Did I screw up horribly? - installed my own 240v outlet

So the questions are: What size wire are you using from the breaker box to the outlet? What size circuit breaker are you using? Is this is truly a dedicated 240v/ (30-40amp) circuit, then you can simply change the outlet. BUT!!!--- if this is not the case you need to rethink/redo. There are very specific SAFTEY reasons why the outlet shape/size is different between a 120volt and 240volt circuit. The way you have it now, someone could ignore your "240volt" marking and plug a regular device into the outlet. NOT a good idea! If you're not familiar with different breaker sizes, wire sizes, amps, volts, and line voltage drops, FIRST: Turn off the power to this outlet and do NOT use it! SECOND: Hire a certified electrician to install a new 240volt circuit and outlet, that is properly sized to the amperage you need.

 

YIKES!!!! Now I see why local governments require permits and inspections. If you really have 240V going to that outlet, you need to replace it with a 240V outlet before something gets destroyed or someone gets hurt or killed. That is a humongous code violation and really dangerous.

I'll reluctantly give this advice:
To use just two hots and a ground, install a NEMA 10-30R. Make sure the wires feeding it are at least #12 so they can handle as much current as the receptacle (30A). A 15A 2-pole breaker is sufficient for the car's charger, but you can go as high as a 30A breaker since it has a 30A outlet and wiring. Then you can make an adapter to connect the NEMA 5-15P on your EVSE cable to is. Then, keep the adapter connected to the cable so that it can't get left in the outlet.

The better advice, more strongly urged is:
Hire an electrician. Something tells me you don't know enough to make this a safe installation. There are lots of little details and can cause a fire or hurt someone if you do them wrong.

 

Connecting the second phase to the "neutral" terminal of the 15 amp 120 VAC receptacle will make the metal "frame" of the duplex receptacle and everything connected to it, including a metal box live. Touch the metal and having your feet grounded will likely kill you.

 

two things:

1) you need to install a proper 240v receptacle to code. including the correct wire size and circuit breaker.
2) you need to convert the prime evse to 240v, cost is around twenty dollars. see the appropriate thread here.

 

I am not an electrician nor do I claim to be very knowledgeable about electric work around the house. But even with my very little knowledge, I can see 240v feeding to the 120v outlet is a very dangerous potentially life-threatening, and most likely fire hazard code violation. Yeah, if I was you, I would shut off the breaker feeding that outlet immediately... and consult a certified electrician to get a proper installation of a 240v outlet.

 

Merely???? That's the whole point. Without the adapter, you have made a death trap.

Do you see what's in bold there?

Rob's adapter plugs into a 240V outlet. It's meant to be left attached to the EVSE cable, not the outlet so no one can accidentally plug in a 120V device. You have no adapter. Anybody can plug any old 120v tool or appliance into that outlet you have installed and blow it up or kill themself with the 120V that's likely to be present on any metal surface the item has. If you install a NEMA 10-30R they can only plug in stuff made to run on 240 volts -- or your adapter which should be connected to the charging cable.

If you didn't already know this stuff you're going to hurt someone and you really need to get someone in there who knows what they are doing. I'm not just guessing. I'm an electronics engineer and industrial electrician. I cannot warn you strongly enough of the danger your outlet poses. I don't think I've ever been more scared of something someone did with electricity. And that's saying a lot.

 

Beyond getting that outlet configured correctly, perhaps another question you should ask yourself is if you really need to charge the Prime at 240V. It takes roughly 5.5 hours at 12A @120V. If you use the lower current (8A @ 120V) it takes around 8 hours to charge a “fully” depleted battery. I’ve been happily charging in 8A mode for the past two months. Initially I had been thinking of installing a 240V outlet, but I’ve found it wouldn’t do me any good. The Prime charges while I sleep. Perhaps your situation is different than mine.

If you have a full EV vehicle I could understand the need for a 240V charging outlet.

 

The rationalization used by people who wire an outlet this way usually goes like this:

It's fundamentally the same as making an adapter cord.
It's clearly labeled as 240 VAT and Car charged so no one will misuse it.
I'll make sure everyone understands.
I'll undo it before I sell the house.
Code is just for professionals.

But what do you do when you electrocute yourself and someone comes along to unplug it? What happens when someone replaces that trim plate, removing your warning? What happens when your 10 year old plugs in a vacuum cleaner? What happens when the new home owner does not understand what 240 VAT means and plugs in the old aluminum bodied hand drill he inherited from his dad?

The proper way to do it is to install a 240 Volt receptacle and then swap out the ESVE cord's plug for a 240 volt compatible plug. Second best is an adapter that is glued or otherwise permanently connected to the plug of the ESVE cord.

 

With so much good advice being given, and which will apparently be completely ignored, my 30+ years of military and civilian electronics and electrical experience and maybe even just 'people experience' leads me to say......

Laaadieeeessss and Gentlemen......may I present to you the next contestant in this years gameshow "2021 Darwin Awards". Please place your over and under bets......

 

But this doesn't work with Toyota's EVSE cord, because there is a temperature sensor embedded in the plug. Cut off the original plug for replacement, and that sensor is gone. IIRC, that disables the system.

 

Maybe this is why Rob no longer visits here?

Rob's version can be used improperly, but at least it comes with warnings and can easily be made captive to the EVSE cord. But your version is not captive, and is much more accessible to other people ignorant to its intended use, so has a far higher likelihood of being used improperly and catastrophically.

There is a very important reason that you cannot buy a pre-made version this adapter from any regular retailer in the U.S., the legal liability is very high. If you really want a pre-made one, I wouldn't be surprised if you just might find it on Alibaba.com, but that isn't U.S.-based.

 

That's your best bet. A little advice. When you label it, the label should emphasize that it's a single purpose adapter. You will want to make sure it's readable and understandable.

 

Large sigh of relief here. It's very likely that you saved someone's life. Now, when you make that adapter, make sure it's secured to the cable and not left hanging from the dryer outlet when not in use.

By the way, when you wrap the wires onto the terminals on the plugs, do you know which way to wrap it? It makes a big difference.

 

Good catch, Fuzzy. I believe you're right; cutting off the plug and replacing it isn't an option.

 

Given what you have already done.......YOU should not pick any of them.
Seriously.

And the big question is: Did you plug your 120 V charger into that outlet ?
If so, did it smoke anything ??