Safe to charge via dryer outlet?

[ElectricEddy]

Yes, that's why I suggested an either/or switch.

30 Amp manual xfer switch (generator panel) feeding 2 permanent 30A outlets 14-30R & 6-30R, but money would be better spent on a chunk of 8/3 loomex or teck cable c/w 40A breaker for the EVSE. The breaker will run cooler and from what I've seen in the field most L2 EVSE's manufacturer specs require this. Canadian electric code would would require 2 dedicated circuits. I can't see it any different in the States.

[QueenBee]

Leave both the dryer and the EVSE plugged in all the time, but NEVER use the dryer when the EV is charging.

That is neither code, nor safe.

You are literally betting a possible fire that the circuit breaker will save the day.

Same could be said about having multiple receptacles on a 120 volt circuit. Circuit breakers save the day thousands and thousands of times a day.

NEC allows multiple 240 volt receptacles on one circuit so I'm wondering what would preclude someone from doing this (besides the obvious thing that it is a bit silly and not nearly as safe as a dedicated circuit.)

[Stanton]

Besides literally "playing with fire", I don't understand why someone would risk a $30k+ automobile on poor/risky EVSE implementations. For the record, I have used an EVSEUpgrade unit on a dedicated dryer socket in my garage since I bought my Leaf with no issues (I rarely plug/un-plug the unit).

[Nubo]

Same could be said about having multiple receptacles on a 120 volt circuit. Circuit breakers save the day thousands and thousands of times a day.

Two heavy-draw devices on a 240V circuit is essentially a planned, deliberate and extreme overload at high power levels. Breakers save the day, yes that's their job. But still, don't take foolish chances. Breakers can and do fail. 240V devices by their nature are both high-voltage and high-amperage. While overloads of any type are to be avoided, they're generally more severe in the case of 240V circuits. And there's a difference between an incidental overload, and designing an overload.

[QueenBee]

Same could be said about having multiple receptacles on a 120 volt circuit. Circuit breakers save the day thousands and thousands of times a day.

Two heavy-draw devices on a 240V circuit is essentially a planned, deliberate and extreme overload at high power levels. Breakers save the day, yes that's their job. But still, don't take foolish chances. Breakers can and do fail. 240V devices by their nature are both high-voltage and high-amperage. While overloads of any type are to be avoided, they're generally more severe in the case of 240V circuits. And there's a difference between an incidental overload, and designing an overload.

Anyway my point was just regardless of your opinion the NEC does allow multiple receptacles on a 240 volt circuit.

There are lots of situations were 240 volt with high amperage is designed that you aren't going to turn everything on at once and if you do that a circuit breaker/fuse is going to protect the wires. For example maxing out every circuit in your house will overload your service. If you and your neighbors all use too much power you'll overload the likely 25kva transformers that are often shared among many homes.

But like I said it's a bit silly and not nearly as safe as a dedicated circuit.

[garygid]

Technically, the 3-prong dryer socket is ungrounded, wired as 2 hot lines and the Neutral, right?

Then, the dryer is allowed to use the 10-30 Neutral slightly incorrectly as the chassis Ground, right?

[QueenBee]

Technically, the 3-prong dryer socket is ungrounded, wired as 2 hot lines and the Neutral, right?

Then, the dryer is allowed to use the 10-30 Neutral slightly incorrectly as the chassis Ground, right?

I guess that would be sora true since you'd connect this to the nuetral bus bar if they were seperated in the panel but I guess you could also say that it's technically the EGC and nuetral wire.

[CGKyle]

I've found this thread incredibly helpful. In my case I plan to extend my existing #10 wire another 10 feet from my dryer circuit through the wall into the garage. I'm having an electrician buddy do the work but I've already purchased an industrial grade 30 amp double pole double pole switch as suggested in this thread. It looks like a standard switch so the spouse can use it without intimidation. Heavier wire though would require a larger type of switch. Hopefully, like me, others can use this to kickstart their electrician into keeping to code, and keeping the install bills at a minimum. Then with my EVSE Upgrade I have the easiest possible plan for level 2 charging.

[QueenBee]

Heavier wire though would require a larger type of switch.

If the switch is not rated to accept a larger gauge wire one thing electricians will do is add a pig tail with the the largest gauge it does accept and then use the proper size wire nut.

[Rauv]

You are not allowed to use the dryer outlet for an EVSE. This is new to the 2014 NEC. See Art 210.17:

"An outlet(s) installed for the purpose of charging electric vehicles shall be supplied by a separate branch circuit. This circuit shall have no other outlets."

Check to see what Code cycle your town uses.