Forum Discussion

holstein13's avatar
holstein13
Explorer
Aug 17, 2016

Has anyone ever used a 45 AMP adapter?

I usually require a 50 amp outlet to power my coach but sometimes, all I can get is 30 amps.

A year ago I saw this nifty 50 amp adapter that had two ends, a 30 amp male plus a 15 amp mail leading to a 50 amp female. The problem is, it doesn't work.

Every time I plug it in, it trips the 15 amp breaker on the pole. If I only plug in the 30 amp, I get an "Open Leg" fault" on my display. I've tried it at 3 different places always with the same result. Do these things even work? How can I test it with my voltmeter?

And I'm sure that someone will mention that 50 amp power is actually 100 amps total. I realize this so there is no need to mention it. But I'm sure it will get mentioned anyway. Few people read to the end of these posts.

ON EDIT: I should have mentioned that I have two adapters, this 45 amp and a 30 to 50 amp adapter. I use the regular adapter every time I have 30 amp available but not 50 amp. I was just hoping to use the 45 amp adapter occasionally.

EDIT #2:Thanks to the very informative tips, comments and suggestions on this post, I have decided to ditch my 45 AMP adapter and I switched to a 60 amp adapter (two 30 amps for a total of 60 amps). I am writing this comment from the glorious comfort of my coach cooled by two air conditioners. It's not as good as 100 amps, but it's better than 30.

Thank you all for your input. This is why I love this forum so much.

18 Replies

  • I would suggest throwing the "45A" adapter in the trash. IMHO those things are dangerous, or potentially dangerous, especially if there is a fault in the pedestal wiring.

    Basically, it connects one leg of the 50A to the 30A plug and the other to the 15A plug. The neutral (and ground) are connected to both. There are several problems or potential problems with this arrangement:

    1. As you've found out, it creates (what looks like) a ground fault that will trip a GFCI every time. Since the NEC requires that all 15A or 20A outlets that are outdoors be GFCI protected, the chance of this not happening is quite slim.

    2. If there are any 240V devices in your RV (which is not the usual case), you can readily have a live exposed male plug.

    3. If there is an outlet with reversed polarity, connecting the adapter creates a short circuit and leaving one end unconnected creates a live male plug.

    4. If there is an open or poor neutral connection on one of the outlets, the other neutral may well be overloaded. If the two outlets are on the same phase, it almost certainly will be; and if it's the 30A neutral that's open, the 15A one will carry up to 45A--a quite significant overload, and enough to be more than a theoretical fire hazard.
  • Maybe something else is on. Microwave and one air should operate on 30 amps. Mine does.
    I put my water and fridge to propane only when running the air.

    Could get an adaptive inverter that combines power with the 30 amps to temporarily cover additional loads.
  • ChooChooMan74 wrote:
    Those adapters work only in certain instances. For one, the pedestal 15/20 amp can not be a GFI. 2nd, This will only give you about 5400 watts of power instead of the 12000 watts of power that a 50 amp 120/240 connection will give you. So, you are still very limited to what you can use.
    Thanks, that is probably the answer. I never checked to see if it's a GFCI circuit but that would make sense.
  • smkettner wrote:
    Will not work in a GFCI outlet. Will trip every time as designed.

    Open leg is because one side is not connected. A regular 30-50 adapter will connect the 30 amps to both your main breakers.

    If you can find two outlets without GFCI then it will work. No need to test with a voltmeter. I still do not recommend it. Too much hassle. Your EMS should be able to manage power on 30 amps.... or rather what issue are you trying to resolve?
    Yes, of course. That's exactly what I do every time the 45 amp adapter doesn't work. I just use the regular 30 amp to 50 amp adapter. I was hoping to get 15 more amps so I could use the microwave at the same time as one air conditioner.
  • Will not work in a GFCI outlet. Will trip every time as designed.

    Open leg is because one side is not connected. A regular 30-50 adapter will connect the 30 amps to both your main breakers.

    If you can find two outlets without GFCI then it will work. No need to test with a voltmeter. I still do not recommend it. Too much hassle. Your EMS should be able to manage power on 30 amps.... or rather what issue are you trying to resolve?
  • What display?

    I'm not sure at this point what is wrong, but you need to understand that your 50A plug is actually 2 x 50A for a total of 100A available to the coach. So your adapter is giving you 30A available on one leg that is designed for 50A, and 15A on the other leg that is designed for 50A. So while a 45A adapter sounds like it is almost as good as the 50A, it actually is far less.

    I think you would be better off with a straight 30A male to 50A female adapter. Your second A/C might not work. Or your W/D, if you have them, might not work. All depends on how your coach is wired.
  • Yes I use the splitter. I have plugged into 2 30 amp receptacles using a 15 to 30 adapter on the 15 amp leg.

    I have plugged into a 30 amp and a 15 amp leg using a non GFI receptacle. It will not work with a GFI receptacle.
  • Those adapters work only in certain instances. For one, the pedestal 15/20 amp can not be a GFI. 2nd, This will only give you about 5400 watts of power instead of the 12000 watts of power that a 50 amp 120/240 connection will give you. So, you are still very limited to what you can use.