How do I wire a 15amp to 50 amp adapter cord?

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lesd

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Jan 19, 2010
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I am interested in wiring up a short adapter cord to allow me to run minimal systems on regular
home power. Is there a guide for how this should be wired up? The plug side of the HM cable has poles, one of which is round.
Does the 115V 15 amp side get wired to both phases of the MH side ?
 
lesd said:
I am interested in wiring up a short adapter cord to allow me to run minimal systems on regular
home power. Is there a guide for how this should be wired up? The plug side of the HM cable has poles, one of which is round.
Does the 115V 15 amp side get wired to both phases of the MH side ?
Click to expand...

My recommendation is to do yourself a huge favor and buy the adaptor from a RV store, either online or inperson.  They are really cheap compared to the time you'll spend making one.  Most hardware stores have them as well.  The "trick" is to get a 50amp to 30amp adaptor, then a 30amp to 20amp adaptor.  Sometimes you'll need 50amps, sometimes 30amps and sometimes, like now, 20amps.  This will keep the hot wires going to the right places, etc.
 
Camping World sells the 50A to 30A to 15A adaptors. You have to step down in that order.
 
lesd said:
I am interested in wiring up a short adapter cord to allow me to run minimal systems on regular
home power. Is there a guide for how this should be wired up? The plug side of the HM cable has poles, one of which is round.
Does the 115V 15 amp side get wired to both phases of the MH side ?
Click to expand...
Wiring it up yourself has many advantages and eliminates the need for several adapters.


Color  15a    50a
White  W      W
Black  Hot    Connect to X and Y with a jumper
Green  Ground Ground

Some 50a receptacles may be marked X1 and X2 rather than X and Y.  No matter, connect them the same way.

The W terminal will have a silver-colored screw for identification on both connectors.

The ground terminals will have a green screw for identification.

Use heavy gauge wire, either 12 or 10, and a heavy duty 15A plug that will work with the heavy wire.  Smaller wire, in addition to the obviously lesser current carrying capacity, won't fit securely in the terminals on the 50a receptacle.

Starting out with a heavy-duty 15A extension cord from the home center may be the cheapest way.  If you want a short adapter, they have those 2 foot long ones with a block of 3 outlets on the end.  Buy one of those and cut off the block of 3 outlets.  Otherwise, you can make the cord any length that makes sense for your situation.
 
Once you figure out which way you want to go with sizing down to 15 amps make sure you purchase a 15 amp extention cord if an extension is needed.

FastEagle
 
I am a retired electrician. The OP doesn't sound like he knows anything about electricity. This is a recipe for disaster. You aren't going to learn the finer points of how to make an adapter. If you are the least bit concerned about the problems you are might cause doing this wiring yourself you should think about buying an adapter. Much cheaper in the long run just to buy it.
 
You're going to need a 30A male to 50A female adapter some day when you get to a campground with just 30A service so I recommend you buy it rather than try to make one.  And a 15A male to 30F adapter is inexpensive and compact so buy that too.
 
You can buy them already made up. I have the twist lock 50 amp receptacle. I bought mine on sale from CW. It's about 16" long with the 50 amp twist lock to a male 15 amp plug. You just hook up the appropriate length of 15 amp and you are good to go...

 

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Thanks for all the info guys. I am the OP, and I am very familiar with electronics, just not as familiar with house wiring.
Sure, you can but everything, but I noticed that Home Depot sells the surface mount 50 amp socket for something like $15. Camping world sells the made up cable for four times that, just for half of my needs. Anyhow, I bought a 30 to 50 amp on e-bay for 27 shipped, and I'll make the 15 to 30 out of parts I already have.
I hope that will be enough adapters for Mexican camp grounds, and the like.
 
Here is a nice adapter plug for 50 to 20 amp.  See photos.

JerryF
 

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seilerbird said:
I am a retired electrician. The OP doesn't sound like he knows anything about electricity. This is a recipe for disaster. You aren't going to learn the finer points of how to make an adapter. If you are the least bit concerned about the problems you are might cause doing this wiring yourself you should think about buying an adapter. Much cheaper in the long run just to buy it.
Click to expand...

Many people who have a reasonably broad background in matters electrical are confused about what 50 amp service actually means and how it is supposed to be wired.  You and I both know that it's 50A, 240/120V, grounded service, with an NEMA 14-50 connector, that each of the two hot terminals provide, nominally, 50 amps, that nominally there's 240 volts between the two hots, and that there is a full-size neutral.

Some people erroneously believe that one hot terminal is rated for 30 amps and the other is rated for 20 amps for a total of 50.

Some people think it's just like a 30 amp service only with more amps.

I think it's worthwhile to dispel these myths and explain the wiring.  People can decide for themselves whether they're qualified to wire what amounts to a glorified extension cord.

 
Jammer,

On our MH I even have identified all the electrical items, like 120 V outlets, Microwave, battery charging, A/Cs, and so forth so I know which something to shut down down temporally depending upon which 50 amp circuit it is on.  For example, in the front/kitchen area if we are running the electric element for the AquaHot, TV, several lights, the front A/C and we want to use the microwave to warm up something we know to temporally turn off the AquaHot electric element. 

It's also nice to know which 120 volt wall outlet is on which 50 amp circuit because it may make a difference when choosing a wall outlet for a 1600 watt electric floor heater when low batteries are being charged at, let's say, 90 to 100 amps, especially when running the generator.

JerryF
 
taoshum said:
My recommendation is to do yourself a huge favor and buy the adaptor from a RV store, either online or inperson.  They are really cheap compared to the time you'll spend making one.  Most hardware stores have them as well.  The "trick" is to get a 50amp to 30amp adaptor, then a 30amp to 20amp adaptor.  Sometimes you'll need 50amps, sometimes 30amps and sometimes, like now, 20amps.  This will keep the hot wires going to the right places, etc.
Click to expand...

I totally agree..
 
lesd said:
Thanks for all the info guys. I am the OP, and I am very familiar with electronics, just not as familiar with house wiring.
Sure, you can but everything, but I noticed that Home Depot sells the surface mount 50 amp socket for something like $15. Camping world sells the made up cable for four times that, just for half of my needs. Anyhow, I bought a 30 to 50 amp on e-bay for 27 shipped, and I'll make the 15 to 30 out of parts I already have.
I hope that will be enough adapters for Mexican camp grounds, and the like.
Click to expand...

For Mx, I strongly suggest that you take a plug that will allow you to switch the hot side to the "other" side when you plug into a 15/30 amp receptacle.  Of course you'll need to test the receptacle first to either verify that it is wired correctly and you can use the normal plug or that it is wired incorrectly and you'll have to use the reversible plug and a separate ground wire to clip onto a secure ground point.
 
Jammer said:
Wiring it up yourself has many advantages and eliminates the need for several adapters.


Color  15a    50a
White  W      W
Black  Hot    Connect to X and Y with a jumper
Green  Ground Ground

Some 50a receptacles may be marked X1 and X2 rather than X and Y.  No matter, connect them the same way.

Jammer, I am mounting a 50 amp box on my house for a shore line ( got it cheap ) to confirm I just jump the black feed line to X and Y for the circuit to work correctly?

The W terminal will have a silver-colored screw for identification on both connectors.

The ground terminals will have a green screw for identification.

Use heavy gauge wire, either 12 or 10, and a heavy duty 15A plug that will work with the heavy wire.  Smaller wire, in addition to the obviously lesser current carrying capacity, won't fit securely in the terminals on the 50a receptacle.

Starting out with a heavy-duty 15A extension cord from the home center may be the cheapest way.  If you want a short adapter, they have those 2 foot long ones with a block of 3 outlets on the end.  Buy one of those and cut off the block of 3 outlets.  Otherwise, you can make the cord any length that makes sense for your situation.
Click to expand...
 
Jammer
I have a 50 amp box (got it cheap) to wire this to a 20 amp circuit for a shore line I just jump my black feed between X and Y?

Thanks!
 
joe stanley said:
Jammer
I have a 50 amp box (got it cheap) to wire this to a 20 amp circuit for a shore line I just jump my black feed between X and Y?

Thanks!
Click to expand...

Joe don't know if you know it but this post was written 7 years ago.
 
joe stanley said:
Jammer
I have a 50 amp box (got it cheap) to wire this to a 20 amp circuit for a shore line I just jump my black feed between X and Y?

Thanks!
Click to expand...

Yes, but you'll have to be real careful what you turn on at the same time. Remember there are things running in the background (think battery charger for one) that we forget about.
 
15 amp plug has 3 contacts.. The round one gets a GREEN wire, the narrow one should be copper colored and gets a black wire, the wide one is silverish and gets a WHITE wire

On the 50 amp plug

The round one gets the green (Same as the 50 amp)
The flat blad opposite may be marked "W" or may be silverish in color .. The white wires

The black wire goes to both sides.
 
lesd said:
I am interested in wiring up a short adapter cord to allow me to run minimal systems on regular
home power. Is there a guide for how this should be wired up? The plug side of the HM cable has poles, one of which is round.
Does the 115V 15 amp side get wired to both phases of the MH side ?
Click to expand...

lesd:
See: https://www.youtube.com/watch?v=i69Jc_c_NHI
 
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