Using RMC as lighting pole

[Gary Hill]

Hello,

My question concerns using 2" RMC as a parking lot pole light. I have been assigned to work with another electrician who has come up with this design where we are to u-bolt 2" RMC to an existing fence and stick a light fixture on the end. The RMC is to be 15' up.

I can only come up with 430.30(B) as a violation, but we are piping along the fence, and using a junction box at the base of this pole so the splicing would be accessible. It just looks wrong to me. Is this a violation of anything else? Thoughts?

Thanks in advance,

Gary

 

[kwired]

Hello,

My question concerns using 2" RMC as a parking lot pole light. I have been assigned to work with another electrician who has come up with this design where we are to u-bolt 2" RMC to an existing fence and stick a light fixture on the end. The RMC is to be 15' up.

I can only come up with 430.30(B) as a violation, but we are piping along the fence, and using a junction box at the base of this pole so the splicing would be accessible. It just looks wrong to me. Is this a violation of anything else? Thoughts?

Thanks in advance,

Gary

Did you make a mistake with your code section mentioned? There is no 430.30 in 2014 NEC, but even if there was 430 is the section on motors?

My experiences 2-1/2 inch RMC fits many pole mount lighting fixtures just about right, 2" is too small for direct mount of these types of fixtures.
RMC is heavier walled then some of the posts sold for the purpose as well, but that is mostly for posts up to maybe 8 feet tall. Higher then that possibly requires a hand hole in lower portion of the pole - need to look that up to confirm though.

 

[jumper]

I assume you have a typo and meant 410.30(B).

 

[Gary Hill]

yes sorry. fingers slower than brain. I meant 410.30(B)

 

[Carultch]

Hello,

My question concerns using 2" RMC as a parking lot pole light. I have been assigned to work with another electrician who has come up with this design where we are to u-bolt 2" RMC to an existing fence and stick a light fixture on the end. The RMC is to be 15' up.

I can only come up with 430.30(B) as a violation, but we are piping along the fence, and using a junction box at the base of this pole so the splicing would be accessible. It just looks wrong to me. Is this a violation of anything else? Thoughts?

Thanks in advance,

Gary

If you use conduit as a structure, you are not permitted to simultaneously use it for wiring.

Keep in mind that RMC is not the same thing as Schedule 40 pipe. While dimensionally similar, it is a different alloy of steel that has less yield strength than most steel used for plumbing/fence/structural applications. In fact, it is intentionally weaker so you can bend it.

 

[kwired]

I assume you have a typo and meant 410.30(B).

I see hand hole rules I mentioned is in that section.

 

[kwired]

If you use conduit as a structure, you are not permitted to simultaneously use it for wiring.

Keep in mind that RMC is not the same thing as Schedule 40 pipe. While dimensionally similar, it is a different alloy of steel that has less yield strength than most steel used for plumbing/fence/structural applications. In fact, it is intentionally weaker so you can bend it.

In general yes, for signs and lighting you are allowed to use the pole as a raceway in many cases. In this instance the "pole" happens to be made out of an item that is also listed as a raceway. OP is still required to have a handhole near the base of said pole. Making a handhole in a custom made pole made from 2 inch RMC may or may not significantly weaken the pole - depends on conditions it may be subject to, but other then that, nothing prohibits using RMC as the pole.

 

[wwhitney]

In general yes, for signs and lighting you are allowed to use the pole as a raceway in many cases. In this instance the "pole" happens to be made out of an item that is also listed as a raceway. OP is still required to have a handhole near the base of said pole.

410.30(B) gives permission to use a generic pole as a means of support for a luminaire and as a raceway if certain conditions are met.

If the luminaire is sitting atop a bona fide raceway like RMC, then the 410.30(B) raceway permission is not required. If you can also meet the support requirements of 410.36, then none of the 410.30(B) permissions are required, and you don't need to meet the 410.30(B) conditions. In which case no handhole is required.

Cheers, Wayne

 

[kwired]

410.30(B) gives permission to use a generic pole as a means of support for a luminaire and as a raceway if certain conditions are met.

If the luminaire is sitting atop a bona fide raceway like RMC, then the 410.30(B) raceway permission is not required. If you can also meet the support requirements of 410.36, then none of the 410.30(B) permissions are required, and you don't need to meet the 410.30(B) conditions. In which case no handhole is required.

Cheers, Wayne

I guess I agree. The only thing in support requirements of 410.36 that applies to this application would be (E) raceway fittings, if you have a fitting in the installation.

Bona fide raceway like you describe would likely mean you have complete raceway all the way to a junction box, cabinet, etc. at another location, and not a raceway stubbed to the inside of the base of the "pole".

 

[Carultch]

In general yes, for signs and lighting you are allowed to use the pole as a raceway in many cases. In this instance the "pole" happens to be made out of an item that is also listed as a raceway. OP is still required to have a handhole near the base of said pole. Making a handhole in a custom made pole made from 2 inch RMC may or may not significantly weaken the pole - depends on conditions it may be subject to, but other then that, nothing prohibits using RMC as the pole.

I understand completely, the concept of using a listed pole structure as a raceway. Something engineered and tested for simultaneous use as both structure and raceway.

There is a difference between that, and using a homemade pole from standard RMC and a C-body as a handhole. Is this permitted as well, in the case of lighting fixtures?

 

[kwired]

I understand completely, the concept of using a listed pole structure as a raceway. Something engineered and tested for simultaneous use as both structure and raceway.

There is a difference between that, and using a homemade pole from standard RMC and a C-body as a handhole. Is this permitted as well, in the case of lighting fixtures?

I would think 410.36(E) I mentioned in my last post would come into play for the C-body - is is strong enough to take any normal abuse expected to be imposed upon it?

Otherwise I don't see anything stating the pole must be listed for use as a lighting pole (which if used as a lighting pole we can also use as a raceway for the conductors to the luminaire per 410.30(B). Just because RMC is a listed raceway doesn't mean it isn't just a plain 'ol galvanized heavywall tube when used for anything besides part of a raceway system. One could make a pole out of same sized non listed schedule 40 black pipe and still use it in same manner. May want to paint it or something to protect it from corrosion, but is otherwise just as suitable.

I think that is part of reason why they describe requirements of the pole as much as they do in 410.30 - because you can construct your own. If they were required to be listed - there would be no need for as much details - they would be taken care of by listing standards and would already be compliant when you purchase the poles. That doesn't mean there are not listed poles out there though.

 

[GoldDigger]

As long as the RMC is fully supported (weight and torque) above the C-body its strength should not be an issue.

 

[Gary Hill]

So if we are using it as a raceway do the requirements of the raceway article apply, i.e. securing and supporting?

 

[kwired]

So if we are using it as a raceway do the requirements of the raceway article apply, i.e. securing and supporting?

No, you are using it as a pole, which you happen to have permission to use as a raceway for installing conductors, does not mean it is a "raceway system" covered by one of the raceway articles of chapter 3.