what type of wire for 120v

[Lunchbox7985]

I did a little searching but didn't turn up any solid answers. I plan on having 2 circuits, both 15 amp. Going to havea microwave and a couple outlets on one, and a mini fridge and a couple more outlets on the other. Going with a 12 gauge 25 foot extension cord for shore power, and 12 gauge wire from the shore outlet to the breaker box. (Probably like 2 feet) . Then planning on 14 gauge wire to run to the outlets (a 15 foot run, and a 5 foot run) at most I may wire a light to a switch, adding another 4 to 5 feet to the 5 foot run.

first question are my gauges kosher?

Then what type of wire do I use? I see this NM and THHN. I'm confused. I'm using treated lumber if that changes anything. Do i need conduit? I'm not insulating my trailer at all. And I dont know how much I'm going to seal it past the wood screwed down. So it may see moisture in the air.

[citylights]

See link. 14 gauge is good for the 15 amp circuits, maybe 10 gauge for the main service. Also all wire should be woven strand, not solid.

http://www.tnttt.com/viewtopic.php?f=30&t=11316

[bobhenry]

I personally would stay with 12 gage for any outlet where you may be plugging in a heating appliance. ie toaster oven , Microwave, coffee pot, electric hot plate. The 14 gage is fine for lighting circuits.

I have built with 12 gage 3 wire extention cord single strand 12 gage wolven wire and 12 gage romex solid core wire. I feel as long as the gage will handle the load the wire type is a mute point.

[les45]

+1 on what bobhenry said; I wired all my AC system with 12 ga romex (solid strand) with no problems. I have a 20 amp inlet and a 12 ga extension cord for connecting to campground service. I use space heater, coffee pot, electric griddle, and microwave (just not all at the same time). Don't forget a GFCI somewhere upstream of the outlets.

[Lunchbox7985]

i should add incase you havent read my other posts, this is just a little chuck wagon, so microwave, fridge, sink pump, and light, is probably gonna be it. i plan on making coffee with propane.

[Lunchbox7985]

but aside from size, what type of wire do i need to use?

[bobhenry]

Most circuits in the modern North American home and light commercial construction are wired with non-metallic sheathed (NM) cable designated type (often referred to by the brand name "Romex.This type of cable is the least expensive for a given size and is appropriate for dry indoor applications.


THWN stands for "Thermoplastic Heat and Water-resistant Nylon-coated

THWN is a designation for a specific insulation material, temperature rating, and condition of use (wet locations) for electrical wire and cable


THHN stands for "Thermoplastic High Heat-resistant Nylon-coated."

THHN is a designation for a specific insulation material, temperature rating, and condition of use (suitable for dry and damp locations) for electrical wire and cable.

Is that what you want to know

[asianflava]

You probably want 4-6ft for your shore power plug. If you plan on using an extension cord every time, you may as use this:

[les45]

but aside from size, what type of wire do i need to use?

ROMEX; regular old house wire

[Lunchbox7985]

thanks bob and les, so regualr old romex wire is fine in direct contact with treated lumber, and in a slightly less than perfectly sealed wall that will be outside?

[Engineer Guy]

Good ole solid Romex will be fine. 14 AWG 15 Amp Romex has a white sheath. Both my older commercial Trailers are wired with it. 20 Amp [which you don't need] has a yellow sheath. I wired my new House myself to Code, so I re-learned whatever details I forgot as a Kid. At any Big Box Store, you'll likely find the other 2' scrap Wire piece you need in a Remnants Barrel.

There are U-shaped Romex Staples that are just Steel. There are others that have some black Insulation-looking material around the center of the Staple. It provides some cushioning effect, and doesn't wind up putting raw Steel against the Romex. Consider using those.

In any case, the Newbie error to avoid is to not hammer the U Staple down 'too far'. There's no need to squash the Romex. Just tap the U Staple down enough to avoid Romex movement and call it a day. I hold the U Staples in place with my Long Nose Pliers because I got tired of hitting my Fingers with a Hammer.

[Socal Tom]

I used a 14ga extension cord and cut it up. That gave me the 3 wire flexible stuff with a waterproof covering.
Tom