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That One Guy

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I bought a 35 foot 5th wheel a couple of days ago, and last night I went to plug it in so I can keep the batteries charged up. There is a little problem though:

The plug is a 125/240 50A 4/6 SO wire. 4 Wire 3 pole. I need to bring that down to 125V to plug it into a regular 120V house outlet. Does anyone know how to wire it?

I bought a 4 prong (three blade and round ground) female plug to plug the cord of the 5th wheel into, but I'm not quite certain on how to wire it. Best I can figure is Green for ground, black goes on the right blade, and white goes on the left one, leaving the bottom blade empty. I'm getting power to the Microwave and 1/2 the plugs in the camper (as well as the ceiling fan), but the batteries aren't charging. I checked fuses, and nothing is popped. I know the charger and the rest of the plugs work when plugged into a 240/50A socket.

Did I wire that thing correctly?

I'd ask an electrician friend of mine, but he's out hunting, and his cell phone is turned off... go figure.

Thanks guys.
 
That One Guy said:
I bought a 35 foot 5th wheel a couple of days ago, and last night I went to plug it in so I can keep the batteries charged up. There is a little problem though:

The plug is a 125/240 50A 4/6 SO wire. 4 Wire 3 pole. I need to bring that down to 125V to plug it into a regular 120V house outlet. Does anyone know how to wire it?

I bought a 4 prong (three blade and round ground) female plug to plug the cord of the 5th wheel into, but I'm not quite certain on how to wire it. Best I can figure is Green for ground, black goes on the right blade, and white goes on the left one, leaving the bottom blade empty. I'm getting power to the Microwave and 1/2 the plugs in the camper (as well as the ceiling fan), but the batteries aren't charging. I checked fuses, and nothing is popped. I know the charger and the rest of the plugs work when plugged into a 240/50A socket.

Did I wire that thing correctly?

I'd ask an electrician friend of mine, but he's out hunting, and his cell phone is turned off... go figure.

Thanks guys.
Click to expand...

If you have a 4 wire 3 pole setup it's likely 240V like your electric range, dryer or furnace. You need 2 phase power. You should have green for ground and red, black and white. White will be neutral and the black and red will be the two separate 120V phases. The neutral lug should be a silver/chrome color compared to the others which are copper/brass colored. Measuring with a voltmeter, you should get 240V phase to phase and 120V phase to neutral. The way you have it wired now is you are missing a phase. As you found out, half your stuff is not working.

You really need to get an electrician to install an receptacle box for you to be able to plug into. It should be on a separate 50A 2 pole breaker, preferably ground fault protected since it will be feeding a cable outside. You could temporarily wire in a pigtail from your main with a length of SO, but you wouldn't want your insurance company to know since it wouldn't be up to code.

No, I'm NOT an electrician, but I did stay at Holiday Inn Express. LOL :)
 
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Driller:

That's what I came up with after searching the net for a while.

But since I don't really need 240/50A shore power to just keep the batteries charged, I only used the black wire on one pole. It works great. No AC or microwave, but I have fridge and battery recharging.

Thank you though.
 
Congrats on the purchase. I have a '42 Motorhome -- I think what you want(ed) is a "dogbone" adapter that takes it from 50 to 15A or if you can't find one, 50->30->15. Before I had 100A (50/30/20) installed to the pad, I used that and an extension cord to keep the batteries charged and fridge cold.
 
LLT said:
Congrats on the purchase. I have a '42 Motorhome -- I think what you want(ed) is a "dogbone" adapter that takes it from 50 to 15A or if you can't find one, 50->30->15. Before I had 100A (50/30/20) installed to the pad, I used that and an extension cord to keep the batteries charged and fridge cold.
Click to expand...

WOW! That 1942 motorhome sure has held up well!!! What brand is it!!! :D
 
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