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Discussion Starter · #1 ·
I'm currently looking at renting space in a building that's under repair near me. I'll be using the space for a millwork/cabinet shop and it's attractive for both the low rent and it's got a 3ph service- no more RPC for a while!
The building is supposed to be "zoned industrial" as per the owner. It was long ago a machine shop but it's in bad shape so the existing wiring is NG. My question to the forum is this- does the single phase wiring (110v) for lighting and convienience outlets have to be unsheathed and in pipe like the equipment wiring? Owner seems to think not and also doesn't want to pay for it; wants to leave it up to me.
 

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I assume you are referring to NM cable (Romex).

If your AHJ has adopted the NEC as the governing electrical code, Google NEC Article 334. It covers NM.

Simple answer---if cannot be exposed.

Tom
 

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I assume you are referring to NM cable (Romex).

If your AHJ has adopted the NEC as the governing electrical code, Google NEC Article 334. It covers NM.
I think he means individual conductors in conduit.
No, this is not required.



Simple answer---if cannot be exposed.
Since when? Do you have a code reference? Because I have one to the contrary, 334.15.


It does not matter how the building is zoned, it matters what the construction rating of the building is. NM cable is not allowed in certain buildings or above drop ceilings in non-residential applications.
 

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As I stated, simple answer it cannot be exposed......

Do you really think it a shop/production/factory setting the conductors will not be at risk for physical damage? 334.15 (B) requirers protection from physical damage. Once the conductors are placed in a protective anything, I don't consider them exposed.

334.15(C) requires that any conductors running down the wall in an unfinished basement be in a listed conduit or tube.

Tom
 

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Do you really think it a shop/production/factory setting the conductors will not be at risk for physical damage?
For the most part no, but it is not that simple.

As I stated, simple answer it cannot be exposed......
Well, the answer is not that simple, so you are wrong, since it is specifically stated that it CAN be installed exposed.

I fail to see how 334.15(C) even remotely applies here. :rolleyes:
 

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It is that simple, any risk of damage, no matter how minuscule or remote requires the conductors be protected.

334.15(B) easily applies.

(C) from the standpoint that if it is exposed/surface mounted and may be damaged it has to be protected/covered.

Tom
 

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I can't really offer and insight.

But. By me, in industrial/commercial warehouse buildings, MC cable is king. They even have mc running down Collums to boxes, etc.

Seems like anything larger than #6 is hard piped.
 

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It is that simple, any risk of damage, no matter how minuscule or remote requires the conductors be protected.
True

334.15(B) easily applies.
Of course it does.


(C) from the standpoint that if it is exposed/surface mounted and may be damaged it has to be protected/covered.
No. It. Doesn't. Apply.
Not unless there is an unfinished basement or crawl space in this industrial building. :rolleyes:

We're getting off on a tangent here. I highly doubt I'd use NM cable there either. I was just correcting your statement that it could not be exposed at all.
 

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I can't really offer and insight.

But. By me, in industrial/commercial warehouse buildings, MC cable is king. They even have mc running down Collums to boxes, etc.

Seems like anything larger than #6 is hard piped.
Funny thing is, MC cable offers no more protection than NM cable in the eyes of the code.
 

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Discussion Starter · #10 ·
Yes, I did mean NM cable; owner seems to feel that if "covered" i.e. in pvc conduit, it's ok.
I was under the impression that it could only be used in frame walls and ceilings that were sheetrocked and taped.

I also thought that MC was allowed exposed. I've got a bunch of 12/3 too.

Getting back to it-
I'm going to need to install lighting. While the joists are still exposed. I could run NM and terminate in boxes?. But if going over the drywalled ceiling(10'high), I'll still need pipe and THHN for the fixtures?
 

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Don't confuse zoning with building or electrical code. Zoning is only there to keep everything in it's place, i.e., stores and restaurants in one part of town, houses in another. People don't want to have shopping malls in their back yard.

Building code goes by occupancy type, you're probably talking about a type B occupancy. I don't know how it applies to electrical code but you can get your answer with a simple phone call to your electrical inspector. It's hard to answer wiring questions here because electrical work has a lot of town specific requirements that go beyond the NEC. One I know of is in Chicago, they have to use conduit everywhere. Which I've seen brought up on these forums quite a bit. Another rule I've come across around here is if you are framing a four story condo, the cables going to each electric panel have to be in conduit. If it's a three story condo, they do not. Then the definitions of three or four story condos can be vague. If the building has three levels but the top units have stairs going to an upper floor, then it's considered a three story building even though it's framed like a four story. So a whole new set of electrical requirements apply. The bottom line is, as with building code, just ask the guy that's going to inspect it. He's the one making the interpretation, you don't really need to talk to anyone else.
 

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Under the NEC Article 500.5(C), the shop would be a ClassII, Division I location. 500.5 covers hazardous dust.

You can only use NM in your application if you install it per Article 502.10(B)(3).

What are the light fixtures?

I'm from Chicago, another one for you--the only person who can pull an electrical permit in Chicago is a City of Chicago licensed electrician. The property owner cannot obtain an electrical permit (unless of course they're a city licensed electrician).



Tom
 

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3ph power............



I have dreams of a 3ph line being installed in my shop......literally....


Now you have the true 3ph ..:thumbsup:....rotary phase converters.....great source for 3ph from single (as you know), the downfall is they tend to be a little noisy.....



3ph machinery runs so much better than single phase - IMO ...:thumbsup:


As far as the wiring,.....Do it write , it will look cleaner as well (tubed) JMPOV.

Hope all goes well.....


On a side note,

What machinery are you running on 3ph (make-model)..anything OWWM..:blink:
 

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Discussion Starter · #16 ·
On a side note,

What machinery are you running on 3ph (make-model)..anything OWWM
Yep- Oliver TS, mortiser, planer, Northfield shaper, Crescent jointer and various others.

Other problems though, I'm starting a different thread for it.
 

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Here buildings are classified combustible and non combustible. That's your first step in deciding whether you are allowed to use NM or not.
 

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What kind of a building is noncombustible?
 
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