GFCI for 220v garage receptacle.

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nietzj said:
Just curious, watched a couple charger install videos and am wondering why people are using Romex 6/3 when the chargers only need 2 hots and a ground, I was planning to use 6 gauge 6/2 with a #12 ground On a 60 amp breaker . One guy terminated the white wire in the panel and put a wire nut on the wire in the charger unit, not a lot of spare room to start with. Why are people using 6/3 with the extra unused neutral? I’ve never hooked one up, am I missing something, maybe for future use for a different charger that needs 120/240?
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Because a NEMA-14 has become the commonplace receptacle for these things when they are cord-and-plug connected. I think that's because the NEMA-14/50 is what you find in full hook-up RV parks, so they can bring their charger with them and recharge at an RV park.
 
After sleeping on this I came up with a new plan. Cut the sheet rock channel in a 3/4 metallic flex, pull in 2 #6’s and a #10 ground, (THHN) install a 60amp regular breaker. Then spend the rest of the weekend repairing sheet rock and painting. It’s more work but it will look perfect when done and most of all code compliant. #6 THHN @ 75degree is rated for 65amps. Plus with a raceway if the charger requirements change there’s some flexibility to add a neutral. 3/4” flex up to (4) #6’s
 
Long story, been an electrician for 40 years, know every trick in the book for a clean install, had a stroke a few years ago and I’m extremely limited on what I can now do, basically picture what you could do one handed and with no balance. So anything above 5 feet is not an option. My wife helps as a second hand when needed but far from ideal. I get by best I can but there are no simple tasks anymore.
 
No problem, if I could climb a ladder I could easily fish in 6ft of flex from the panel to a recessed box, add an extension, pipe over next to the ceiling and down to around 5ft. buy a cheap can of spray paint and spray the conduit white to match the wall before installing, pull wire, terminate, done. That’s how the old me would have done it. Clean as possible without wall damage.
 
Fred B said:
some charger mfg actually recommend against gfci as it sometimes will conflict with the charger and create nuisance tripping. Direct wire eliminates this issue, and the charger is required to be gf protected on IT'S outlet anyway.
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To put a little background on this, some EVSEs use sophisticated ground connection validation. A typical scheme involves putting intermittent pulses of current through the ground to check the characteristics, e.g. resistance and impedance. While these pulses are below the nominal trip current, the sharp edges or specific pattern can look like high current leakage, triggering an upstream GFCI to trip.
 
nietzj said:
After sleeping on this I came up with a new plan. Cut the sheet rock channel in a 3/4 metallic flex, pull in 2 #6’s and a #10 ground, (THHN) install a 60amp regular breaker. Then spend the rest of the weekend repairing sheet rock and painting. It’s more work but it will look perfect when done and most of all code compliant. #6 THHN @ 75degree is rated for 65amps. Plus with a raceway if the charger requirements change there’s some flexibility to add a neutral. 3/4” flex up to (4) #6’s
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Can you order some 6-2 mc it's not as expensive as it could be and may be easier for you vs trying to pull in conductors into flex.

Check out "wire and cable your way" they do smaller cuts for not a bad homeowner price.
 
TheCats said:
To put a little background on this, some EVSEs use sophisticated ground connection validation. A typical scheme involves putting intermittent pulses of current through the ground to check the characteristics, e.g. resistance and impedance. While these pulses are below the nominal trip current, the sharp edges or specific pattern can look like high current leakage, triggering an upstream GFCI to trip.
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No type of pulse on an EGC should cause a GFCI to trip.
 
Thank you for your suggestion, I appreciate it. I made a quick sketch and if I'm careful I should be able to remove the rock in one section and reuse it. It's really not too bad to bad. While I'm at it I plan to drag a 12/2 along and add a receptacle in a better spot for plugging in a vacuum. With the wall open I might just use 3/4' pvc instead of the 6/3 cable in the sketch which isn't code compliant. It will all work out.
 

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nietzj said:
This would be installed in the next couple weeks so it would be under the 2020 NEC. I did reach out to another electrician in Minnesota and he said he's put 5 in recently and the inspector did not require GFCI protection, I just wanted to double check.
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Minnestoa is now on 2023. Or was the permit opened before 2023 adoption?
 
retirede said:
If you install a $20 14-50R, chances are you’ll be back within a year to replace it after it melts.

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A Hubbel or Bryant quality receptacle is close to $100.
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I think Zoro has the Bryant for like $50.
 
If you install a $20 14-50R, chances are you’ll be back within a year to replace it after it melts.
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Crazy question but how in Hades are these cheaper 14/50 even for sale if they are such a fire hazard? I assume they are Labeled/Listed.
 
I have no doubt that with the steady 48amp draw for 6-8 hours and a loose connection this will heat up and cause damage. Knowing these receptacles are now commonly used for EV charging I would think that might cause manufacturers to add some sort of rating or disclaimer for prolonged use besides the continuous duty. I'm surprised Square D has a $10 rec as well, they used to be the standard for quality.
 

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nietzj said:
Crazy question but how in Hades are these cheaper 14/50 even for sale if they are such a fire hazard? I assume they are Labeled/Listed.
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I believe they are only tested to carry 40 amps continuously.
Keep in mind 210.21(B)(1) A single receptacle installed on an individual branch circuit shall have an ampere rating not less than that of the branch circuit. And the calculated branch circuit rating for a EV charger with a 48A nameplate is 60 Amps, becasue the charger is a continuous load.

Why not just use the correct NEMA 6-50 receptacle if the charger nameplate is '240' Volt and can be set to charge at 40 amps?
I believe you can adjust the charging amps in the settings in the charger, I set them to no pull more than 40A thru a 50A receptacle and 6/2 NM cable.


nietzj said:
I have no doubt that with the steady 48amp draw for 6-8 hours and a loose connection this will heat up and cause damage.
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No doubt a 48A continuous load would melt a 50A receptacle and I suspect that is what all those posts on social media are about.
I have not seen any of the electricians on here post that a receptacle they personally installed melted down.
When I had to hook up several cord connected 48 Amp loads (not EV chargers but refrigerated container parking spots) I used 60A 'pin and sleeve' type receptacles for that. They have been in service for years now without issue.
Since that is impractical for a residence a 48A charger should be hard wired.
 
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