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path1's avatar
path1
Explorer
Jul 08, 2014

Help with wire size and type

(Don't know much about elec here). Couple years ago I started re- wiring a small class C. Any wire that looked bad (corroded, green, etc) was replaced with bigger wire and a new connection. Pretty hard to mess up going wire by wire and a camera taking pic's IMO. Fast forward couple years and I need to finish this project. I have some wire that I don't know if I can use in rv or not. I'm under the opinion if it conducts elec and bigger than old wiring it will be good to go. I didn't like paying for the new wire, was surprised how much it costs.

I have 127 feet of

(markings on cord in ink ) 8/4 type so 90degree C F-123 70 MSHA

(stamped into cord) P-123-MSHA

Is this stuff good enough to replace wiring? I won't use this stuff for any wire that is bigger such as battery cables, but for wire less size in diameter will this stuff work? I know it is heavy duty especially if your lifting it. Bet it weighs 40 pounds.

(Got this stuff because the campground lot at wanted to move us because the old elec went out (20 amp to each lot back then). They wanted to exchange for on of there unsalable cheap tiny junk lots. Permanently. One for one trade. No way!!! I picked up this wire at a business that tears down old commercial buildings. Think I paid $75.00 twenty years ago. I ran the wire in back of our lot to a friends lot and paid his elec until our section got elec re-built. Which took 2 years because of $$$. When we could use our "own" new elec again I stuffed the wire in front of 5th wheel compartment, and it's been there ever since, so trying to use it.)
  • path1 wrote:
    Thanks to all that replied...

    Where would you think would be the best place to sell the wire at???
    Put it up on CL.
    What are you wiring? I may be able to help you out.
  • Thanks to all that replied...

    Where would you think would be the best place to sell the wire at???
  • I would sell the 8/4 SO and buy what is right for the job. That SO should sell for several hundred dollars, enough to get what is called for.
  • That wire is not really suitable for much of anything in an RV. It's too big for most of the general circuits and too small for battery connections.
    Take it in for recycling - you'll be surprised how much you get.
  • That is 8g wire with 4 wires included, black, white, red and green (or bare). Note that 8g wire is good to about 55 amps with 90 degree C insulation.

    It is sometimes called 8/3 w/g (8g, 3 wires, plus a ground wire).
  • path1 wrote:
    8/4 type so 90degree C F-123 70 MSHA



    8/4...8 gauge 4 wires [black, white, green, red]

    SO....S=appliance cord stranded conductors cotton layer between wire and insulation jute fillers rubber outer jacket [individual wire insulation] extra hard service. O=neoprene jacket [outer insulation]

    90C...maximum working temperature[hot] before insulation failure.

    F-123-70.....manufacturer identification/part number

    MSHA......Mine Safety and Health Administration

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