300.4 Protection Against Physical Damage.
Where subject to physical damage, conductors shall be protected.
The RGS is protecting the conductors.
Rigid installed on top of concrete floor?
- Thread starter hardworkingstiff
- Start date
- Status
300.4 Protection Against Physical Damage.
Where subject to physical damage, conductors shall be protected.
The RGS is protecting the conductors.
344.30 08 code
the rgs is not adequately protecting the conductors when you allow automobiles to drive over the conduit on a daily basis, and that is why it would never pass inspection
- Location
- Massachusetts
You can not just decide that, you need to provide a code reference.
The NEC allows the use of RMC in areas subject to damage.
- Location
- Massachusetts
That section addresses securing, he will be able to secure the conduit.
So, if I am installing highway lighting I can just take conduit and support it to the concrete road and cross all 3 lanes to feed the light on the other side? What a time saver, thanks
Define 'securely supported' with respect to the forces of an automobile being applied to it.
ptonsparky
Tom
- Occupation
- EC - retired
big john
Senior Member
- Location
- Portland, ME
This is one of those installations that if it works, I'd have to see it to believe it.
Right now, I simply don't believe that a piece of 1/2" RMC would be in any kind of decent shape after being run over multiple times a day, every day. At very best, I think you'd get maybe a year out of that type of installation.
I think getting some sort of road-plate would be a much better option than trying to secure the heck out of the piece of rigid.
-John
Right now, I simply don't believe that a piece of 1/2" RMC would be in any kind of decent shape after being run over multiple times a day, every day. At very best, I think you'd get maybe a year out of that type of installation.
I think getting some sort of road-plate would be a much better option than trying to secure the heck out of the piece of rigid.
-John
- Location
- Massachusetts
If a piece of RMC falls through the asphalt or concrete it is being supported by we have a bigger problem than the discussion at hand.
What support would be better in your opinion?
Roger
In your opinion, this is a 'physically protected' conductor.
I can think of a few times on construction sites where this very situation has been in place with rubber tired traffic for upwards of a year and maybe even over a year where the conduit was still in good shape (with the exception of being dirty) when we removed it.
Now run a trackhoe over it and things change.
The great thing about this is not having to meet the requirements of 300.5
Roger
With respect to SECURELY supported, I do not know of any support method that could be utilized to mount a RGS conduit on a 3 lane, concrete highway.
When referencing securely supported, what factors do you consider in order to state that it is, in fact, securely supported? Are there other factors that come in to play (lets say your installing wiremold, or perhaps a rack with 8- 4" RGS conduits with each filled to the max with 500 mcm) when securely supporting RGS?
macmikeman
Senior Member
- Location
- Planet macmikeman
This sure got off track fast.... The op was talking about a vehicle lift station inside a vehicle garage. The rigid conduit on the surface of the deck at the spot just before the cars go onto the lift should last decades, providing it doesn't rust due to lack of corrosion protection. You know, it also would not be a great idea to put it across a three lane highway, nor would it be a great idea to put it up 20 feet in the air across an airport runway either.... a bit of common sense would be fair to use in judgement.
This sure got off track fast.... The op was talking about a vehicle lift station inside a vehicle garage. The rigid conduit on the surface of the deck at the spot just before the cars go onto the lift should last decades, providing it doesn't rust due to lack of corrosion protection. You know, it also would not be a great idea to put it across a three lane highway, nor would it be a great idea to put it up 20 feet in the air across an airport runway either.... a bit of common sense would be fair to use in judgement.
I agree with the common sense portion, but installling a 1/2" RGS conduit and allow automobiles to drive over it on a daily basis, in my HO, is against code because it does not adequately protect conductors and it is not securely supported.
- Location
- Illinois
- Occupation
- retired electrician
I just don't understand how something that is resting on a concrete surface is not securely supported.
I would have no issue with this size conduit being used in this application. It will provide plenty of protection for the installed conductors.
Tell me where the term "SECURELY supported" is used in the NEC.
What you are trying to do is read something into the NEC that doesn't exist.
With that said, "securing" and "supporting" are two different requirements and the word support is defined as
The concrete floor had better be able to support to RMC or as I said earlier, we have a bigger problem than the discussion at hand.
What you are trying to argue for is the securing issue, this could be handled a number of ways.
It is normal to automatically think something isn't allowed because it is not seen everyday but, in this case, there is nothing in the NEC that would prohibit it and we are discussing this in the NEC forum.
If we had a "What would you like the NEC to say" forum we could go with the "it ain't allowed" mind set.
Roger
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