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#96761 - 12/24/05 09:58 AM MC in wet locations
gfretwell Offline


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Registered: 07/20/04
Posts: 9039
Loc: Estero,Fl,usa
Most MC I see is listed "wet location" but do they make a wet location connector?
How do you keep the water out of the box?
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#96762 - 12/24/05 10:40 AM Re: MC in wet locations
George Little Offline
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Registered: 01/18/04
Posts: 1488
Loc: Michigan USA
Can't keep it out. Best advice I'd give would be to provide a drain hole. Something like we have for signs. See 600.9(D) for size for signs. Probably wouldn't need to be that large diameter for boxes but the concept is the same. If one installs the MC cable with a drip loop this would help. Also look at 225.22 and Exception. Interesting.
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#96763 - 12/24/05 11:01 AM Re: MC in wet locations
iwire Offline
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Registered: 01/05/03
Posts: 4391
Loc: North Attleboro, MA USA
The only MC I have installed in wet locations is what we call 'parking deck cable' which is jacketed MC. There area WP connectors for it.

As for standard MC I think George is onto it.

Quote:
348.12 Uses Not Permitted.
FMC shall not be used in the following:
(1) In wet locations unless the conductors are approved for the specific conditions and the installation is such that liquid is not likely to enter raceways or enclosures to which the conduit is connected


It goes without saying MC is not FMC but I think we could apply the same logic.
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Bob Badger
Construction & Maintenance Electrician
Massachusetts
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#96764 - 12/24/05 10:48 PM Re: MC in wet locations
gfretwell Offline


Member
Registered: 07/20/04
Posts: 9039
Loc: Estero,Fl,usa
There just seems to be a disconnect between the people who insist that EMT connectors are raintight and the guy who thinks MC or FMC is OK.
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#96765 - 12/25/05 09:01 AM Re: MC in wet locations
renosteinke Offline
Cat Servant
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Registered: 01/22/05
Posts: 5316
Loc: Blue Collar Country
I was also surprised to learn that MC is approved for wet locations; all the connectors I've seen are marked "dry only."
I also note that a similar product- AC - is NOT approved for wet locations.

I am guessing that the insulated full-size groound, and the plastic (rather than paper) wrap of the wires are the reasons for this approval.

I am also guessing that the intent is to allow MC to pass through a wet location, without requiring a change in wiring methods.
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#96766 - 12/26/05 08:03 AM Re: MC in wet locations
iwire Offline
Moderator
Registered: 01/05/03
Posts: 4391
Loc: North Attleboro, MA USA
Quote:
There just seems to be a disconnect between the people who insist that EMT connectors are rain tight and the guy who thinks MC or FMC is OK.


Good point.
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Bob Badger
Construction & Maintenance Electrician
Massachusetts
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#96767 - 01/01/06 12:02 PM Re: MC in wet locations
tdhorne Offline
Member
Registered: 03/22/01
Posts: 345
Loc: Maryland, USA
Quote:
There just seems to be a disconnect between the people who insist that EMT connectors are rain tight and the guy who thinks MC or FMC is OK.
Did you mean to say
Quote:
There just seems to be a disconnect between the people who insist that EMT connectors should be listed as rain tight and the guy who thinks MC or FMC is OK.

--
Tom Horne

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

"This alternating current stuff is just a fad. It is much too dangerous for general use" Thomas Alva Edison
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#96768 - 01/01/06 08:11 PM Re: MC in wet locations
BobH Offline
Member
Registered: 10/16/04
Posts: 135
Loc: Newfane, N.Y USA
I've seen it strung from a house to a garage and I thought for sure this was a violation when I first saw it, then I checked its listing, I was wrong. It's raintight and I can see a few scenarios where this would be very convenient.
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#96769 - 01/02/06 10:17 AM Re: MC in wet locations
elektrikguy Offline
Member
Registered: 05/25/02
Posts: 132
Loc: woodstock,ga,usa
Interesting timing on this thread....I just finished wiring an exhaust fan for a dishwasher in a commercial kitchen. It was the type with the 1/2 inch tube for the wire to drop through and was roof mounted. The duct guy promptly told me that I needed to install sealtite and a pitch box. He said he has never seen MC used in his career I peeled back the aluminum armor and exposed the THHN-THWN conductors to him.
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#96770 - 01/02/06 11:06 AM Re: MC in wet locations
iwire Offline
Moderator
Registered: 01/05/03
Posts: 4391
Loc: North Attleboro, MA USA
We always use MC for that application.
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Bob Badger
Construction & Maintenance Electrician
Massachusetts
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