supply side PV connection

ggunn

PE (Electrical), NABCEP certified
Well it may be a long way, but given the general statement of 230.40 says "Each service drop, set of overhead service conductors, set of underground service conductors, or service lateral shall supply only one set of service-entrance conductors", what other type of conductor can you connect?
That's circular logic. It boils down to "they are service-entrance conductors because they are service-entrance conductors".
 

iwire

Moderator
Staff member
I don't make Code (directly), I only cite it.

Don't kill the messenger.
:lol:

You are also adding your interpretation to it which is of course what we all do here but it does not make it a code fact.
 

Smart $

Esteemed Member
:lol:

You are also adding your interpretation to it which is of course what we all do here but it does not make it a code fact.
So it appears we need an official interpretation to make it a fact, eh? :slaphead:
 

mpd

Senior Member
230.82 (6) permits PV systems to be connected to the supply side of the service disconnecting means, it does not require service equipment, only #5 requires service equipment and to be installed in accordance with requirements for service entrance conductors, I would think if a supply side PV disconnect was required to comply with art 230 it would be specified in 230.82 (6)
 

Smart $

Esteemed Member
230.82 (6) permits PV systems to be connected to the supply side of the service disconnecting means, it does not require service equipment, only #5 requires service equipment and to be installed in accordance with requirements for service entrance conductors, I would think if a supply side PV disconnect was required to comply with art 230 it would be specified in 230.82 (6)
230.40 Exception No. 5 specifically refers to 230.82(6).

Then there's your own statement "...nowhere in 705.12 (A) does it tell you that all the requirements of art. 230 & 250 apply to those conductors" and §90.3
 

iwire

Moderator
Staff member
So it appears we need an official interpretation to make it a fact, eh? :slaphead:
No, I just was not aware you had been elevated to the position of AHJ.:D

As has been said many times, not all AHJs interpret this the same so IMPO none of us can say what it means.
 

ggunn

PE (Electrical), NABCEP certified
Short of that official interpretation I mentioned, you have little other choice.
"Official" interpretations notwithstanding, I have no other choice, and I have no problem with that. I just need to know ahead of time how the AHJ wants it built so that I don't fail inspections and have to do rework.
 

mpd

Senior Member
230.40 Exception No. 5 specifically refers to 230.82(6).

Then there's your own statement "...nowhere in 705.12 (A) does it tell you that all the requirements of art. 230 & 250 apply to those conductors" and §90.3

230.82 gives a list of equipment that is permitted to be connected to the supply side of the service disconnecting means, the PV supply side disconnect is not another a service disconnecting means per this section
 

jaggedben

Senior Member
And for the fifth (at least) time I still do not see where the San Antonio method for connecting supply side PV is any safer than the way that the entire rest of Texas wants it done. Those rules are for service disconnects and Austin Energy (for one) engineers unequivocally state that the fused disconnect for supply side connected PV is NOT a service disconnect, the connection is NOT a tap, and the disco does NOT contribute to the six handle rule. Incidentally, there is video on Mike Holt's site that says the same thing.
Look, if you want to give me an argument that 250.24(C) ought to be stricken from the code because there's no safety justification for it, I'm happy to listen to that argument. I do not know why that rule was put in and whether it is truly justified and important. But I begin from the assumption that all of these code sections are in there because there was a legitimate safety reason for them. I would need to be presented with an argument concerning each such rule before I accept that it doesn't undermine safety to ignore them.
 

jaggedben

Senior Member
article 230 would not apply for that supply side PV disconnect or wiring method and yes NM-B would be acceptable acceptable as a supply side PV feeder unless it was in a location that NM-B was not permitted per art. 334, I think some of the confusion with this supply side connection is if you want to install as service conductors,service disconnect & service grounding requirements NEC permits it but does not require it, if it is not a shall or shall not then other methods are permitted. I don't think either method is 3 wire PV supply side or 4 PV wire supply side is unsafe.
I don't disagree that the code as-is can be interpreted that way. I just don't understand how it's safe to use NM-B for one set of conductors connected directly to the utility and not for another.
 

jaggedben

Senior Member
The fact that the NEC would allow conductors connected between the PV disconnect and a supply side POCC to be unprotected is not particularly shocking to me. We do similar things all the time with the tap rules, and service entrance conductors are unprotected by default. Whether the connection is made as a feeder or as a service entrance those conductors are going to be unprotected. No way around that.
Normally there's quite a big difference in requirements between conductors installed according to the tap rules and service conductors exposed to the full fault current of the utility transformer with no OCPD in between. That's my whole point.
 

jaggedben

Senior Member
230.82 (6) permits PV systems to be connected to the supply side of the service disconnecting means, it does not require service equipment, only #5 requires service equipment and to be installed in accordance with requirements for service entrance conductors, I would think if a supply side PV disconnect was required to comply with art 230 it would be specified in 230.82 (6)
This is one implicit argument among many. Please see here.
 

Smart $

Esteemed Member
230.82 gives a list of equipment that is permitted to be connected to the supply side of the service disconnecting means, the PV supply side disconnect is not another a service disconnecting means per this section
I'm not saying the PV System disconnecting means is a service disconnecting means. In fact I've always been on the side of the fence that says it is not. I'm only referring to the conductors on the service side of the supply side disconnecting means.
 

Smart $

Esteemed Member
No, I just was not aware you had been elevated to the position of AHJ.:D

As has been said many times, not all AHJs interpret this the same so IMPO none of us can say what it means.
So I suppose then there's no purpose for this forum or your opinion. We should all resort to directly asking the project's respective AHJ and not give any creedence to what anyone says here, including you.

:p
 

mpd

Senior Member
I'm not saying the PV System disconnecting means is a service disconnecting means. In fact I've always been on the side of the fence that says it is not. I'm only referring to the conductors on the service side of the supply side disconnecting means.
then if it is not a service disconnect why would the conductors have to be installed as service conductors
 
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