Has anyone seen or installed 15 amp circuits in commercial buildings? I have never seen one, only 20 amp and up.

Not a common pratice to say the least....
Off the top of the head, can't see why not either.

The answer I picked up somewhere was that commercial systems generally have a higher AFC than residential. During a fault, less chance the #12AWG would fail than the #14.

However, seems to me properly sized and coordinated OCPDs would do their job and protect #14 just as well as #12. Not sure 5 amps makes all that much difference, anyway.



-John

[This message has been edited by BigJohn (edited 05-16-2006).]

I suspect it has more to do with the fact that you have the 180va per outlet restriction in commercial (and perhaps that there is not usually much #14 on a commercial wire cart). It would make sense if this was a dedicated circuit for some low current equipment though. From a safety standpoint, oversizing a circuit (and OCP device) is not always a good idea.

Yes! I have put 15 amp ckts. in commercial! I wired a pool house for an apartment complex, and used #14 for several of my lighting ckts. Code does allow this.

Our local addendums specifically prohibit it.

GEC-1 what you describe is not IMO commercial.

That said the NEC certainly does not prohibit it.

The reason I ask is someone added some walls and wired some church offices in
14-2 romex. Probably be ok, not much load there. The walls are wood construction too. I could change the breaker to a 15 amp.

I work at a very large industrial manufacturer and we have many 15A circuits. While many locales prohibit it. I think often times, it is just a matter of how the wiring is spec'd rather than an NEC issue.

[This message has been edited by IanR (edited 05-17-2006).]

Aldav53, I need some clarification, in your first post you ask, and then in your second post you say,
What you appear to have is # 14 over fused and in violation of 240.4(D), you must change the breaker(s)

With that said, there is no problem as far as the NEC is concerned with having 15 amp circuits in commercial installations if the wiring meets or exceeds the OCPD.

Even in areas where #12 is the minimum size conductor for branch circuits or feeders it would not prohibit protecting the conductors at 15 amps or lower, and infact, certain equipment may have a Max circuit protection below 15.

Roger

I have been compelled to re-breaker commercial circuits down to 15A when the modular end-use equipment is pre-wired in #14.

Think grocery store cash register checkout assemblies. They're all pre-fabbed.

Isn't romex prohibited in a place of gathering,ie. a church?? I use 15 amp circuits all the time in the gas pump world(although I generally use #12 wire) and I suspect with the price of wire the way it is I'll use more with #14 instead.

I almost done replacing the #14 romex that was put in by a handyman previously.
I'm using #12 MC cable for these church offices. Its been a lot of work, lot of holes cut in the drywall, but it will be correct now.
The fluorescent lights are 277 volt also, which had some 14-3 romex used. All will be #12 MC cable.

Not that 12/2 MC is bad but 14 NM may have been fine.

Church offices are not normally a place of assembly.

Aldav53, I agree with Iwire, IMO you did of alot of unnecessary work.

Roger

iwire,
I realize that and agree, it would have probably been fine. But I called the city and they said no romex in commercial. I told the guy heading the project up, so he said change it.
(I also found some NM wire nut splices, no boxes too, in the attic).

If the office is in the church, what difference does it make if the office is a place of assembly?? One doesn't consider the whole building a place of Assembly?? In this case I have no idea if the office is within the church building or not

No you don't necessarily have to call the entire building a place of assembly.

Only the areas that can hold more than a 100 people and are not separated from that area by firewalls.

It is entirely likely that offices, dressing rooms, bathrooms hallways etc would be separated from the 'place of assembly'.

You can wire it entirely as a place of assembly but that may make your bid extremely high compared to an EC that is not wiring it all as a place of Assembly.

Its not in the place of assembly, the Worship center, but the offices are in the same building that the gym and youth rooms are.

Seperation by a fire wall is the key. I wonder how many old churches have a fire wall between offices and the place of assembly? I'd guess not many at least in my area.

All of the original wiring everywhere is done in pipe.

If you are using minimum 20amp branch circuits in commercial, how are you effectively protecting a 15 amp receptacle? I am a Canadian electrician, so maybe you are using 15/20 amp rated receptacles in the States. That being said, common specs for commercial construction calls for minimum 12 gauge but that is usually needed anyways for derating purposes in conduit.

Bare in mind that the assembly ocupancy is only an issue if it is built of one hour construction.

What is one hour construction. A fire rating I assume.

jay8,
Off the subject a bit, but, I believe you are allowed to use 15a recepts in 20a residential kitchen general recepts as long as it is not an individual 20a circuit for one outlet. I have seen it done, I'm I correct on this?