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Joined: Jul 2004
Posts: 9,928 Likes: 34
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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?
Greg Fretwell
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Joined: Jan 2004
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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.
George Little
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Joined: Jan 2003
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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. 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.
Bob Badger Construction & Maintenance Electrician Massachusetts
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Joined: Jul 2004
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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.
Greg Fretwell
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Joined: Jan 2005
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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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Joined: Jan 2003
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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.
Bob Badger Construction & Maintenance Electrician Massachusetts
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Joined: Mar 2001
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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 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
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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Joined: Oct 2004
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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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Joined: May 2002
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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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Joined: Jan 2003
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We always use MC for that application.
Bob Badger Construction & Maintenance Electrician Massachusetts
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Posts: 44
Joined: July 2013
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