Service disconnect location 230.70(A)(1)

tortuga

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
230.70(A)(1) states :
Readily Accessible Location. The service disconnecting
means shall be installed at a readily accessible location either
outside of a building or structure or inside nearest the point of
entrance of the service conductors.
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Do you read this as
A) Service conductors can enter a structure then exit again ?
or
B) If conductors are not considered 'outside the structure' as defined in 230.6 they need to hit a service disconnect nearest the point of entrance ?

Say you have an existing service point that is inside the structure in a utility meter (CT can in an electrical room or flush mount meter in a garage wall etc), then service conductors travel across (non 230.6 space) aka the 'interior' of the building then exits again (230.6 space) into a service disconnect.
Since the service disconnect is outside is it not required to be nearest the point of entrance?
In this case there could be a unlimited length of unfused conductors inside the building.
Thanks for your thoughts
 
tortuga said:
...

Say you have an existing service point that is inside the structure in a utility meter (CT can in an electrical room or flush mount meter in a garage wall etc), then service conductors travel across (non 230.6 space) aka the 'interior' of the building then exits again (230.6 space) into a service disconnect.
Since the service disconnect is outside is it not required to be nearest the point of entrance?
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It is interesting that the code seems to assume service points cannot be inside buildings, but I would argue in such a case that the service conductors still 'enter' at the service point.

In this case there could be a unlimited length of unfused conductors inside the building.
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Which, however it's worded, the section quoted clearly intends to prohibit.
 
jaggedben said:
Which, however it's worded, the section quoted clearly intends to prohibit.
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True, and for good reason, but the OP has pointed out a loophole in the wording of 230.70(A)(1). It should instead read:

"The service disconnecting means shall be installed at a readily accessible location. If service conductors enter a building or structure, the service disconnecting means shall be located inside nearest the point of entrance."

Cheers, Wayne
 
jaggedben said:
Well, that wouldn't be sufficient because in the case where the service point is inside the building the intent would be something like 'nearest the service point'.
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On the theory that if the service conductor originate inside the building, they never "enter" it? I would see them as "entering" at the service point, but if you don't like that, we could wordsmith around that. E.g.

"If service conductors enter or originate inside a building or structure, the service disconnecting means shall be located inside nearest the point of entrance or origination."

Cheers, Wayne
 
Interesting thanks for the feedback, I have always gone with 'B' and I am sure inspectors in my area do also, I am also sure its an AJH call.

While traveling over the holidays I saw a fresh solar install on a two family dwelling (house with an apartment over attached garage) where outside there is a older dual meter pack with no main breakers, just two meters, then there are two service entrances to the basement
In the basement there is a 100A main for the apartment and a 150A main breaker loadcenter for the house.
The solar installer tapped the line (source) side of the 150A service entrance conductors in the basement loadcenter and then ran back out of the basement and set a disconnect next to the meter pack (probably to meet a utility requirement).
So evidently some people interpret that as 'A' which got me thinking.
 
tortuga said:
So evidently some people interpret that as 'A' which got me thinking.
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Not necessarily if this was done under a code earlier than the 2023 NEC. Wasn't the status of the line-side interconnection conductors as service conductors somewhat ambiguous in earlier code sections, with 690 or 705 even having some special allowances for them?

Cheers, Wayne
 
tortuga said:
...
The solar installer tapped the line (source) side of the 150A service entrance conductors in the basement loadcenter and then ran back out of the basement and set a disconnect next to the meter pack (probably to meet a utility requirement).
So evidently some people interpret that as 'A' which got me thinking.
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Meh, I think that meets the intent if the length of wiring method inside was as minimal as the length from the entries from the meters to the existing service disconnects. 'Nearest' is up for interpretation, but I don't think any good faith reading let's you run unlimited length inside by arguing over what is an entry or exit.
 
wwhitney said:
Not necessarily if this was done under a code earlier than the 2023 NEC. Wasn't the status of the line-side interconnection conductors as service conductors somewhat ambiguous in earlier code sections, with 690 or 705 even having some special allowances for them?

Cheers, Wayne
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IIRC correctly 2017 had a 10ft limit. 2020 changed that to being treated like service conductors.
 
jaggedben said:
IIRC correctly 2017 had a 10ft limit.
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Yes, thanks, 2017 NEC 705.31, which doesn't specify inside/outside, so outside is fine even when the interconnection is inside, as long as it is within 10'. As it is part of Chapter 7, even if you see the conductors as service conductors under the 2017 NEC (unclear), this may be seen as amending 230.70(A)(1) for such conductors.

Cheers, Wayne
 
jaggedben said:
Meh, I think that meets the intent if the length of wiring method inside was as minimal as the length from the entries from the meters to the existing service disconnects. 'Nearest' is up for interpretation, but I don't think any good faith reading let's you run unlimited length inside by arguing over what is an entry or exit.
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Yeah it was minimal, the job it reminded me of was a large renovation and it was not, so yeah AHJ judgement call.
I have always tried to keep all the disconnects grouped in one location, but if the utility is requiring an outside disconnect and the NEC is not requiring the inside one I can see why they did that.
 
Aren't the service conductors just from the service point to the first disconnecting means?

Maybe I misunderstood, but didn't they put a disconnecting means at the service point when the installed the solar? Or are you saying those conductors run through the house first.

Is it, inverter, conductors inside house, to outside disconnect, to meter? That would make them service conductors until that first disconnect. Though it would require fuses I believe to meet that.
 
Elect117 said:
Aren't the service conductors just from the service point to the first disconnecting means?

Maybe I misunderstood, but didn't they put a disconnecting means at the service point when the installed the solar? Or are you saying those conductors run through the house first.

Is it, inverter, conductors inside house, to outside disconnect, to meter? That would make them service conductors until that first disconnect. Though it would require fuses I believe to meet that.
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He said they tapped in the panel inside, on the line side of the main breaker. So from the utility it goes meter (outside) to service panel (inside) to PV disconnect (outside) with no overcurrent protection until (presumably) it reaches the PV disconnect.
 
Elect117 said:
Aren't the service conductors just from the service point to the first disconnecting means?

Maybe I misunderstood, but didn't they put a disconnecting means at the service point when the installed the solar? Or are you saying those conductors run through the house first.

Is it, inverter, conductors inside house, to outside disconnect, to meter? That would make them service conductors until that first disconnect. Though it would require fuses I believe to meet that.
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Here is a diagram one possible example of interpretation A:
solar_no_group.png
 
jaggedben said:
I beleive the NEC is fine with either of those as long as the distance inside the building is about as minimal as practicable.
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Which version? With the "line side interconnection conductors are service conductors" idea of the 2023 NEC, isn't grouping of the two service disconnects required?

Cheers, Wayne
 
wwhitney said:
Which version? With the "line side interconnection conductors are service conductors" idea of the 2023 NEC, isn't grouping of the two service disconnects required?

Cheers, Wayne
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No because if you carefully parse 230.71(B) I'm allowed to have two sets of up to six disconnects via 230.40 Exception 5 and/or 230.82(6), as referenced in 705, and each set only needs to be grouped with itself per 230.72 . 😁 Mind you I've never had to hash that out with an AHJ, but the code says that.
 
jaggedben said:
No because if you carefully parse 230.71(B) I'm allowed to have two sets of up to six disconnects via 230.40 Exception 5 and/or 230.82(6), as referenced in 705, and each set only needs to be grouped with itself per 230.72 . 😁 Mind you I've never had to hash that out with an AHJ, but the code says that.
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That is the way I heard seen people interpret it at IAEI conference last august. That the interconnected sources need to be grouped but not necessarily near the other disconnects, the utility services need to be grouped but not necessarily with others and arguably the fire pump should not be grouped near others.

@tortuga , I might not accept A if I was responsible for plan check but I don't know if I could site a proper code section. My only issue is what was mentioned previously, Those service conductors conductors are technically unprotected for that unspecified distance. If they were kept short, and specified as less than 10' or whatever I might not have an issue. Though I would have suggested intercepting the utility run and installing a pull box and putting the splices there.
 
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