What is an Approved PVC Strap

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Wow! I may be mistaken but this one sure seems much ado about nothing.
At 28" you are below the requirement for an expansion joint (352.44), and, although I don't disagree with Bob as to 352.30 technically applying, as he says, it seems to be un-needed.
No one can guarantee what your inspector will accept, but this case I'd be tempted to use a 2 hole strap with some washer spacers to keep it form being snug on the PVC but that may be to "jerry-rugged" for your inspector.
 
hardworkingstiff said:
OK, it's listed for PVC, but I don't think it said it allowed movement (maybe I missed it). So if you use this strap, do you have to install an expansion coupling between each strap?
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How about an expansion coupling between each strap that is clamped tight enough to provide the vertical support you asked about and the rest loose enough to allow movement from thermal expansion?
 
augie47 said:
280 ???......
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Sorry, not wearing my glasses, I merged 180 and 200.
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But check out Table 300.19 it is confusing in the AL column. :confused:
 
augie47 said:
see at 352.30(C), revised in '08
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Yes I forgot about that (still installing to 2005 code here so doesn't apply to me yet)

Same requirement for other raceway types also. Very stupid change.

Lets say you have a 4 inch RMC 20 inches long between 2 enclosures. Now you will be required to put a strap on this. Do you really think the strap will do any supporting. The conduit will support the strap. Take a 16 pound sledge hammer and just start beating the hell out of it and I bet the RMC only has some scratches and minor surface dents but the strap will be demolished.

Same would be true for 1/2 RMC except the sledge hammer incident will result in more damage to raceway, but the strap will give up long before there is much damage to raceway.
 
Thomas and Betts Superstrut P-716 series cushioned strut straps WORK AWESOME for pvc on strut. I used some of their 1 1/8" OD straps on some 3/4" pvc, the pipe was just loose enough that it could slide back and forth.

I found them in Grainger first but they wanted around $9 a strap for regular zinc.:roll: Called our local electrical supply house and got them for around $5 and it only took 3-4 days to get them. They offer them in stainless, galvanize and regular zinc I believe.

I'm going to post this in another thread I started also looking for some good pvc strut straps.
 
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So if the strap isn't actually needed in this case, take it off and call the inspector back.

You two will soon be the bestest of friends. :grin:
 
There's only one centered strap! What movement does the inspector expect??? :confused:

Simple fix: place enough washers on the bolt between the straps to be a hair loose.
 
Cow said:
Have you read 352.30?

It only requires straps that allow the conduit to expand and contract, pvc straps are just one option.
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Isn't the strap required to be listed for use with the type of conduit it's supporting?
 
BLACK4TRUCK said:
Geez.. talk about splitting hairs.. that pipe will expand 1/4 inch either side of the strap
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First day here or what? :grin:

mivey said:
Especially since he would need a 264?F change to get 1/4" expansion in 28".
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Looking closely at 352.30 it does not mention how much movement only that it the support must allow it. If there is any temperature change there will be expansion and contraction.

Basically it says what it says and does not allow for commonsense. :)

The 1/4" rule is only found in 352.44.
 
kwired said:
for attaching a grounding conductor.

3. The requirement for an EI to give a code reference for violations of the code are up to the AHJ and lawmakers. I would like to think that it is required most everywhere. Otherwise it allows the inspector to make up his own code. If you are going to have rules you need to be able to provide a reference to them to prove that the rules have been broken otherwise why have the rules?

Just saying "you violated the NEC and the rules are in there somewhere" I suppose could work, but now you either give in and do as inspector requests or you get your book out and try to prove the inspector wrong.
An inspector that can not get out a code book or local amendments to that code and find an article to show you your violation is incompetent and should not be an inspector.
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Constitutional mandates -

Amendment VI

In all criminal prosecutions, the accused shall enjoy the right to a speedy and public trial, by an impartial jury of the State and district wherein the crime shall have been committed, which district shall have been previously ascertained by law, and to be informed of the nature and cause of the accusation; to be confronted with the witnesses against him; to have compulsory process for obtaining witnesses in his favor, and to have the Assistance of Counsel for his defence.

Seems to me the spirit of the law is indicative of citing.

States rights are lower in the food chain than the fed. So would assume the AHJ region should alredy have considered this prior to the righting of any laws dictating to jnspection.

I know it is important to know when to pick your battles....But if an inspector can't produce a law backing his "judgement call" (and going against solid logic), and it matters. Sometimes you have to draw the line.

What say you inspectors, as to how your jurixdiction makes the call? Not emotionl, just curious as to what is going on in other places.
 
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