Under the NEC or Not?

[Little Bill]

A new gray area.

Most of us accept if we bring a listed generator to a property and connect it permenantly to electrical equipment in a building the NEC would apply so why don't you think it applies here?

So how would you make the install comply? What would you use for OCPD and disconnect? The inspector didn't want the rigid ran into the solar panel, just close to it, then add a bushing on the end and seal it. The rigid would then run inside to a disconnect with OCP.
Then from the disconnect to the fan using MC cable. If you use MC you would have to cut the wire, thus voiding the mfg. listing (if there is one).
I also can't find in the NEC where it states "rigid" must be used. All I see is "metal raceway."
I personally don't think the inspector knows anymore than I do about PV systems, which in my case is little to none.
That is why I said to ditch the fan!

[jim dungar]

According to the OP, the fan runs on DC directly from the solar array. Everything I see in the scope of 690, involves an inverter to AC.

[jxofaltrds]

So how would you make the install comply? What would you use for OCPD and disconnect? The inspector didn't want the rigid ran into the solar panel, just close to it, then add a bushing on the end and seal it. The rigid would then run inside to a disconnect with OCP.
Then from the disconnect to the fan using MC cable. If you use MC you would have to cut the wire, thus voiding the mfg. listing (if there is one).
I also can't find in the NEC where it states "rigid" must be used. All I see is "metal raceway."
I personally don't think the inspector knows anymore than I do about PV systems, which in my case is little to none.
That is why I said to ditch the fan!

Don't know about Tenn. but in Ohio an inspector MUST cite what he is failing you on. Not just it's in the book or article 690.

Like 690.4(F). That way you know what you have to fix.

[Little Bill]

Don't know about Tenn. but in Ohio an inspector MUST cite what he is failing you on. Not just it's in the book or article 690.

Like 690.4(F). That way you know what you have to fix.

I actually haven't been failed. I got called into this because they had two failed inspections. They had two different electricians (maybe electricians) that wired the barn. After the second one the owner decided to get some recommendations for electricians from another source. That's when I was called in. I read the inspectors list and had no trouble finding/fixing the other items but when I came to the PV part, all he said was " solar needs to be wired according to the NEC". I called him and he wasn't specific about much other than the use of rigid and MC. He couldn't tell me what he wanted for OCP or disconnect.


How come no one has asked about the "critters"?

[Hv&Lv]

How come no one has asked about the "critters"?

Bet those would make little bitty hams. And the bacon would be real short too.

[Little Bill]

Bet those would make little bitty hams. And the bacon would be real short too.

Maybe not too short!

[jaggedben]

Let's suppose for a second that this is under the NEC (and is not a listed, self contained device). All of the inspector's requests are STILL RIDICULOUS.

1) Raceway is not required for source circuits under 30V. 690.31(A). The only thing he's got is 690.31(E), and that is only inside the building.
2) RMC has never been required. EMT has always been allowed in 690, and the last couple iterations of the code have allowed other raceways and methods as well.
3) Overcurrent protection is not required for this setup regardless of voltage. See the exceptions in 690.9(A).
Those exceptions are there to recognize that overcurrent protection is patently ridiculous for this setup, because the panel cannot produce more current than the fan uses.
4) Disconnecting means are required specifically to 'disconnect conductors of the PV system from all other conductors in a building or other structure.' 690.13 Since the conductors of this device are not connected to any others, no disconnect is necessary.

The most you would have to do to make this compliant is to put the wire inside the building in a raceway, e.g. EMT. It might be easer to just move the wire from the inside to the outside. :-D The inspector needs an education on 690. If he's using the NEC as his standard, hold him to the NEC.

[drbond24]

Those are the cleanest, driest pigpens I've ever seen! What happened to wallowing the mud? Is that not politically correct now?

[Little Bill]

Let's suppose for a second that this is under the NEC (and is not a listed, self contained device). All of the inspector's requests are STILL RIDICULOUS.

1) Raceway is not required for source circuits under 30V. 690.31(A). The only thing he's got is 690.31(E), and that is only inside the building.
2) RMC has never been required. EMT has always been allowed in 690, and the last couple iterations of the code have allowed other raceways and methods as well.
3) Overcurrent protection is not required for this setup regardless of voltage. See the exceptions in 690.9(A).
Those exceptions are there to recognize that overcurrent protection is patently ridiculous for this setup, because the panel cannot produce more current than the fan uses.
4) Disconnecting means are required specifically to 'disconnect conductors of the PV system from all other conductors in a building or other structure.' 690.13 Since the conductors of this device are not connected to any others, no disconnect is necessary.

The most you would have to do to make this compliant is to put the wire inside the building in a raceway, e.g. EMT. It might be easer to just move the wire from the inside to the outside. :-D The inspector needs an education on 690. If he's using the NEC as his standard, hold him to the NEC.

Thanks Jag, I was hoping someone familiar with solar installs would chime in. I found a couple of the sections you cited but I'm not knowledgeable enough of this area to be sure.
I have no problem fixing/changing things required by an inspector when he can show me specifically what he wants with code sections to back it up, and I feel confident he knows what he is talking about. It was painfully obvious from talking to him that he didn't know/understand the solar (PV) section of the code. I think this was something he had never ran into and rather than search it out on his own, he just failed it. Then only saying, "do it according to the NEC".

[iwire]

According to the OP, the fan runs on DC directly from the solar array. Everything I see in the scope of 690, involves an inverter to AC.

Which is why I say we are entering a gray area. As I understand it the idea of metal conduit and or outdoor disconnect is the protection of firefighters.

Now I think we can all agree this tiny system does not pose much of a danger but at what point would you say it does? How large of a 'plug and play' PV system should we be able to install without the NEC applying?

What should be the max voltage?

What should be the max short circuit current?


I really do not know if the inspector is right or not, all I am saying is that I don't think it as anywhere near as cut and dry as some seem to. I think the biggest issue is that it is a surprising idea and therefore dismissed without thought.