Help Converting Gen Set Wiring

:8ball: :question: Hello I Have A Question, I Have Just Bought A Travel Trailer It Has A 110/120/30 Amp Power Cord I Have A Gen Set That I Want to Use As My Main Power Source "Where I Will Be Using The Trailer Has No Power Available At All " The Gen Set Has 2, 120/15 Amp Sockets And 2, 240/20 Amp Sockets With The Air Conditioning, Refrigerator, Lights, TV, And Misc Appliances Running I Will Exceed The 15 Amp Service From The Gen Set On A Single Line So What I Want To Do is Run Off Of My 220/20 Amp Service So I Went To The Hardware Store Bought
10 Gage 4 Conductor Wire
1,30 Amp Socket
1 Handy Box
1 Cover
2 240/20 Amp Plugs
So I Can Plug In "The Home Made Converter" Without Modifying The Gen Set Or The Cord Going To The Trailer Want To Leave My Options Open For The Future With The Trailer And The Gen Set
Thinking That This Is What I Will Need To Convert The 240/20 Amp Side Of The Gen Set Line To A Single 120/20 Amp Service To Power Up The Camper Without Stressing Out The Gen Set And Burning It Up Now How Do I Wire It So I Don't Make The 4th Of July In March And Will This Even Work Please Help Thanks So Much, Ron :blackeye:


Senior Member
Help Converting Gen Set Wiring

Keep in mind that 30 amps is the MAXIMUM the trailer can handle. Generally you will (or at least could be) be using less. I plug my 30 Amp trailer into a 15 amp socket all the time, and haven't had a problem yet. Obviously, you don't want to run the AC, the microwave and a vacuum cleaner at the same time...

Your first step should be to see what your generator can put out. Take the CONTINUOUS rating (not the maximum rating) and divide by 120 to get the continuous current. For instance, 3600 continuous watts = 30 amps, which is your trailer maximum, so anything over a 4000 watt (peak) generator is overkill. I run a 2800 watt generator, which is just barely enough after I installed an 'easy start' kit in the AC. It has a round, high current, 120 volt, locking socket on it, so I just wired the plug for that to a 30 amp RV socket and it works fine with a little care in power usage.

Let's remember what 240 volts is. It is 2 wires with 240 volts between them, and a neutral third wire in the middle. Therefore, from either power wire to the neutral is 120 volts, and you could wire this to a socket to get 20 amps. But 20 amps is the most you can get out of it, and any attempt to combine power from any of the other sockets will likely not work unless the generator is specially set up to allow that.


New Member
Help Converting Gen Set Wiring

YIKES ... I don't like the sound of this. :eek:

The 240 volt side of the generator is two 120 volt windings 180 degrees out of phase .... they cannot be combined into a 30amp RV plug!!!

:evil: Avoid the smoke ... just buy a pre wired 120v 15 amp to 120v 30 amp adapter from Wallyworld ;) and give it a try. I run a 50 amp Montana off the 20 just fine .. as long as you spread out the load. :laugh:

New Member
Help Converting Gen Set Wiring

The solution is simple not the best
First your gen set is 240V AC sinlgle phase @ 20 amp
240 x 20 = 4800 watts give or take a watt
240 through a step down transforem 2:1 = 120V
4800 x .707 / 120 = 28.25 amps

28.25 Amps @ 120 VAC should be a real world
yeild from your Gen. set.

BUT a 5 KW transform will not be cheap
and it is heavy .

Sell your generator and buy the correct one with a
noise dampening kit propane powered

Quiet clean and easy to use.