ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Top Posters(30 Days)
Potseal 11
Recent Posts
Why cables look like they do
by LongRunner. 04/26/17 09:36 AM
Dimmable LED 2x4 lay in fixtures
by HotLine1. 04/24/17 05:43 PM
Old decora style outlets
by Lostazhell. 04/22/17 07:59 PM
Permit Snafus...AHJs and Contractors Jump in
by gfretwell. 04/22/17 01:11 PM
How do you find a good employee?
by HotLine1. 04/22/17 10:44 AM
New in the Gallery:
SE cable question
Popular Topics(Views)
234,727 Are you busy
169,482 Re: Forum
162,774 Need opinion
Who's Online Now
1 registered members (LongRunner), 78 guests, and 11 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
Page 1 of 5 1 2 3 4 5
#215109 - 03/04/15 08:44 PM "Forbidden" Fittings?  
renosteinke  Offline
Cat Servant
Member
Joined: Jan 2005
Posts: 5,316
Blue Collar Country
I figure it's time we had a thread to specifically address the use of fittings that accomplish, as best I can tell, things you're not allowed to do.

Now, it's possible that my understanding of the NEC is flawed. After all, all of the fittings I intend to bring up are UL listed- and UL, as a matter of policy, will NOT list something for which there is no code-compliant use.

Today's fitting is a new one, proudly introduced by Bridgeport Fittings. The fitting is intended to allow for the direct connection of MC to EMT. Look at it here: http://www.bptfittings.com/Home/ProductDetail?id=00781747944562

Now, the existence of this fitting brings up any number of tangents ... but I'd like to limit our discussion to one: namely, is there EVER a circumstance where you can use this fitting?

Some might say "sure- I can eliminate a box and just extend the MC wires back into the pipe, as far as I need to go, until I get to a box I really need."

The problem is- and feel free to correct me here- I think the NEC requires the wires to be marked with insulation type, etc. .... and NO ONE makes MC with marked wires.

What do you think?


2017 / 2014 NEC & Related Books and Study Guides

#215112 - 03/05/15 01:01 AM Re: "Forbidden" Fittings? [Re: renosteinke]  
HotLine1  Offline


Member
Joined: Apr 2002
Posts: 6,809
Brick, NJ USA
Common acceptable practice is the use of 'from-to' fittings to eliminate the need for a box. Over the many years I have been in the trade, I have seen, used, made up many a transition from cable to raceway, etc.

To get to the core of your topic, the markings on conductors IMHO in a situation would not raise a question.

I seem to remember seeing markings on some #12 or 10 MC. It was stranded for sure. I'll reach out for the EC who is on that job to check. I'm not disputing what you say Reno, I just feel it is something that just gets by without ????




John

#215122 - 03/05/15 02:02 PM Re: "Forbidden" Fittings? [Re: renosteinke]  
gfretwell  Offline


Member
Joined: Jul 2004
Posts: 9,069
Estero,Fl,usa
I agree if you extended the conductors from MC cable through the EMT it is a technical violation. I also think that, presented with it, I would say it was better than another splice.
There should be marking on the MC cable that will suffice to tell me what the conductors are.

If this is FMC that they are using, no foul at all.
You should be pulling a marked discrete conductor anyway.

Since you don't have a firmly mounted box it will make strapping that EMT termination more important. (assuming you are transitioning to a whip)


Greg Fretwell

#215125 - 03/05/15 11:33 PM Re: "Forbidden" Fittings? [Re: renosteinke]  
Tesla  Offline
Member
Joined: Jun 2004
Posts: 1,273
Sacramento, CA
The only thing missing is the markings...

But, since they erupt from a listed cable assembly -- MC -- and the EMT is even more protection than the aluminum 'tape' used by the MC...

I don't see a problem.

I've never heard "boo" about it from any inspector.

Now, obviously, if the MC was internally marked you'd be satisfied...

Of course, the wire used is THHN or better. These days THWN-2 is the norm.

It's required by the standards of the MC -- which is pitched as being able to handle generally wet conditions -- but not submerged conditions. (There's PVC coated MC for that.)


Tesla

#215126 - 03/06/15 01:25 AM Re: "Forbidden" Fittings? [Re: renosteinke]  
electure  Offline


Member
Joined: Dec 2000
Posts: 4,259
Fullerton, CA USA

They said the "Use of Antishort bushings is required on AC/MC" too.

AC yes, MC no.


#215127 - 03/06/15 01:53 AM Re: "Forbidden" Fittings? [Re: renosteinke]  
gfretwell  Offline


Member
Joined: Jul 2004
Posts: 9,069
Estero,Fl,usa
There are still guys who want to see the bushing on MC but I agree it is usually not necessary.
OTOH if this connector actually says you need bushings in the instructions it is a 110.3(B).

I am still trying to think of where I would use this fitting.



Greg Fretwell

#215128 - 03/06/15 05:13 AM Re: "Forbidden" Fittings? [Re: renosteinke]  
Tesla  Offline
Member
Joined: Jun 2004
Posts: 1,273
Sacramento, CA
Scott,

In Sacramento County, the AHJ DOES insist on red hats for MC.

BTW, the various listed fittings ALWAYS have a port so that - said red hat can be viewed.

&&&&

The reality that red hats are not needed everywhere has caused the trade to ship MC coils with either no anti-short bushings at all -- or just a teaser baggie -- with just enough red hats to be suggestive.

Inserting the red hats is such an insignificant labor burden that I pay the issue no heed.

Hereabouts, no-one ever uses AC -- except where mandated. (Hospitals, for the most part.)

&&&&&&&&&&&

For those wondering why AC instead of MC -- AC has a MUCH heavier 'tape' wrapped around it... and always did.

THAT'S the original, primary, reason why it was spec'd.

Then, as time went by, and low voltage electric devices became universal in hospitals, the redundancy of a belt and suspenders approach was deemed THE way to go.

Lest anyone forget, half of these gadgets are hooked indirectly into the blood stream! This makes the patient part of the equipotential ground plane.

So, hospital grade AC became endowed with additional grounding conductors.

Even with additional grounding conductors, MC tape is simply not deemed enough protection against physical abuse -- which you should read to mean: earthquakes and nuclear blasts.



Tesla

#215129 - 03/06/15 11:58 AM Re: "Forbidden" Fittings? [Re: Tesla]  
electure  Offline


Member
Joined: Dec 2000
Posts: 4,259
Fullerton, CA USA
Originally Posted by Tesla
Scott,

In Sacramento County, the AHJ DOES insist on red hats for MC.


http://www.southwire.com/commercial/nema-bulletin-90.htm

All of California is on basically the 2011 NEC, with CA Energy Code Amendments (2013 CEC)
They are only allowed to add their own local amendments to Building Codes under certain very limited conditions (seismic, climatic, etc)

I'd be willing to bet that the requirement isn't written down anywhere.

I personally use them even though they aren't required


#215133 - 03/07/15 08:08 PM Re: "Forbidden" Fittings? [Re: renosteinke]  
HotLine1  Offline


Member
Joined: Apr 2002
Posts: 6,809
Brick, NJ USA
I see about 60-70% of MC installs with red heads. I guess IF the MC comes with the red heads, why not use them.

Back to Reno's fitting.......


John

#215135 - 03/08/15 01:09 PM Re: "Forbidden" Fittings? [Re: renosteinke]  
renosteinke  Offline
Cat Servant
Member
Joined: Jan 2005
Posts: 5,316
Blue Collar Country
"Red heads" are, strictly speaking, outside the range of this thread. After all, there's no rule AGAINST using them.

By contrast, let's look at this clip made by Caddy:
http://www.erico.com/category.asp?category=R1106

This fitting is one of many that are designed specifically to attach conduit and boxes to suspended ceiling grids. I've seen installations that used these clips, so it's possible that they were allowed at some time.

Today, though, I can see no situation where the NEC allows anything to be supported by any suspended ceiling.

I don't buy the "for positioning only" disclaimer.

What about the lack of a UL listing? As best I can tell, supports are not required to be listed. Caddy lists its' "minerallac" style hanger, but not the one-hole straps. As best I can see, code allows you to hang pipe using rubber bands, shoe laces, and bubble-gum ... as long as you're not hanging it from the ceiling grid!

IS there any 'legal' use for these t-bar fittings?


Page 1 of 5 1 2 3 4 5

Member Spotlight
Vlado
Vlado
Croatia
Posts: 28
Joined: February 2011
Show All Member Profiles 
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.018s Queries: 16 (0.003s) Memory: 0.8283 MB (Peak: 1.0074 MB) Zlib enabled. Server Time: 2017-04-26 13:51:32 UTC