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)
234,735 Are you busy
169,494 Re: Forum
162,784 Need opinion
Who's Online Now
0 registered members (), 78 guests, and 11 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
Page 1 of 2 1 2
#87388 - 02/26/04 05:12 PM MC/BX  
SteveMc  Offline
Member
Joined: Feb 2004
Posts: 62
Rock Hill, SC
Is there a difference or just different names for the same thing? If so, then when did the name change occur? Just curious.


2017 / 2014 NEC & Related Books and Study Guides

#87389 - 02/26/04 07:12 PM Re: MC/BX  
Jim M  Offline
Member
Joined: Aug 2001
Posts: 457
Chestertown, MD, USA
Although they look similar the MC cable will have a insulated ground wire, the AC or BX as commonly called relies on the metal jacket and the bond wire.

Red heads or anti-short bushing are required with AC but not MC.


#87390 - 02/27/04 07:24 AM Re: MC/BX  
gunther  Offline
Member
Joined: Sep 2003
Posts: 60
I had never heard that anti-shorts weren't required with MC. They always come with the rolls of MC from the manufacturers that we get and I know they are required in this area. (Digging out code book)


#87391 - 02/27/04 11:11 AM Re: MC/BX  
SteveMc  Offline
Member
Joined: Feb 2004
Posts: 62
Rock Hill, SC
Thanks, Jim, for the quick reply. It settled an argument. As for red heads, that's an ongoing discussion in another forum as well. I use them simply because it's not a lot of trouble and I had a cable blow up in my face once because it was nicked and didn't have a red head. Whoever installed it probably didn't use a Roto-splitter.


#87392 - 02/27/04 12:02 PM Re: MC/BX  
Thom  Offline
Member
Joined: Aug 2002
Posts: 24
Westfield
I also use the red heads but I do believe it is not a code requirement until about 10 AWG. 12 and 14 AWG I don't think you have to.


#87393 - 02/28/04 09:24 AM Re: MC/BX  
Reel-Break  Offline
Member
Joined: Apr 2002
Posts: 178
nc
Here`s a link to anti shorts not required.How ever I still think small price to pay for no returns.We use them.
http://www.nema.org/DocUploads//8B117E35-EFF9-4B09-B6E4722E1E6DFEF3/BULL90.pdf


#87394 - 02/29/04 02:54 PM Re: MC/BX  
electure  Offline


Member
Joined: Dec 2000
Posts: 4,259
Fullerton, CA USA
Good Job, Reel-Break!
I've been looking for something like this for a long time.
I've checked UL, not required.
I contacted AFC and AlFlex both about this; the answer was the same.

"The bushings, though not required, are supplied as an additional means of protection"

Good enough for me...I use 'em.

BX is AC Cable= Bushings always required
MC is MC Cable=Not required, but supplied for free.
You guys make your own decisions as to the value of your time.


#87395 - 03/04/04 02:19 PM Re: MC/BX  
Anonymous
Unregistered

When I started in the trade BX was not used and AC-MC was not yet on the market.
I have been "told" that BX casing can not be used for a ground and the fittings are not rated for grounding. As in retrofitting a ground pigtail in the back of a metal box to change old two wire receptacles to grounding type receptacles using the metal case as a grounding means....Any thoughts?


#87396 - 03/04/04 04:43 PM Re: MC/BX  
tdhorne  Offline
Member
Joined: Mar 2001
Posts: 345
Maryland, USA
Quote
When I started in the trade BX was not used and AC-MC was not yet on the market.
I have been "told" that BX casing can not be used for a ground and the fittings are not rated for grounding. As in retrofitting a ground pigtail in the back of a metal box to change old two wire receptacles to grounding type receptacles using the metal case as a grounding means....Any thoughts?


If the cable in question does not have a bonding strip to insure the continuity of the spiral wound interlocking cable armor you cannot use the armor as an Equipment Grounding Conductor.
--
Tom H


Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous for general use" Thomas Alva Edison

#87397 - 03/04/04 05:26 PM Re: MC/BX  
Anonymous
Unregistered

Thanks Tom,
So then wouldn't "BX" be considered the non grounded armored cable made until some time in the 60's? early 70's? And, was it no longer recognized by the NEC because of the grounding issue? I don't remember seeing AC cable until some time 80's. I know that armored cable disappeared for years and if it was a grounding issue I wonder why they didn't just put a full size ground conductor in it and keep it on the market.


Page 1 of 2 1 2

Member Spotlight
Samurai
Samurai
Fl.
Posts: 46
Joined: May 2007
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: 0.015s Queries: 15 (0.003s) Memory: 0.8138 MB (Peak: 0.9903 MB) Zlib enabled. Server Time: 2017-04-26 17:36:28 UTC