Nema 6-20P for EV Charging?

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Hi, currently at home we charge with level 1 through a regular wall outlet. I would like to improve the charging situation at home, now that I'm selling the Bolt and the Prologue will be my only vehicle. When I had the Bolt and Prologue I could charge one and drive the other LOL.

Our home is older and rented so I'm trying to keep the costs low on this, that's why I'm not going with a 14-50 outlet/circuit. If I wanted that the whole house would need to be upgraded or something.

My question is, if I have a professional electrician install a Nema 6-20P outlet in the garage (with landlords permission of course) do those suffer from the same problems as the "cheap" 14-50 outlets where they melt after a few months? I would be using a Schumacher SC1455 charger which can do 16A at 240V using this type of outlet.

The reason I am willing to spend a little bit of money on this is we pretty much are always charging 24/7 with the current setup. If I don't charge during peak times, well, I don't think the car would ever charge. With the L2 charging, even at 16A, we could change our PG&E rate plan to the EV one where night time is quite a bit cheaper and only charge at those times.
 
Is there a single outlet in your garage that's on its own breaker? My garage has a single nema 5-20 to its very own circuit with nothing else sharing it for some reason and it's really high up on a wall. Garage opener was installed in the middle and there's also an outlet on the ceiling for it.

If I ever did get an EV I would swap it out for a 6-20 and swap the breaker to a double pole and leave the wiring and use the neutral wire as a second hot wire and mark it red. can't be a neutral color like white or gray. If I really wanted more charging speed I'd fish wire with the old one and enlarge the outlet hole but I'd have to make sure I don't exceed the amperage limit for the breaker assuming everything can draw at peak and the wiring going to the house.

You can increase the voltage but can't increase the amperage. Is there any outlet like that in yours. You may be able to just swap the breaker and outlet yourself to something that isn't higher amperage and use the neutral as a second hot and marked as such and put it back together. Once you're out the house and the LL would be none the wiser. 240v with I believe is 80% of 20a would be 3,840w or so and I'd be ok with that.
 
6-20 should be fine. Those are single outlet receptacles, right? I don't think you're going to find anything in that which won't be industrial/commercial grade. And it only needs to be wired with 12 AWG Romex and a 20A breaker, which might already be there. If you really feel strongly about it, you can ask for Hubbell or Bryant. But I'd think even Leviton or Eaton with that kind of receptacle is going to be commercial grade, which are generally designed to be more durable over more insertion cycles. It may not make that much of a difference for a plug that doesn't move much.

My understanding is that the biggest fire risk is from a poor connection with a high current. A good connection will have pretty much zero resistance compared to the load. The biggest issue is when the connectors get worn, the contact is poor, and the resistance goes up. That will create heat locally. There are also issues when the wire connection to the receptable gets loose. That's why a lot of electricians don't recommend push-in backwiring, which isn't going to be in a 6-20R. It might also make sense to retighten the connections periodically.

Not sure how long these outlets last. If the receptacle is getting weak, it will be pretty obvious when a plug falls out much easier. I have found many commercial-grade receptacles don't necessarily require a whole lot of insertion force, but they're supposed to maintain better contact longer (and over more cycles).

And just a minor point, but P means plug and R means receptacle.
 
Ive seen ev rated receptacles at HD. I assume they’re designed for a longer duty cycle. Might want to look at that…
 
Ive seen ev rated receptacles at HD. I assume they’re designed for a longer duty cycle. Might want to look at that…

Not in a 6-20R though. I think it's just 14-50 with EV-specific versions, which can provide Level 2 charging - typically 32A at 240V.

I did find that there are some 6-20 duplex receptacles. Leviton has them in standard oval and Decora.

5822-W_610x_crop_center.png


But most are single: mostly round requiring a special plate.

5461-W
 
Not in a 6-20R though. I think it's just 14-50 with EV-specific versions, which can provide Level 2 charging - typically 32A at 240V.

And 6-20 is meant for 220-240V. I have taken out old two-prong receptacles that said they were rated for up to 250V, but I’m not sure who would have done that.
 
Use an L6-20 it has thicker pins and locks in place. They still fit is a single gang box. I think the construction is the same as an L6-30 (rated for 30 amps) just a different physical keying to prevent a 30 amp load from being plugged into a 20 amp circuit.
 
Hi, currently at home we charge with level 1 through a regular wall outlet. I would like to improve the charging situation at home, now that I'm selling the Bolt and the Prologue will be my only vehicle. When I had the Bolt and Prologue I could charge one and drive the other LOL.

Our home is older and rented so I'm trying to keep the costs low on this, that's why I'm not going with a 14-50 outlet/circuit. If I wanted that the whole house would need to be upgraded or something.

My question is, if I have a professional electrician install a Nema 6-20P outlet in the garage (with landlords permission of course) do those suffer from the same problems as the "cheap" 14-50 outlets where they melt after a few months? I would be using a Schumacher SC1455 charger which can do 16A at 240V using this type of outlet.

The reason I am willing to spend a little bit of money on this is we pretty much are always charging 24/7 with the current setup. If I don't charge during peak times, well, I don't think the car would ever charge. With the L2 charging, even at 16A, we could change our PG&E rate plan to the EV one where night time is quite a bit cheaper and only charge at those times.

Before you invest in this architecture make sure your ride can benefit from it.
I know the early teslas did not benefit from a 20A connector and had a software imposed 15 Amp limit at 120.
The next step up required 240V.
 
Before you invest in this architecture make sure your ride can benefit from it.
I know the early teslas did not benefit from a 20A connector and had a software imposed 15 Amp limit at 120.
The next step up required 240V.

The Prologue can do up to 12A at 120V, but the plug I'm looking to install would be 240V so this would be a non-issue. Thank you though!
 
Before you invest in this architecture make sure your ride can benefit from it.
I know the early teslas did not benefit from a 20A connector and had a software imposed 15 Amp limit at 120.
The next step up required 240V.

6-20 is meant for up to 20A at 240V. It's kind of oddball for specific 240V applications that are in between electric stoves/ranges/dryers and normal 15/20A at 120V. Maybe for small A/C units. But it would seem to bridge the difference between a Level 1 charger and a bigger Level 2 charger.
 
6-20 is meant for up to 20A at 240V. It's kind of oddball for specific 240V applications that are in between electric stoves/ranges/dryers and normal 15/20A at 120V. Maybe for small A/C units. But it would seem to bridge the difference between a Level 1 charger and a bigger Level 2 charger.

Oh yeah, I think 3.8kw would be SO much better than 0.96kw plus I think with charging losses (for example, on the Prologue there's always some sort of fan running when charging, even when it's cold outside), the efficiency of charging will be much better!
 
Oh yeah, I think 3.8kw would be SO much better than 0.96kw plus I think with charging losses (for example, on the Prologue there's always some sort of fan running when charging, even when it's cold outside), the efficiency of charging will be much better!

The big pain is dealing with thick wires, especially something like 6 AWG four wire for 14-50. I'm guessing 6-20 is a lot cheaper/easier to install because it can be safely wired with 12/3 Romex.
 
Not in a 6-20R though. I think it's just 14-50 with EV-specific versions, which can provide Level 2 charging - typically 32A at 240V.

I did find that there are some 6-20 duplex receptacles. Leviton has them in standard oval and Decora.

5822-W_610x_crop_center.png


But most are single: mostly round requiring a special plate.

5461-W
Yes, it was the big ones. I assume they were intended for use in more continuous duty scenarios.

I have a 6-20/5-15 duplex in my shop. Love it. Very convenient. I also have an L14-20P that I split as a mwbc or feed lower draw 240 loads.

IMG_0001.webp
IMG_0002.webp


I don’t know what is considered continuous duty for the duplex, and what could cause overheating, but I would suspect that the locking plugs, intended for generators, are designed for continuous duty.

If a major concern, one could also always upgrade the conductor feeding the receptacle. 10ga would go into the duplex fine, and would have marginally lower losses. Not that the screw terminals or conductor is necessarily the culprit, but it’s another source of failure.
 
Hi, currently at home we charge with level 1 through a regular wall outlet. I would like to improve the charging situation at home, now that I'm selling the Bolt and the Prologue will be my only vehicle. When I had the Bolt and Prologue I could charge one and drive the other LOL.

Our home is older and rented so I'm trying to keep the costs low on this, that's why I'm not going with a 14-50 outlet/circuit. If I wanted that the whole house would need to be upgraded or something.

My question is, if I have a professional electrician install a Nema 6-20P outlet in the garage (with landlords permission of course) do those suffer from the same problems as the "cheap" 14-50 outlets where they melt after a few months? I would be using a Schumacher SC1455 charger which can do 16A at 240V using this type of outlet.

The reason I am willing to spend a little bit of money on this is we pretty much are always charging 24/7 with the current setup. If I don't charge during peak times, well, I don't think the car would ever charge. With the L2 charging, even at 16A, we could change our PG&E rate plan to the EV one where night time is quite a bit cheaper and only charge at those times.
I've been using a 6-15 for 16 amp charging since 2019.
I easily get by using a 12 amp 240v charger for charging overnight.
 
I have a 6-20 in my garage, charge my Prius Prime with it.

The PP EVSE "guts" and car's onboard charger tolerate and accept 240V/16A like you'd find overseas.

So I made a homebrew adapter from the 6-20 to a normie 120 outlet, albeit industrial grade.

Garage already had a sub panel for a welder outlet so the whole project was super easy and cheap. Regular 12 gauge Romex with the white taped red.

Also got a "4000 watt" (really 3600-ish) heater to make additional use of the outlet.
 
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The big pain is dealing with thick wires, especially something like 6 AWG four wire for 14-50. I'm guessing 6-20 is a lot cheaper/easier to install because it can be safely wired with 12/3 Romex.
Wire the EVSE direct and use only two big 6 AWG and one 8 AWG for ground. The EVSE doesn't use neutral.
 
I’d request a Hubbell brand outlet be installed. It’ll cost a little more, but they are top quality.

16 amp draw with the continuous load calculation is 20 amps so #12 wire is fine to use, but #10 wouldn’t hurt either. How far will It be from the panel?
 
I’d request a Hubbell brand outlet be installed. It’ll cost a little more, but they are top quality.

16 amp draw with the continuous load calculation is 20 amps so #12 wire is fine to use, but #10 wouldn’t hurt either. How far will It be from the panel?
Yes when a 2.5% voltage drop occurs, go to the next size bigger wire.
 
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