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Need help with charging adapter

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Hello,

I just picked up my Tesla Model S last night and do not have a plug installed in my garage yet (that's next week). I thought I could make an adapter to use so that I could plug into my dryer outlet. It is an older 3 prong 30 amp plug. The adapter I made is not working. I get a red light when I plug it in. I'll attempt to attach pictures to this thread. Any help is much appreciated.

John
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The Tesla UMC requires a ground. You have nothing connected to the ground pin of the 14-50R. The 10-30P does not have a ground pin, only a neutral that you connected correctly. If you connect the neutral to ground inside the 14-50R, it should work.

Be very careful! Connecting neutral to ground violates many modern wiring standards!!! On the other hand, doing that inside the inside the 14-50R does not make a neutral to ground connection in your house. Be sure to label the cable for EV charging only, and do not use it for an RV.

Be sure to dial the Tesla charging current back to 24 Amps to avoid popping a breaker or overheating any wires.


If you want to buy an adapter, here is a link: NEMA 14-50R to 10-30P Adapter Also, Tesla used to make a 10-30 adapter for the UMC. If you look around, you might be able to find one to buy.
 
Ok, I fixed the ground and it is now working. I read somewhere on the forums that if you have a Federal Pacific Panel box that you should NOT do what I am trying to do.......and of course this house has a Federal Pacific Panel. Grrrrrr. Ok, so I turned the amp down to 20 amps and will keep an eye on it. I won't leave it on overnight. Just need to get me through the weekend and back to my other house on Monday (where I will have a Tesla wall unit installed on Monday).

- - - Updated - - -

The warning against using this with a Federal Pacific Panel box has me a little nervous. I turned the charging amps down to 20 amps. I've checked the cable running from the dryer plug to the garage and it is not warm at all. If the cord does not get hot, then should it be ok for this weekend?
 
The warning against using this with a Federal Pacific Panel box has me a little nervous. I turned the charging amps down to 20 amps. I've checked the cable running from the dryer plug to the garage and it is not warm at all. If the cord does not get hot, then should it be ok for this weekend?

Generally, if nothing is getting hot, you are OK. The problems come from spots that you don't check that do get hot. If you are concerned about the Panel, definitely feel for hot spots there. Of course, make sure that you don't touch any high Voltages.

A good, way to be extra careful, is to wear insulated shoes and stand on an insulated mat, then put one hand in your pocket, and do your feeling around with the other hand. It is electrical current through the heart that kills people, the method I described makes sure that any currents through your body caused by touching the wrong spot only go through the probing hand. If you make a mistake, it will give your hand a jolt, but probably nothing worse than that. Be careful!

Interesting factoid: The power frequencies that we use were chosen for convenient design of motors and generators. An unfortunate coincidence is that 50 and 60 Hz are pretty close to the optimum frequencies for killing people. Electric shock - Wikipedia
 
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