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A 10-30 has a connection to ground through the neutral. Since an EVSE does not use neutral it is perfectly acceptable for it to use the neutral wire as a safety ground.
I believe sub-panels are separated, so not knowing if the branch runs off the main vs sub-panel may contribute to the cautious approach.
 

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Discussion Starter #22
I too have been considering getting an EVSE to plug in to my 10-30 dryer outlet, but also have concerns about the ground. I‘m definitely going to have an electrician look at the situation before I proceed, but that’s just me!
Just to be on the safe side I called the electrician that put the plug in to get clarification as well. But it does appear everything is fine. There are a lot of folks out there using Nema 10-30 for their EV Charging and have not seen one post identifying it as a problem.
 

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A 10-30 has a connection to ground through the neutral. Since an EVSE does not use neutral it is perfectly acceptable for it to use the neutral wire as a safety ground.
Thanks and no offense, but I would prefer to trust the judgement of an electrician who has looked at my wiring. It is my understanding that it hasn‘t been “Code” to wire these outlets with the neutral connected to the ground for about 25 years. Surely there are good reasons for this.

Yes, “old work” is still allowed to retain this setup, but only for ”listed” appliances. Maybe EVSEs have been added to the list?
 

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Discussion Starter #24
Well, just to continue to muddy the water. I called Chevrolet and they gave me a number to their Chevy Bolt Specialists (833) 382-4389. Of course they were closed (8am-7pmET). So will call on Wednesday and see what they have to say. Also, when I went through Qmeric or Qmerit their Electrical Contractor called me and said I had all I needed to put in a charger and their was no reason for him to come out. Just find a charger I wanted that matched the plug I had, plug it in and go. One caution, don't exceed the circuit breaker amps (i.e. the 80%). How can something so simple get so complicated? Oh well, to dark to golf, might as well stay busy.
 

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Discussion Starter #25
Just to be on the safe side I called the electrician that put the plug in to get clarification as well. But it does appear everything is fine. There are a lot of folks out there using Nema 10-30 for their EV Charging and have not seen one post identifying it as a problem.
Oops, I'll take that back. A com[any called Cripple Creek has posted negative (i.e don't use Nema 10-30 for their EV Chargers because of the ground). Point, "their EV Chargers". So what about the rest. Water continues to get muddier.
 

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Oops, I'll take that back. A com[any called Cripple Creek has posted negative (i.e don't use Nema 10-30 for their EV Chargers because of the ground). Point, "their EV Chargers". So what about the rest. Water continues to get muddier.
Pretty sure that 's "Clipper Creek", the same folks you chatted with per post #14.
 

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Discussion Starter #27
Thanks, You are right, Clipper Creek. This whole EV Charger thing is becoming more of a pain then it should be.
 

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Oops, I'll take that back. A com[any called Cripple Creek has posted negative (i.e don't use Nema 10-30 for their EV Chargers because of the ground). Point, "their EV Chargers". So what about the rest. Water continues to get muddier.
Let me see if I can clear up some of the confusion. There are two separate lines: safety ground (which is green or bare wire), and neutral (which is generally white). Both are at the same potential (0V) and are connected together at a single point in the house electrical system in the main electric box. The key to understanding the difference is that the safety ground is not supposed to carry any current except in fault conditions, while neutral is designed to carry current from hot lines.

The 10-30 is weird because it only has a neutral line and no safety ground. But as previously stated all neutrals in the house are supposed to be connected to ground in the main electrical box. Here's where it gets complicated. In a fault situation that neutral in the 10-30 will function as a safety ground as long as it is actually connected to ground in the main electrical box. If it's disconnected anywhere along the way, then the circuit is floating and the current has nowhere to go. That's when the trouble starts.

So, the complication is risk management. If you are not pulling 120V on the circuit, which EVSEs do not, then there is no current on the neutral of a 10-30. Since that neutral is wired to ground in the main electrical box, and that it is not carrying current, it is functionally equivalent to a safety ground as long as it's properly connected.

Hence that's why the electrical contractor stated that there was nothing to do.

Let me add one additional safety factor here. Every EVSE does a ground check during its power up sequence. If it detects no ground, it throws a fault and will not operate. So even in the rare case that the 10-30 neutral were somehow disconnected from the ground in the main electrical box, the EVSE would not work.

Now you certainly are welcome to call out another contractor and have them tell you the same thing. Clipper Creek is likely listening to their lawyers who are telling the staff "Tell the customer no. If something happens, then it isn't our fault."

At this point it's all about your risk tolerance. Personally, I've had a dryer plugged into a 10-30 for the 25+ years I've been in my house, So, I had no problem using that 10-30 for the EVSE that I eventually bought, which came with a 10-30 plug. It boots fine and operates fine.

If that level of risk is too much for you, then have the electrical contractor come out and have them rewire the 10-30 to either a 14-30 or a 6-30, each of which has an electrical safety ground. The 14-30 also has a neutral, the 6-30 does not.

I hope that this information that explains how everything works will help you to make a final decision.

ga2500ev
 

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Clipper Creek is likely listening to their lawyers who are telling the staff "Tell the customer no. If something happens, then it isn't our fault."
As you noted, it is possible the neutral line is not grounded. My understanding is, if the circuit is connected to a sub-panel, this is a possibility. Sub-panels are 4 wire connected to the main panel, neutral and ground are separate. So, CC may be airing on the side of caution and simply leaving nothing to doubt.
 

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As you noted, it is possible the neutral line is not grounded.
It would not be connected to the ground at the sub-panel, but neutral is still bonded to ground at the main panel.

This is all much ado about nothing. Plug an EVSE in and it will tell you whether it has a proper ground or not.
 

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Discussion Starter #33
Thanks for your inputs. I have talked to the electrician that put in the 220v/30amp circuit in a few years ago and discussed the Nema 10-30 plug along with the issue of it neutral or ground. Bottom line, it's grounded and meets code. I did talk to the Chevy Bolt Specialists at Chevy and they referred me to Qmeric who is who they referred folks to wanting a charging system installed. I have talked to Qmeric and waiting for a return call from their electrician, whom I did talked last Saturday and at that time he said I had everything I needed, just get a charger that has a plug that matches mine and make sure not to exceed the amps on the circuit (i.e. 24 amps on a 30 amp circuit). Where all this started is when some folks started raising the issue about ground and neutral. I don't fully understand it all, but I have used the plug for years to run a 220 volt table saw without issue and based on conversations with my electrician and the fact that there are numerous companies out there selling chargers with the Nema 10-30 plug I don't see where the problem will be. So, consider the issue resolved. Now I just have to determine how much I want to spend on a charger. Really leaning toward the adjustable 32amp charger from PRIMECOM. THANKS AGAIN TO ALL OF YOU WHO WEIGHED IN ON THIS AND TOLERATED AN OLD MAN'S ANXIOUSNESS TO DO THE RIGHT THING.
 

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Thanks and no offense, but I would prefer to trust the judgement of an electrician who has looked at my wiring. It is my understanding that it hasn‘t been “Code” to wire these outlets with the neutral connected to the ground for about 25 years. Surely there are good reasons for this.

Yes, “old work” is still allowed to retain this setup, but only for ”listed” appliances. Maybe EVSEs have been added to the list?
The problem with the 10-30 is there is no dedicated ground on a 240/120V circuit. However, this becomes irrelevant when you are running a pure 240 device on it when you have a circuit directly wired to a main breaker box. The only case where you'd have a difference between a 6-30 (2 hots and a ground) and 10-30 receptical is coming off a sub panel. In this case, there may be a small difference (less than 5V) between the potential of the neutral line and ground. This can cause problem as the vehicle is grounded to the neutral voltage, but it's hard to see where practically this would be a problem.
 

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Discussion Starter #35
I believe sub-panels are separated, so not knowing if the branch runs off the main vs sub-panel may contribute to the cautious approach.
I'm glad you guys know what you are talking about. To be clear, the NEMA 10-30 220/30amp female plug in the garage is run straight to the panel in the basement and is on it's own 30 amp breaker (i.e. nothing else runs off that breaker).
 

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I'm glad you guys know what you are talking about. To be clear, the NEMA 10-30 220/30amp female plug in the garage is run straight to the panel in the basement and is on it's own 30 amp breaker (i.e. nothing else runs off that breaker).
So that means you are limited to a 24A EVSE.
 

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....Monte, you are good to go. Get your PrimeCom. [Set it to 24A] Plug it in. Enjoy your Bolt.
Sorry, I shouldn't jump in.
 

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ga2500ev said:
....Monte, you are good to go. Get your PrimeCom. [Set it to 24A] Plug it in. Enjoy your Bolt.
Sorry, I shouldn't jump in.
I have talked to Qmeric and waiting for a return call from their electrician, whom I did talked last Saturday and at that time he said I had everything I needed, just get a charger that has a plug that matches mine and make sure not to exceed the amps on the circuit (i.e. 24 amps on a 30 amp circuit).
No. Actually you shouldn't jump in. @Monte clearly understands what to do, as is indicated by multiple posts in this thread.

ga2500ev
 

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Discussion Starter #40
So that means you are limited to a 24A EVSE.
[/QUOTE Yep, but based on our driving habits, not even sure I need that much. Still trying to decide if I want to spend the money. So far the standard 110V charge is doing us fine. Time will tell.
 
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