Safe to charge via dryer outlet?

[desiv]

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."

Although that isn't saying you can't use a dryer outlet, just that you can't use it if a Dryer is also wired up to it at the same time.
That probably is saying the "switch" isn't an option, code-wise...
(which doesn't surprise me..)

desiv

[Phatcat73]

I had a conversation with EVSE upgrade regarding wiring my Bosch unit to a 3 wire dryer outlet. Keep in mind they sell an adapter for both old and new dryer outlets. Tesla offers similar adapters. Bottom line it's not an issue, the ground and neutral return to the same source essentially.

I found that if you speak to an electrician he'll tell you that you can't do it as it violates code. However speak to an EE and he'll tell you it's technically safe and acceptable.

There's isn't the magic ability for an EVSE to differentiate GND from Neutral.

My Bosch unit works fine with the $10 dryer cord.

[smkettner]

Is a switch not permitted either?
Once switched there is only one outlet available on the branch circuit.

[XeonPony]

Seems there is great confusion on ground Vs Neutral.

They are NOT the same thing!

Neutral returns to the pole, phase to phase is 240-220V and phase to Neutral will be 120-110V

Ground is a fail safe, the transformer on the poles will have an earth ground.

Your panel will have a hard wired earth ground as well, and at only one point will the two be bonded Neutral and ground in the panel.

The grounding conductor will on average be a SMALLER conductor then the current carrying conductor (This being the neutral)

Under no circumstance should you ever use the earth ground as a neutral as it was never meant to carry a continuous load, it will all so have the potential to energize all the body casings of appliances above earth levels if you have a faulty grounding electrode!

Using the grounding system offers you electrocution risk, fire risk, blown electronics risk, large voltage drops, either all at once or in various combinations.

In a 240 device unless required the neutral wire can simply be cut, capped, and taped and ignored from then on. Only your two hot phases and ground need be hooked up

All so it is best to use a GFCI Breaker for additional protection (Check to ensure compatibility with the evse to avoid nuisance tripping)

Best choice for external routing is TEC90 Cable it looks good and is incredibly sturdy armoured cable, but will be pricey, but for a triple insulated armoured cable it is best of the best!

Using a proper power transfer switch will be safe, how it relates to code I do not know.

[Phatcat73]

Makes you wonder how evse upgrade and Teslas range of adapters compensate between an neutral or ground based adapter.

I suspect they don't.

[JeremyW]

Under no circumstance should you ever use the earth ground as a neutral as it was never meant to carry a continuous load, it will all so have the potential to energize all the body casings of appliances above earth levels if you have a faulty grounding electrode!.

A "old style" dryer outlet (NEMA 10-30) has two hots and a neutral, no ground. So in the EV application you're using a neutral conductor as a ground, not the other way around.

[desiv]

Under no circumstance should you ever use the earth ground as a neutral as it was never meant to carry a continuous load, it will all so have the potential to energize all the body casings of appliances above earth levels if you have a faulty grounding electrode!.

A "old style" dryer outlet (NEMA 10-30) has two hots and a neutral, no ground. So in the EV application you're using a neutral conductor as a ground, not the other way around.

So you can't use "the earth ground as a neutral," but you can use a neutral as a ground apparently?
(Not a big deal, just confusing. But I probably would never actually understand it anyway... )
I don't think Wikipedia is a font of verifiable data, but here's what it says:

NEMA 10 devices are a curious throwback to an earlier time. They are classified as 125/250 V non-grounding (hot-hot-neutral), yet they are usually used in a manner that effectively grounds the appliance, though not in a manner consistent with most modern practice.

As commonly used, 10–30 and 10–50 plugs have the frame of the appliance grounded through the neutral blade. This was a legal grounding method under the National Electrical Code for electric ranges and electric clothes dryers from the 1947 to the 1996 edition. Since North American dryers and ranges have certain parts (timers, lights, fans, etc.) that run on 120 V, this means that the wire used for grounding is also carrying current. Although this is contrary to modern grounding practice, such installations remain common in the United States and are relatively safe, because the larger conductors used are less likely to be broken than the smaller conductors used in ordinary appliance cords, and the current carried on the neutral conductor is small.

That being said, I wonder how they wired my plug.
On the "order," it said to add a dryer plug for an Electric Vehicle.
But when the electricians showed up, they DID ask to see the install manual (which I had ready for them to see), that specifically says GROUND and their reciept also said for an EV.
I didn't check to see if they ran it to ground or neutral tho...

Hmmm... Maybe I'll open that panel one of these days and check..

desiv

[smkettner]

That being said, I wonder how they wired my plug.
On the "order," it said to add a dryer plug for an Electric Vehicle.
But when the electricians showed up, they DID ask to see the install manual (which I had ready for them to see), that specifically says GROUND and their reciept also said for an EV.
I didn't check to see if they ran it to ground or neutral tho...

Hmmm... Maybe I'll open that panel one of these days and check..

desiv

Either way the wire is connected the same in the main panel where Neutral and Ground are bonded.
As a ground they may have dropped a size to #12 but I think it would be proper to be #10 same as L1/L2.

[desiv]

Dryer and the EVSE connected to the same circuit can be done??
https://www.youtube.com/watch?v=uzdMqti6qGA" onclick="window.open(this.href);return false;

Somewhere in that video they mention a company that had a product to do that..

I remembered this thread (and I think I've seen it mentioned elsewhere) so thought I'd post.
That said, I'd guess it's pretty expensive.
The only situation it might be realistic would be if you couldn't afford to add an upgraded circuit to the house, or maybe a landlord that will let you add this, but not a new circuit (although I don't see that last one..).

Either way, interesting tech.

desiv

[Deleonac]

I have a Blink HQ EVSE, 30 AMP, 240 Volt. Calls for hard wire on a 40 amp circuit. My old dryer plug has a 30 amp circuit breaker on it. Is this why i keep getting a red fault code? I've connected L1, L2, and Ground wires only.