240 volts directly from wall outlet to MME built in charger

[Mrn]

This is just a thought experiment to understand wall 'chargers' better. Why do we need an intermediary wall device aka 'charger' between the generic 4 slot 240 volt wall outlet and the MME built in actual charger?

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[Jerrytball]

This is just a thought experiment to understand wall 'chargers' better. Why do we need an intermediary wall device aka 'charger' between the generic 4 slot 240 volt wall outlet and the MME built in actual charger?

Are you talking about like a regular dryer outlet and you plug in the charging cord that comes with the car? If that’s what you’re talking about I understand that doesn’t hold up too well that’s why you buy the permanently mounted. Now, if I could redo mine, I think I would’ve had them somehow mount the 240 plug on the wall mount the permanent charger next to it and they have a plug from the charger so I could plug it into that Wiring it straight to the power panel on the side of the house that way if I wanted to move, I could just unplug the charger and take it instead of having to have somebody come out there and hide all the wires or whatever.

 

[phidauex]

The wall device, the "EVSE" Electric Vehicle Supply Equipment, is there to make it safe to have what would ordinarily be extremely dangerous - a big floppy 240V extension cord that you accidentally drive over and drop into puddles.

If it were just an extension cord, then they would regularly catch on fire and electrocute people. Even when working correctly they would pop and arc when pulling them out of the car, which would rapidly damage the contacts on both sides. So it would "work", but would be a bad idea.

The EVSE does two important things - it communicates charge readiness with the car, and doesn't close the contactor until the car confirms connection (by a 12V pilot signal on one of the J1772 pins). The same system shuts off power when you push the button on the charge handle to release it. That way the pins are never "live" when disconnected from the car.

The other is to put a GFCI in the EVSE which shuts off in the event of a ground fault so someone walking into the garage doesn't get electrocuted.

I like Grizzl-E chargers for this reason - they keep this process as simple as possible. Anything else the charger is doing, like smart features, scheduling, apps, etc., are all just nice-to-haves, but not related to the core task of supplying safe AC current to the car.

 

[Mach-Lee]

You would not want to plug in a live 240V extension cord in the rain. Too high of an electrocution risk. The EVSE switches on and off power, and monitors for faults. If your are being electrocuted, it will switch off the power and save your life (this was part of the EV charging standard long before 240V GFCI breakers were put in code).

 

[Peugfan]

“Darwin Award”

 

[Maquis]

Please read the Wikipedia article on “J1772.”

 

[JDP That's Me in My MachE]

This is just a thought experiment to understand wall 'chargers' better. Why do we need an intermediary wall device aka 'charger' between the generic 4 slot 240 volt wall outlet and the MME built in actual charger?

I have been plugging into a 30amp 240volt outlet with the Ford cable for 2 years and 3 months and 35,000 miles with no problems. The outlet is wired direct to the whole house box by an electrician. No EVSE, no third party charger, no problems.

 

[BMT1071]

I have been plugging into a 30amp 240volt outlet with the Ford cable for 2 years and 3 months and 35,000 miles with no problems. The outlet is wired direct to the whole house box by an electrician. No EVSE, no third party charger, no problems.

The "Ford cable" is the EVSE.

 

[Aubury]

Another thing that people haven't covered is the EVSE tells the EV how much current it can provide. Makes it so you can just plug the EV into any EVSE, without having to adjust the current the vehicle will try and pull manually (Ford doesn't allow us to set how much power you can pull from an EVSE, most other EVs do allow you to make the charger draw less than the maximum of the EVSE), and not have to worry about potentially tripping a breaker.

 

[Rj786]

can someone comment on the post by JDP that he is safely using a 30amp 240v circuit with the Ford supplied charger that came with the car. My understanding is that the Ford supplied EVSE draws 40amp and not safe to use on a 30amp circuit.

 

[zvez]

can someone comment on the post by JDP that he is safely using a 30amp 240v circuit with the Ford supplied charger that came with the car. My understanding is that the Ford supplied EVSE draws 40amp and not safe to use on a 30amp circuit.

the ford portable evse draws 29-32 amps.

 

[Mach-Lee]

I have been plugging into a 30amp 240volt outlet with the Ford cable for 2 years and 3 months and 35,000 miles with no problems. The outlet is wired direct to the whole house box by an electrician. No EVSE, no third party charger, no problems.

can someone comment on the post by JDP that he is safely using a 30amp 240v circuit with the Ford supplied charger that came with the car. My understanding is that the Ford supplied EVSE draws 40amp and not safe to use on a 30amp circuit.

JDP, you are overloading your 30A circuit because the Ford Mobile Charger that comes with the Mach-E is set to draw 32A (and you're using it on a 30A breaker). It must be used with a 14-50 outlet on a 40A or 50A circuit breaker only. Using an adapter to convert a 30A outlet into a 50A outlet is not safe.

You are only allowed to charge at 80% of the circuit breaker's rating, so for a 30A circuit you can only charge at 24 amps. Since neither the Mach-E nor the Ford Mobile Charger can be set to 24 amps, you need to use a different EVSE designed for 30A circuits such as this.

And just because you've been doing it that way for two years doesn't mean it's right or safe. Problems can easily develop over time from chronic circuit overloading that can cause a fire down the road. If you have a fire and your house burns down, your insurance company may not cover the damages since you are doing something illegal.

 

[Maquis]

can someone comment on the post by JDP that he is safely using a 30amp 240v circuit with the Ford supplied charger that came with the car. My understanding is that the Ford supplied EVSE draws 40amp and not safe to use on a 30amp circuit.

I figured it was either a typo, or he doesn’t realize what breaker size he actually has.

 

[Aubury]

JDP, you are overloading your 30A circuit because the Ford Mobile Charger that comes with the Mach-E is set to draw 32A (and you're using it on a 30A breaker). It must be used with a 14-50 outlet on a 40A or 50A circuit breaker only. Using an adapter to convert a 30A outlet into a 50A outlet is not safe.

You are only allowed to charge at 80% of the circuit breaker's rating, so for a 30A circuit you can only charge at 24 amps. Since neither the Mach-E nor the Ford Mobile Charger can be set to 24 amps, you need to use a different EVSE designed for 30A circuits such as this.

And just because you've been doing it that way for two years doesn't mean it's right or safe. Problems can easily develop over time from chronic circuit overloading that can cause a fire down the road. If you have a fire and your house burns down, your insurance company may not cover the damages since you are doing something illegal.

It has to be a typo or, an improperly sized breaker for the circuit (though that wouldn't make sense if they're calling it a 30A circuit) or a broken breaker. Surely the mobile charger would trip the breaker since it's drawing 32A.

 

[jeffMachE]

The mobile Ford charger (sorry, EVSE) comes with a 120 v plug (5-15P) and a 240 v plug (14-50P). I don't believe you can plug into a "30 amp 240v" circuit (which implies a 14-30P) without an adapter. So OP is either is using an adapter or has his local wiring incorrect (against code to put a 14-50R on a 30 amp circuit).

In any case, the bigger issue to me is that 14-50R receptacles aren't really designed for daily plugging/unplugging. The weight of the plugs/cords will eventually cause the springs in the outlet to loosen up resulting in loose connections and increasing the chance of resistive heating leading to fire. Personally, I wouldn't be concerned about using the Ford mobile charger daily on a 240V circuit, but only if I was leaving it plugged in. Yes, it might fail sooner than a more ruggedized EVSE, but I consider that to be small issue.

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