the building".

Cheers, Wayne
 
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jaggedben

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Doesn't "served by" already mean that the conductors have one end (sufficiently) far from the building, and the conductors power loads located in or on the building?
Good question. Also does 'served by' mean something different from 'supply'/'supplied by? If so, why once again, did they switch from 'served by' to 'supply' in the first sentence of 225.30? If 'served by' means what you suggest, but 'supplied' could mean any part or all of the conductors within the building or structure. In that case, for our OP, the existing branch circuit 'serves' the garage but the new branch circuits 'supply' it in violation.

I'm thinking they are just being redundant to emphasize something.


OK, let's say your PI has been accepted. I don't see how that changes anything discussed in this thread. Maybe I'm missing your point.
My point is simply that the the first sentence way 225.30 is written, the 'only one' circuit must be the feeder or branch circuit that 'serves' the building. Otherwise the building is 'supplied' by more than one feeder or branch circuit.

Also, I still say there's a 230.2 violation. Note 230.2 only uses 'supply' not 'served.' The branch circuit is supplied by one service. The new service is a second one.
 

wwhitney

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Also does 'served by' mean something different from 'supply'/'supplied by?
My reading so far has been that they mean the same thing. I'll ponder your points to see if I can divine an intended distinction. : - )

See my post just previous for my thinking on what "supply the building" means.

Also, I still say there's a 230.2 violation.
Basically everything I've said about 225.30 applies to 230.2 as well:

"Supplied by only one X" means you can't have two or more X. It doesn't restrict other forms of supply. That restriction would need to be written as "supplied only by one X" or "only supplied by one X".

And the scope in 230.1 limits it to services, not other forms of supply.

Cheers, Wayne
 

jaggedben

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To me supply means direct or indirect. A building supplied by a branch circuit is also supplied by the feeder which supplies the branch circuit and the service which supplies the feeder. So the branch circuit in the OP still constitutes supply by another service and violates 230.2.

In any case, clearly the intent of both 225.30 and 230.2 is to generally prohibit multiple supplies of electricity being installed willy nilly to a building or structure without a good reason. That makes a lot of general sense from both emergency response and a worker safety reasons. If for whatever reason power needs to be completely shut down to a building or structure it should not be unduly complicated to figure out how to do that. The code identifies a number of valid reasons to have more than one separate supply, but simply because one is a feeder or branch circuit and the other is a service is not one of those reasons.

So, even if you could get us to agree you've identified a loophole, that loophole ought to be closed, not codified, by any code changes.
 

wwhitney

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To me supply means direct or indirect. A building supplied by a branch circuit is also supplied by the feeder which supplies the branch circuit and the service which supplies the feeder.
That yields a logical paradox--we can never supply a building with a branch circuit, because then it is also supplied by the feeder that supplies the branch circuit, and we've violated 225.30.

So that notion doesn't work. The supply is only by the (upstream-most) conductor that crosses the boundary between "not building" and "building."

clearly the intent of both 225.30 and 230.2 is to generally prohibit multiple supplies of electricity being installed willy nilly to a building or structure without a good reason. . . . loophole . . .
If you feel that is the intent, and there is or may be a loophole, why don't you submit a PI to change the first sentence of 225.30 to

"A building or other structure supplied by a service, feeder, or branch circuit shall not be supplied by a different feeder or branch circuit unless permitted in 225.30(A) through (F)."

And another to change the first sentence of 230.2 to

"A building or other structure supplied by a service, feeder, or branch circuit shall not be supplied by a different service unless permitted in 230.2(A) through (D)."

I'd happily submit the PI, but any substantiation I would write would be half-hearted at best.

Cheers, Wayne
 

Greentagger

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Thank all of y’all for the nice debate. Lots of knowledge on this site.
 

hornetd

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Maryland
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IMO the wording of 225 would prohibit the addition of a service.

225.30 Number of Supplies. A building or other structure
that is served by a branch circuit or feeder on the load side
of a service disconnecting means shall be supplied by only
one feeder or branch circuit.

Barring the specific allowances the words "Shall be supplied by only one feeder or branch circuit" means exactly that.

So if the building was already supplied by a branch circuit that is all that is allowed to supply it.
I kept the original 3 way switch arrangement of 4 wires in conduit to a detached garage and ran a feeder to it for it's new use as a shop. Inspector didn't like it but when I pointed out that it had 1 interior light and one receptacle plus the switched outside lights and that was to provide emergency power to the building he gave me his that is a reach look but he handed me his signed green sticker.

Tom Horne
 

hornetd

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Doesn't "served by" already mean that the conductors have one end (sufficiently) far from the building, and the conductors power loads located in or on the building? I'm thinking they are just being redundant to emphasize something.
Dam I hope not. I used buildings to support a lot of stuff that had nothing to do with the building except that is were the load was mounted. Mostly that was for exterior lighting. If your use of "or on" is correct every outdoor light would have to be supplied from the building it is mounted on. One great example is wanting an exterior light so you can find your way to the garage safely. If I ran the 3 way switching circuit back from the garage end to make it possible to have control from the house were the service is located would someone see that as having 2 supplies to the house. I'm not saying that would be a legitimate application of 225.30 but this is getting very convoluted the way some people are looking at it.

Tom Horne
 
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