tap location question

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
I feel like 705.12(A) is the place where all the specifics of this issue should be answered. Such as, is or isn't it a "service disconnect", and should or should not ground and neutral be bonded at it?
Around here it depends on whether you are in Austin or San Antonio.
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
they are service entrance conductors plain and simple.
I disagree. It is neither plain nor simple.

I agree with Carultch. The NEC should explicitly and unambiguously address this issue in 705.
 
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jaggedben

Senior Member
A service disconnecting means implies the utility is supplying power to utilization equipment on the load side of the disconnect. A PV system does not qualify as utilization equipment, and if there is a load side to the disconnect, it is the utility side. So a PV System Disconnect cannot be a Service Disconnecting Means.
1) It's still a service if there are other loads connected to other service conductors.

2) This is why I have suggested that the definition be changed. It is arguably the only important piece of the code supporting this argument, and should just be changed to be consistent with the rest. To be bluntly honest, the only reason I didn't propose it last time around is that I decided that the ambiguity might be to my advantage since I'm likely to know the arguments both ways better than the AHJ. IOW, keeping our options open.
 

jaggedben

Senior Member
I agree with Carultch. The NEC should explicitly and unambiguously address this issue in 705.
I believe this has been proposed before and rejected because the CMP thought the answer was obvious. Lol

Anyway, would you want it to just refer back to article 230, or something else? That can be an open question to everyone.
 

pv_n00b

Senior Member
Location
CA, USA
You might want to read this article in SolarPro from a few years ago. It steps through the NEC showing how PV supply side interconnections are second service entrances so they get a second crack at the 6 disconnect rule. For another view you can also read this article by Holt. He states that supply side PV interconnections are not service entrances so they don't count against the 6 disconnect rule, but I don't agree with this interpretation myself.
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
How can you disagree, it says right in 230.40 exception 5 they are service entrance conductors. Now whether those terminate at a service disconnect, that could be argued....
I disagree with the idea that the issue is plain and simple. I routinely deal with two major municipally owned utilities who are notoriously picky about this and other things, and their respective engineering departments have come to opposite conclusions.
 
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