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NanciL's avatar
NanciL
Explorer II
Nov 22, 2014

Electrical truck to trailer connection question

Can I use an extension cord to connect between my truck connector and my trailer cable connector ?
If yes do I have to worry about a voltage drop if the distance is too long.
I park my trailer in a trailer barn that I built several years ago, and this year I added next to it an attached truck port where I now park my truck.
Each time we want to work in the trailer or have heat/lights on in it, I have to back the truck out and back it up to the trailer to plug it in.
I am thinking that if I had an extension cord, I could leave the truck parked in the truck port and then just using it , plug into the trailers cord.
I have space to run under the side of the two buildings, but haven't measured the distance I would need for the extension.
If I can do this; what is the maximum length I can use for the extension cord, (naturally I will use the shortest that I can)

Jack L

22 Replies

  • RoyB's avatar
    RoyB
    Explorer II
    Your trailer 12VDC Parasitic Drains will run your truck start battery down just as easy as it will run down your trailer battery. Not a good idea to me.

    I would install 120VAC to your "trailer barn" and plug the trailer shore power cable into an installed RV 30AMP pedestal type receptacle or at least into the 120VAC Receptacle using a RV30A-15A long 'dogbone' type adapter (WALMART). This will run your trailer on-board converter/charger unit to keep your trailer batteries charged up.

    Rule number one in my book is never mess with the truck 12VDC start battery system as the truck is the only way you can get back home with...

    Roy Ken
  • Don't understand why you need to have your truck plugged into the trailer to have trailer lights or heat???

    Where's the trailers battery? Can't you just plug in the trialer to shore power?

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