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Joined: Mar 2003
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600 volt three conductor (310.20??), or 4160 three conductor(310.73??) either with messager.
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Joined: Jul 2004
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If the 3 conductors are in a metal jacket I don't think any "free air" table applies (one opinion).


Greg Fretwell
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IMO: Not only do you use the 'standard' table (310.16), but you might even have to derate for heat (in the sun), as you wpould were they over a rooftop.

I believe the 2008 also would require this MC to be in a waterproof jacket as well.

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310.73 MV : In Isolated CONDUIT in air. So that one I;m pretty sure of.
310.18 LV : Not sure of?

Joined: Nov 2007
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K
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For the 600V, I think you may need to use Table B.310.3 in Annex B, since it specifically mentions type MC cable in free air.
For over 2000V though, with three conductors, I believe you could use table 310.71, since IMO, the MC jacket is not actually a conduit or raceway as defined in Art.100.

Joined: Nov 2007
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K
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I probably should have said you may want to use Table B.310.3 in Annex B.

Joined: Jul 2007
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Just carious, why are you stringing MC on a messager? Or am just interpting something wrong here?


"Live Awesome!" - Kevin Carosa
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MC cable on Industrial sites is quite often put on poles to remote pumping stations ect. Both 600v & i;ve even see 15kv in MC on poles.
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I have never seen it before either, which tends to explain my silly answer above, sorry for the confusion. wink


Greg Fretwell
Joined: Mar 2003
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mc cable 330.10 (B)4.

Installed outside of buildings or structures or as aerial cable.
type mc cable installed outside of buildings or structures or as aerial cable shall comply with 225.10,396.10,& 396.12.

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