ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
A 5-20(20a) receptacle is legal on a 15a circuit?
by libellis - 10/10/21 12:46 PM
GFCI's pops in large numbers
by dsk - 10/07/21 03:46 PM
Backup Generator Done Right
by timmp - 10/06/21 02:07 PM
How's all our Non-US folks doing?
by dsk - 09/30/21 05:06 AM
Well I am back to stay (nearly 6 years)
by Bill Addiss - 09/26/21 11:09 PM
New in the Gallery:
240/208 to a house
240/208 to a house
by wa2ise, October 9
Now you know.
Now you know.
by Tom_Horne, September 7
Who's Online Now
1 members (Scott35), 10 guests, and 23 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Joined: Jun 2012
Posts: 75
Member
Hello- I have a question about installing mc cable under a patio or porch that is 12 x 12 open wall.

I say damp location.

Are stamped octagon boxes and screw type connectors allowed?

Thank you


Don't drive and TEXT! Drive now TALK LATER!
2017 / 2014 NEC & Related Books and Study Guides
Joined: Jul 2004
Posts: 9,667
Likes: 5
G
Member
If it is a rain tight deck, (no water feeds through the cracks) it may be damp but I would still use bell boxes. Those galvanized octagon boxes will still rust up pretty bad in a damp location. I am not sure how they are listed because few people even try it here.


Greg Fretwell
Joined: Apr 2002
Posts: 7,282
Likes: 3
Member
Although the Code allows MC, I will go along with where Greg is going regarding the patio/deck being rain tight.

Are you talking alum jacket MC, or steel jacket? Personally I would have an issue with alum jacket being 'outside'. Note I say 'personally'. Or are you talking PVC jacketed MC which would be no issues, with the listed connectors, and a suitable box for the enviornment.

Maybe PVC conduit and PVC device boxes would be a better choice?



John
Joined: Jul 2004
Posts: 9,667
Likes: 5
G
Member
There was a while when aluminum MC cable was sold as wet location. I am not sure why it was OK and then why it wasn't.

[Linked Image from gfretwell.com]


Greg Fretwell
Joined: Jul 2004
Posts: 9,667
Likes: 5
G
Member
I like RNC but it does have that sagging problem in the summer unless you strap it every 2 feet or so and you also need to deal with expansion issues.


Greg Fretwell
Joined: Apr 2002
Posts: 7,282
Likes: 3
Member
Greg:

I take that label as the rating/listing for the conductors, not the jacket, unless I'm missing something here.

I have seen the al jacket corroding in a few unfinished (older) basements that had no cliamate control.


John

Link Copied to Clipboard
Featured:

Tools for Electricians
Tools for Electricians
 

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
timmp
timmp
Leo, IN, USA
Posts: 28
Joined: June 2004
Top Posters(30 Days)
dsk 5
Popular Topics(Views)
284,589 Are you busy
217,288 Re: Forum
203,646 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5