PV supply side tap conductors

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Wilg

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When the PV conductors are tapped ahead of the main service disconnect and ran through the building... how far can they be ran before fusing them again?

Mostly concerned when to conductors are being ran through a building more than a few feet. We allow 6' or so into the building for normal service conductors as long as they are physically protected.

I questioned an installation recently and the PV installer thought I was crazy to suggest fusing the wires a second time near the supply side tap.

Just wondering what you guys are seeing out there.
 
Wilg said:
When the PV conductors are tapped ahead of the main service disconnect and ran through the building... how far can they be ran before fusing them again?

Mostly concerned when to conductors are being ran through a building more than a few feet. We allow 6' or so into the building for normal service conductors as long as they are physically protected.

I questioned an installation recently and the PV installer thought I was crazy to suggest fusing the wires a second time near the supply side tap.

Just wondering what you guys are seeing out there.
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The tap conductors must follow the rules for service entrance conductors up to the PV system disconnecting means.
 
My last post doesn't say much, does it? :p

In the 2011 NEC, I do not believe there is any stipulation as to how far into or through a building these conductors can be run. I believe this is the very reason 2014 NEC added 705.31.
 
Thanks, it was a rambling question....I know what I'd "like" to see but we're still in the 2011 NEC. I'll check the 2014 language.

I always hated when inspectors said "Cause I said so"......so I try not to do that now that I'm on the other side of the clipboard :D
 
Wilg said:
When the PV conductors are tapped ahead of the main service disconnect and ran through the building... how far can they be ran before fusing them again?

Mostly concerned when to conductors are being ran through a building more than a few feet. We allow 6' or so into the building for normal service conductors as long as they are physically protected.

I questioned an installation recently and the PV installer thought I was crazy to suggest fusing the wires a second time near the supply side tap.

Just wondering what you guys are seeing out there.
Click to expand...

Maybe I don't understand your question. 705.31 says you must have OCPD within 10' of the point of interconnection. That's all the OCPD you need on those conductors; fusing a second time accomplishes nothing.
 
ggunn said:
Maybe I don't understand your question. 705.31 says you must have OCPD within 10' of the point of interconnection. That's all the OCPD you need on those conductors; fusing a second time accomplishes nothing.
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He's on 2011. There is no 705.31.
 
Wilg said:
When the PV conductors are tapped ahead of the main service disconnect and ran through the building... how far can they be ran before fusing them again?

Mostly concerned when to conductors are being ran through a building more than a few feet. We allow 6' or so into the building for normal service conductors as long as they are physically protected.

I questioned an installation recently and the PV installer thought I was crazy to suggest fusing the wires a second time near the supply side tap.

Just wondering what you guys are seeing out there.
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Safest way is INSIDE NEAREST THE POINT OF ENTRANCE into the building.
 
electrofelon said:
I think there is some confusion as to whether the op is talking about the conductors on the utility or customer side of the pv disconnect.
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Perhaps. The "fusing second time" muddles the picture.

If the tap is fused at the point of interconnection, the discussion becomes moot, as we can run feeders 'dern near' anywhere.

I believe he is talking about on the utility side, as I do not know of any requirement in the 2011 NEC that says you can't run service taps for PV through a building or that limits the distance into which you can run them prior to having overcurrent protection. With a service, the location of the service disconnecting means is specified as outside or inside nearest the point of entrance. There is no equivalent for the location of a PV system disconnecting means with overcurrent protection.
 
Smart $ said:
Perhaps. The "fusing second time" muddles the picture.

If the tap is fused at the point of interconnection, the discussion becomes moot, as we can run feeders 'dern near' anywhere.

I believe he is talking about on the utility side, as I do not know of any requirement in the 2011 NEC that says you can't run service taps for PV through a building or that limits the distance into which you can run them prior to having overcurrent protection. With a service, the location of the service disconnecting means is specified as outside or inside nearest the point of entrance. There is no equivalent for the location of a PV system disconnecting means with overcurrent protection.
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It's certainly possible that an AHJ will view the conductors as another set of service entrance conductors and enforce the outside or inside nearest the point of entrance requirement.
 
jaggedben said:
It's certainly possible that an AHJ will view the conductors as another set of service entrance conductors and enforce the outside or inside nearest the point of entrance requirement.
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They are service entrance conductors. But the AHJ can only enforce 'outside, inside nearest' rule if he considers the PV system disconnecting means is a service disconnecting means.
 
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