50 Amp RV Receptacle, 100' run

Roaddoggie · 03-08-2011, 07:55 PM

I need to install a 50 amp RV receptacle on the far wall of my shop building. The run will be all inside from a 200 amp panelboard going up 8' in conduit, then a 82' run without conduit on top of a purlin, then 10' down in conduit to the receptacle. I believe that to keep the voltage drop reasonable I can use 6 awg. Keep in mind that a 50 amp RV service uses the two legs as separate 120's and does not use 240. What cable can I use for this? Or do I need to use separate conductors in EMT for the whole run? Thanks

Speedy Petey · 03-08-2011, 08:11 PM

Quote:

Originally Posted by Roaddoggie

Keep in mind that a 50 amp RV service uses the two legs as separate 120's and does not use 240.

Even if there are no 240v loads (which I doubt) it is still a 120/240v circuit.

I would use #6THHN conductors in conduit myself. Two hots, neutral and ground. You can drop to a #10 for the ground.

Roaddoggie · 03-08-2011, 08:48 PM

Actually, you're right, there are supposely some top end buses that use 240, but most RV's don't. I know my diesel pusher doesn't. And what would be cheaper, SER or separate conductors in EMT?

cschwehr · 03-08-2011, 09:03 PM

Quote:

Originally Posted by Roaddoggie

Actually, you're right, there are supposely some top end buses that use 240, but most RV's don't. I know my diesel pusher doesn't. And what would be cheaper, SER or separate conductors in EMT?

Cheaper?

Probably #6 NMD on surface sleeved in conduit as you mention since you can get it cut easily from a wholesaler. The cleanest and "best" would be to have THHN all in conduit... but it's up to you.

Nobody runs 60A hot tub loads with THHN in conduit in practice, but in a large shop where you are moving things and using tools I would like to protect it everywhere, if you're covering it in wall with drywall, it could be NMD with probe plates and as long as the run is high, it would meet code in my area.

cschwehr · 03-08-2011, 09:05 PM

Quote:

Originally Posted by cschwehr

Probably #6 NMD on surface sleeved in conduit

I mean sleeved in PVC till you get above 8'... Not the whole run.

Tigerloose · 03-08-2011, 09:15 PM

#6 thwn

cschwehr · 03-08-2011, 09:19 PM

Quote:

Originally Posted by Tigerloose

#6 thwn

Why? It's all indoor, he doesn't require a wet location rated cable...

Speedy Petey · 03-08-2011, 10:10 PM

Quote:

Originally Posted by cschwehr

Why? It's all indoor, he doesn't require a wet location rated cable...

THWN is a conductor, not a cable. And when was the lat time you got THHN that was not dual rated with THWN?

cschwehr · 03-08-2011, 11:43 PM

Quote:

Originally Posted by Speedy Petey

THWN is a conductor, not a cable. And when was the lat time you got THHN that was not dual rated with THWN?

One minute you're making sure sure I'm correct on my terminology and the next you're telling me that it's always dual rated - you're correct on both topics though... Thanks for ensuring my initial posts are slowly typed in the future or not typed at all.

Speedy Petey · 03-09-2011, 05:28 AM

Quote:

Originally Posted by cschwehr

Thanks for ensuring my initial posts are slowly typed in the future or not typed at all.

Hey, no problem.