SER for commercial use

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Daja7

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I think this has been covered a while back but some new code changes may be in place. I have a customer that wants two new sub panels in his building but wants to keep costs down by using SER
It seems that this may not be code legal but not sure. Building is part office space with suspended ceiling and part ware house open with bar joist. This bldg. is for parts warehouse and sales.
Any thoughts? I can't decipher for sure.
 
Article 338.10(B)(4) tells us we must use art. 334 Part II excluding 334.80.

Part II-- art. 334.12 (A)(2) tells us SER cannot be used in suspended ceilings except in dwellings. So IMO, you cannot use SER.
 
Dennis Alwon said:
Article 338.10(B)(4) tells us we must use art. 334 Part II excluding 334.80.

Part II-- art. 334.12 (A)(2) tells us SER cannot be used in suspended ceilings except in dwellings. So IMO, you cannot use SER.
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Never looked at it that way..... I've overlooked that a time or three.....
 
Daja7 said:
what about open ceiling with bar joist?
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I've approved it, but in light of Dennis' revelation I think it is not Code compliant based on not "following the building surface'.
I'll be glad to see what others say.
 
I wired a whole business park (approx. 28 tenant spaces) and used 4/0 3-phase SER for all the subpanels. The buildings were 4 units each, with a 4-pack meter can/mains. All the buildings were wood structure, including roof trusses.

The inspector rightfully didn't want to see any SER or NM cable "in" the grid ceiling. He said "no rag cable" (reference to old cloth sheathing?)

But I argued that "in" the ceiling would technically be from the grid to the eyelets. Above the eyelets is above the grid ceiling, not in it. He agreed that I could run my rag cables in the trusses, not anywhere below. So anywhere the panels were installed, the wall had to extend all the way to the trusses, so that the cable could enter the wall without going below the trusses

I would suspect that bar joists should be treated differently from wood, though. Even if not prohibited, I probably wouldn't use sheathed cable in a metal structure
 
James L said:
But I argued that "in" the ceiling would technically be from the grid to the eyelets. Above the eyelets is above the grid ceiling, not in it. He agreed that I could run my rag cables in the trusses, not anywhere below. So anywhere the panels were installed, the wall had to extend all the way to the trusses, so that the cable could enter the wall without going below the trusses

I would suspect that bar joists should be treated differently from wood, though. Even if not prohibited, I probably wouldn't use sheathed cable in a metal structure
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I am surprised the inspector bought that reasoning
 
I am going to answer this question in a different way.

Yes you may use SER for commercial jobs if you keep it out of suspended ceilings and it is behind at least a 15 minute wall finish.
 
iwire said:
I am going to answer this question in a different way.

Yes you may use SER for commercial jobs if you keep it out of suspended ceilings and it is behind at least a 15 minute wall finish.
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:thumbsup:

old dogs can learn new tricks :)
 
I appreciate the replies, I don't like the SER concept here but owner wanted to investigate the possibilities.
I am pricing pipe and wire. He can accept it or not.
 
Daja7 said:
I appreciate the replies, I don't like the SER concept here but owner wanted to investigate the possibilities.
I am pricing pipe and wire. He can accept it or not.
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(or get an inspector who hasn't read this thread :D )
 
IWIRE has it right -- non accessible type ceiling or drops / concealed spaces -- be careful when penetrationg rates assemblies.
 
Daja7 said:
I appreciate the replies, I don't like the SER concept here but owner wanted to investigate the possibilities.
I am pricing pipe and wire. He can accept it or not.
Click to expand...
maybe offer an MC feeder option as well?
 
iwire said:
I am going to answer this question in a different way.

Yes you may use SER for commercial jobs if you keep it out of suspended ceilings and it is behind at least a 15 minute wall finish.
Click to expand...
I've run it in commercial, usually wood framed office buildings. If we ended up in the drop ceiling we boxed around the runs with 2X furring and covered it with drywall.

One time we ran it inside the joists since all bays were to be filled with fibreglass insulation between floors for sound damping, which was good enough for the inspector to sign off on it as not being exposed above the ceiling tiles.
 
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