Should I use marine 3 wire cable or seperate wires for 110V AC?

[Beatenbo]

My last three buses I used the flat gray stuff you buy at Home Depot that is made for direct sunlight or burial. I have never had a any problem and it has a much more durable jacket than the regular romex. It's only a few bucks higher and works fast. I bought a 250 ft roll of 12ga for 3 AC, micro, water heater, toekick ect. The 14 ga is much easier to work with and will handle 15 amps for TVs land other small stuff. I have seen a lot of motorhomes that had plain old romex from the factory.

[zxt]

Brian,
     This question has been discussed many times before.  And generated considerable controversy. To summarise:  The marine cable is NOT approved, under the National Electrical Code (NEC), for use in an RV.  While it may in fact be more suitable it is NOT approved.  Solid wire 'romex' is approved as is stranded 'thnn' in conduit.  ...........................
Regards
Jerry 4107 1120   

What is 'thnn' wire? My code book doesn't seem to list that.
Not even in Article 551 for RV's.

[gumpy]

Jerry, all of my wiring is stranded and all of it is wrapped around the terminal screws at all outlets and switches! Is this wrong?

Ace

Ace,

While I'm neutral on the subject of stranded thhn in conduit vs. solid romex and tinned boat wire (I believe they are all safe if installed properly), I have to go with Jerry on this one. Wrapping stranded wire around the switch and outlet screws is just not safe. There is just too much risk of the connections becomming loose or the strands breaking due to vibration or overtightening of the screws.

I highly recommend you go to waytekwire.com and order a bunch of crimp on fork terminals (I'd recommend ring terminals, but often the screws in switches and outlets are designed so they won't come out of the holes) and a good quality crimper such as their number 434.  http://order.waytekwire.com/IMAGES/M37/catalog/218_027.PDF  At $131 it's not cheap, but it's the best money I've spent on bus related tools, so far.

While you're there, get yourself a good stripper (no, not that kind) such as their item 444. Again, money well spent in terms of quality of the end product and time spent.  

They also offer some clear plastic shrink tube which can be used to attach paper labels to your wires while insulating crimped terminal ends.

craig

[gumpy]

What is 'thnn' wire? My code book doesn't seem to list that.
Not even in Article 551 for RV's.

It's a misprint.  He meant THHN.  There's also TFFN which is basically the same thing, but in smaller gauge wire.

[Jerry Liebler]

Thank you Craig.  I mistyped THHN and didn't catch it  Again boat wire can be safe even though it is not approved for use in an rv, by the NEC.  Without proper connections though stranded wire is a definite saftey issue. 
Regards
Jerry 4107 1120. 

[belfert]

Thank you Craig.  I mistyped THHN and didn't catch it  Again boat wire can be safe even though it is not approved for use in an rv, by the NEC.  Without proper connections though stranded wire is a definite saftey issue. 

I thought the NEC had ceded control over RVs to the NFPA or the RVIA?

The RVIA codes are bare minimums that make sure the RV is cheap the manufactur and make it past the warranty period.  (Might be a bit of an exaggeration.)

Brian Elfert