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mailman-ret's avatar
mailman-ret
Explorer
Jun 24, 2017

Converting 30 Amp Ext. Cord To Hook To 50 Amp TT

Several years ago, I replaced the female end of a 30 amp extension cord to one that hooked to a 30 amp outside screw on hook-up. We have visited CGs where passers by have gotten attached to other campers power cords. With a hidden extra cable I felt certain I could sleep with A/C with my health problems.

We just purchased a 2017 TT with a 50 amp hookup, so I will replace the old add-on with a 50 amp add-on connection so I can still sleep in the cool.

The DENALI has one 15,000 BTU A/C and front vent hole is wired for a second. With the all weather thermal package that it has, we will not add the second A/C.

Currently, I am hooked to a 30 amp box, using an adapter to hook to my 50 amp system. Once I get my conversion parts here, I will get out the ohms meter and starting at the 30 amp male plug, I will check to see what leads correspond to the terminals on the plug-in terminals, then hook the wires where indicated. I can't forsee any use for that additional wire. Could I be looking at that wrong?

24 Replies

  • ok.. i am NOT clearly understanding your intention

    you can NOT tun a 30 amp cord into a 50 amp cord
    a 50 amp cord has 4 wires that are a larger gauge wire
    and the 30 amp only has 3 wires, all your doing is creating a long 30amp dogbone adapter

    if you need a longer 50 amp extension you will have too buy one

    if you want to use the 30amp ext to plug the 50amp rv into a 30 amp socket
    just use the 30 male to 50 female dogbone
    and put it between the 30amp cord and the new 50 amp RV cord
    like you are now

    the 30 amp dog bone takes (1) hot leg and connects it to the (2) in your 50 amp cord

    but you Can NOT take (2) 50amp legs and connect them to (1) 30 amp rated wire in your 30amp cord with a 50amp male on the end of a (3) wire 30amp cord

    if your not lucky, you could end up with a 100 amp dead short when you tried to plug that in
    its against code and extremely dangerous
  • Yes... connect ground to ground, neutral to neutral, 30 amp hot to both 50 amp hots.
    Standard adapter does the same. Cord is just a long dog-bone adapter.
  • That additional wire powers half of your RV. So if you connect L1 and L2 together your plan should work.

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