Strapping code

[captainwireman]

In the 2011 code is it really necessary to strap a 1/2 inch x 1 inch long EMT nipple between panels? I am going blind trying to find the exception but it appears this is the new code requirement.

 

[infinity]

What code section is that one?

 

[Billybob1]

Strapping code

From what I can find, in the 2011 edition NEC, 358.30(C) has been omitted.

I guess you are correct to assume it does require a strap.

I will look more to see if I can find more, since if it is 18'' or less it is considered a nipple.

 

[captainwireman]

Reply

Reply

What code section is that one?

358.30 gives no information or exception. Chapter 9 Note 4 does not address this issue either. (2011 NEC)

Now I am really losing it. I can not find the exception for RMC either!

I really don't want to go to "workmanlike installation" if it is not code.

If this is the case, I know a butt head or two that I am going to cite and make them do the installation properly but I had better know what I am talking about first.

Thanks

 

[captainwireman]

Geez!

Geez!

So where are we gong with this? A close nipple between panels that a UL listed strap will not even fit on is now a violation???

 

[Hv&Lv]

(A) Securely Fastened. EMT shall be securely fastened in
place at least every 3 m (10 ft). In addition, each EMT run
between termination points shall be securely fastened within
900 mm (3 ft) of each outlet box, junction box, device box,
cabinet, conduit body, or other tubing termination.

Wouldn't this take care of that situation? If the boxes are a fraction over 36" from each other then a strap would be required IMHO.

 

[ceb58]

In a code change book I have what they are talking about is.
For the 2011 the section that had the 18'' rule has been deleted, the support requirements go back to the 36'' from enclosure. So if there is less than 36'' between enclosures there is no need for a strap.

 

[kwired]

In a code change book I have what they are talking about is.
For the 2011 the section that had the 18'' rule has been deleted, the support requirements go back to the 36'' from enclosure. So if there is less than 36'' between enclosures there is no need for a strap.

I think this was a change in the 2008 NEC that when I went to CEU classes with 2008 changes being main focus of the class we did discuss this. Take 344.30(C) for example. It requires a nipple 24 inches long to have a support, yet the general support rules don't require one for 3 feet and in some cases more than that. 344.30(C) has been deleted from 2011. I remember the discussion of the possibility of having a 4 inch RMC 24 inches long between two cabinets requiring a strap and most of the class agreed that the nipple would be supporting the strap much more so than the strap would ever be supporting the nipple.

 

[hurk27]

I do believe it did return to the 36" before a support is required, but I cant believe they just deleted C as it required it to be unbroken (no couplings) and no reducing washers, which I can understand, but to totally remove this when it was just added for the 2008 cycle is strange, maybe I'll look up the ROP's on this and see why?:?

 

[don_resqcapt19]

The current code wording, and the wording in codes prior to 2008, require a strap no matter how short the nipple is. The rule in the 2008 code was an attempt to make the code match the real world installation practices. The current wording does not imply that a support is not needed if the nipple is less than 36". It only says that you must support withing 36" of the conduit termination. There is nothing in the raceway articles to suggest that the conduit termination itself can be used as a support. The CMP should have accepted the original proposal for the 2008 code which would have eliminated the requirement for a support where the conduit was less than 36" long.

 

[kwired]

The current code wording, and the wording in codes prior to 2008, require a strap no matter how short the nipple is. The rule in the 2008 code was an attempt to make the code match the real world installation practices. The current wording does not imply that a support is not needed if the nipple is less than 36". It only says that you must support withing 36" of the conduit termination. There is nothing in the raceway articles to suggest that the conduit termination itself can be used as a support. The CMP should have accepted the original proposal for the 2008 code which would have eliminated the requirement for a support where the conduit was less than 36" long.

The problem is it is hard to write one statement that covers all real world situations. Tell me how likely a 5 foot length of 4 inch RMC between two cabinets is going to be damaged without some damage to the cabinets also, it doesn't really matter if there is a strap or not. Now put a 1/2 inch RMC in same situation and it is more likely to sustain some damage if not supported, 1/2 EMT even more likely.

True as it was worded, and is again, one could interpret a close nipple between two enclosures as requiring an additional support besides the termination points.

 

[don_resqcapt19]

...True as it was worded, and is again, one could interpret a close nipple between two enclosures as requiring an additional support besides the termination points.

I don't even think there is any interpretation required...the wording clearly requires a support no matter how long the raceway is.
Too late for a 2014 proposal.
"Exception: Unbroken lengths of raceway, install between two fixed enclosures, measuring 36" or less, shall be permitted to be supported by their conduit terminations."

 

[tkb]

I don't even think there is any interpretation required...the wording clearly requires a support no matter how long the raceway is.
Too late for a 2014 proposal.
"Exception: Unbroken lengths of raceway, install between two fixed enclosures, measuring 36" or less, shall be permitted to be supported by their conduit terminations."

How about this,

"Exception: Unbroken lengths of raceway, without any bends, installed between two fixed enclosures, measuring 36" or less, shall be permitted to be supported by their conduit terminations."

 

[kwired]

I don't even think there is any interpretation required...the wording clearly requires a support no matter how long the raceway is.
Too late for a 2014 proposal.
"Exception: Unbroken lengths of raceway, install between two fixed enclosures, measuring 36" or less, shall be permitted to be supported by their conduit terminations."

So do/would you require a strap on a close nipple? It fits the description of what needs secured.

 

[don_resqcapt19]

So do/would you require a strap on a close nipple? It fits the description of what needs secured.

The code requires the strap...I don't think the CMP really understands the issue that needs to be addressed.

 

[don_resqcapt19]

How about this,

"Exception: Unbroken lengths of raceway, without any bends, installed between two fixed enclosures, measuring 36" or less, shall be permitted to be supported by their conduit terminations."

I don't see a need to prohibit bends.