New service at detached garage already served by branch circuit.

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wwhitney

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P.S. I just submitted a PI to change the title of 225.30 to "Number of Branch Circuit or Feeder Supplies" to avoid this misinterpretation. So we'll have an answer from the CMP in a couple years.
 

roger

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P.S. I just submitted a PI to change the title of 225.30 to "Number of Branch Circuit or Feeder Supplies" to avoid this misinterpretation. So we'll have an answer from the CMP in a couple years.
And in the mean time I can see an inspector denying it and rightfully so.

All this nonsense aside, I'm sure it wouldn't be to difficult to cut a branch circuit and refeed it from the new service?
 

wwhitney

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This was my thought as well!
Sure for a typical branch circuit. But there are certainly cases where it's not that simple. E.g. if there's some power line communications controls that let you turn the garage lights on or off from the main house.

In which case, 225.30(E) would allow, say, one feeder and one branch circuit. But under the misreading of 225.30 proposed, it wouldn't allow one service and one branch circuit.

Cheers, Wayne
 

jaggedben

Senior Member
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Solar and Energy Storage Installer
...

Again, your interpretation yields the unreasonable result that a building might be allowed to have two feeders for one of the allowed reasons (225.30), or two services for that same reason (230.2), but one service and one feeder would be prohibited.

I'm not following you here.
Note the phrase 'on the load side of the service disconnecting means' in the second adjective clause of the first sentence in 225.30. And note how that phrase is not repeated when 'feeder or branch circuit' is repeated later in the sentence.

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.)

As far as 225.30 vs. 230.2, only 225.30(A)(8) is at stake. (Docks and piers). Because you're not going to find EV equipment listed for more than one service, and the list of special conditions is otherwise the same. I don't see any unreasonable result.

Per the scope and the structure of 225, it can not and does not regulate services. While the title of 225.30 is "number of supplies" without immediate qualification, the title of Part II just above that is "Buildings or Other Structures Supplied by a Feeder(s) or Branch Circuit(s)." That qualifies the meaning of the word "supply" in 225.30 only to supply by a feeder or branch circuit.
The existing branch circuit puts the OP's garage under the scope by any part of what you quoted. The new service violates the section in its own words. One doesn't even have to look at 230.2 to conclude this, although looking there also finds a violation.
 

Sea Nile

Senior Member
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Georgia
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I agree that the set up was in compliance before the service was added.

However, the violation was created when they added the service to the garage.

They should have deleted the branch circuit from the residence, like many others have stated, before connecting the new service. Then tie in the existing lights and receptacles to the new service.

I would also strongly consider connecting the two grounding electrode systems together via an underground solid bare copper wire minimum AWG 6.
 

wwhitney

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Note the phrase 'on the load side of the service disconnecting means' in the second adjective clause of the first sentence in 225.30. And note how that phrase is not repeated when 'feeder or branch circuit' is repeated later in the sentence.
I'm not sure why you are focusing on that language. From my point of view, any branch circuit or feeder is on the load side of a service disconnecting means, so the phrase you quoted is 100% redundant and could be deleted without any change in meaning.
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.)
Sure. But that's silent on whether a different service could also supply the building.

Or are you reading "supply" to mean "provide power to anything inside the building," rather than "convey power from outside the building to inside the building"? I think the latter is generally understood to be the meaning at hand, since Article 225 is "Outside Branch Circuit and Feeders." So branch circuit and feeders internal to the building and outside of the scope of Article 225.

The existing branch circuit puts the OP's garage under the scope by any part of what you quoted. The new service violates the section in its own words.
No, because services are not subject to Article 225, and the word "supply" in 225.30 always means "branch circuit or feeder supply," per the title of Part II, the scope in 225.1, and the tile of the Article.

Cheers, Wayne
 

wwhitney

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I'm not following you here.
Suppose for the sake of argument the word "supply" in the title of 225.30 is meant to cover services. And say you have a building with a fire pump, just to pick the first item in 225.30(A).

Then 225.30(A) would allow the building to be supplied by two feeders, one for the fire pump and one for everything else. And 230.2(A) would allow the building to be supplied by two services, one for the fire pump and one for everything else.

But apparently disallowed is supplying the building with a service for the fire pump, and a feeder for everything else. Because 225.30(A)(1) only allows an "additional branch circuit or feeder" as the supply for the fire pump, not a service.

That makes zero sense. And it just demonstrates again that the word "supply" in the title of 225.30 does not cover services.

Cheers, Wayne
 

wwhitney

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Location
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I'm not sure why you are focusing on that language. From my point of view, any branch circuit or feeder is on the load side of a service disconnecting means, so the phrase you quoted is 100% redundant and could be deleted without any change in meaning.
I take back that last sentence. Only a branch circuit or feeder supplied by a service is on the load side of a service disconnecting means. You could have a stand-alone system, supplied by a generator or ESS powered microgrid or whatever, and that would give you a branch circuit or feeder that's not on the load side of a service disconnecting means.

Cheers, Wayne
 

jaggedben

Senior Member
Location
Northern California
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Solar and Energy Storage Installer
I'm not sure why you are focusing on that language. From my point of view, any branch circuit or feeder is on the load side of a service disconnecting means, so the phrase you quoted is 100% redundant and could be deleted without any change in meaning.
Right, it sounds redundant, so I asked myself why they put it there. It's to clarify that the section doesn't apply to feeders and branch circuits whose service disconnect is at the building. A service at the building can supply any number of feeders and branch circuits at that building, and that's not within the scope. But if the service disconnect is elsewhere. 225.30 applies. Read again what I said anout the lack of repetition.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
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One could argue that this applies to every service with a disconnect:

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.
 

Little Bill

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Sure for a typical branch circuit. But there are certainly cases where it's not that simple. E.g. if there's some power line communications controls that let you turn the garage lights on or off from the main house.

In which case, 225.30(E) would allow, say, one feeder and one branch circuit. But under the misreading of 225.30 proposed, it wouldn't allow one service and one branch circuit.

Cheers, Wayne
We are not talking about other cases. The OP said the BC was for general use lights, receptacles, etc. So I see no reason a new BC couldn't be pulled from the new service. Also, IMO, a set of conductors ran for a 3-way switch is not a BC, nor is a remote controlled switch.
 

wwhitney

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Location
Berkeley, CA
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Retired
Wayne, replace 'new service' above with 'new branch circuits supplying the EVSEs' and then reread my argument about 225.30.
If the new service is on a pole away from the garage, and the EVSE(s) are inside the garage, then I agree that's a 225.30 violation.

Otherwise, the building in the OP is served by a service and a branch circuit, and 225.30 does not prohibit that configuration.

Cheers, Wayne
 
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roger

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Desperation calls for grasping at straws no matter how far out there they may be. 😁
 

wwhitney

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Location
Berkeley, CA
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Right, it sounds redundant, so I asked myself why they put it there. It's to clarify that the section doesn't apply to feeders and branch circuits whose service disconnect is at the building.
But you just made up the "at the building" part. It's not in the text.

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
 

wwhitney

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Location
Berkeley, CA
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Retired
We are not talking about other cases.
Apparently I am, and the consequences of certain interpretations to those other cases.
The OP said the BC was for general use lights, receptacles, etc.
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.
Also, IMO, a set of conductors ran for a 3-way switch is not a BC, nor is a remote controlled switch.
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
 

wwhitney

Senior Member
Location
Berkeley, CA
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Let me summarize the state of (2020) Article 225 and 225.30 with respect to this question:

1) Other than the heading of 225.30, every use of the notion of a "supply" to a building in 225.30 explicitly refers to "branch circuits or feeders".
2) The heading of Part II refers to "branch circuits or feeders".
3) The scope of the article in 225.1 is listed as "branch circuits or feeders."

So now we have two competing interpretations:

A) The omission of the qualifier "branch circuit or feeder" in the heading of 225.30 is intentional, so that the rest of that section does cover services.
B) The omission is either unintentional or for purposes of brevity and has no significance.

I strongly favor (B), because of items (1) through (3). (A) leads only to other inconsistencies that I've pointed out previously. My original point about the placement of the word "only" also slightly favors (B) as well.

Cheers, Wayne
 
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