NEMA 14-50 Home Challenges

dtbaker61

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Futureproofing?

my electrician installed 6 awg for the live lines and 10 awg for the ground. Any concerns there?
if L1/L2 are 6, ground should be 8awg
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Maquis

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the picture of the breaker and L1, L2 looks ok.

Can't tell for sure on your receptacle, but the ground is undersize for sure and should be #8. Also, I do not see the L2 (blk 6AWG) at all... maybe its a bad angle since you are seeing voltage on both L1,L2 w voltmeter

The neutral is not used by chargers, but you 'should' have one running to receptacle in case you use that outlet for anything else that might require a neutral.

I suspect that the ground you have landed to the box does not have metal EMT all the way back from box to service... meaning it is not actually grounded, and for sure not grounded well with just awg12. You really need to pull #6 for L1,L2,N and #8 for ground.... all the way from service to receptacle.
#10 copper EGC is compliant per NEC table 250.122. And I believe the bare EGC runs back to the panel. The green pigtail is there to simply ground the box.
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dtbaker61

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#10 copper EGC is compliant per NEC table 250.122. And I believe the bare EGC runs back to the panel. The green pigtail is there to simply ground the box.
1642962377006.jpeg
The table you show is for bare copper grounds....
That bare ground might be 10, but is likely awg12, and goes back to Romex.... not good since it is not really bare copper any more. Sure, a ground *shouldn't* carry current, but if it did you don't want it to overheat and start a fire inside the wall. This is why there are different ampacity ratings for different size wire, with different insulations, with different 'fill % ' inside different sized of conduit conduit or in the ground, etc.

insulated copper for 50a ground should be 8AWG, one size smaller than the L1,L2 6AWG

nema 14-50 receptacles really should have 6awg L1,L2,N and 8awg insulated ground all the way back to service.


....the OP might have a bad charger, or the pigtail isn't plugged all the way in if it doesn't work on anybody elses outlet... but the fact remains that a NEMA 14-50 *should* be wired with 6awg to L1,L2,N, and 8awg for ground all the way back to service.
 
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Maquis

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The table you show is for bare copper grounds....
That bare ground might be 10, but is likely awg12, and goes back to Romex.... not good since it is not really bare copper any more.

insulated copper for 50a should be 8AWG

nema 14-50 receptacles really should have 6awg L1,L2,N and 8awg insulated ground all the way back to service.


....the OP might have a bad charger, or the pigtail isn't plugged all the way in if it doesn't work on anybody elses outlet... but the fact remains that a NEMA 14-50 *should* be wired with 6awg to L1,L2,N, and 8awg for ground all the way back to service.
I am not aware of any NEC provision that differentiates between a bare vs insulated EGC. Since it doesn’t carry current, the insulation (or lack thereof) should make no difference.
 

bruceski88

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The table you show is for bare copper grounds....
That bare ground might be 10, but is likely awg12, and goes back to Romex.... not good since it is not really bare copper any more.

insulated copper for 50a should be 8AWG

nema 14-50 receptacles really should have 6awg L1,L2,N and 8awg insulated ground all the way back to service.


....the OP might have a bad charger, or the pigtail isn't plugged all the way in if it doesn't work on anybody elses outlet... but the fact remains that a NEMA 14-50 *should* be wired with 6awg to L1,L2,N, and 8awg for ground all the way back to service.
Make sure the pigtail is pushed into the mobile charger. It needs considerable force and will make a loud click when mating properly
 


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Thank you everyone for your feedback!!!

UPDATE:

We suspect we have a defective charger. The weird thing is it works when plugged into our 120V/12A Wall Outlet but when plugged into our 240V/32A NEMA 14-50 Wall Outlet the Ford charger does not work. We ended up purchasing the JuiceBox 40 Amp level 2 charging station. We plugged it into the same 240V/32A NEMA 14-50 Wall Outlet the Ford charger did not work on and right out of the box it worked. We have been charging from the JuiceBox and have not had in any problems since. We hope the Ford 240/32A charging experience is not foretelling of what to expect with the MME performance and future maintenance.

So far, It has definitely been fun to drive and we appreciate folks double take as we ride by ?.

Thanks again for your input!

In our opinion, DEFECTIVE. We our curious has anyone plugged theirs in just to see if it works?
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Crilly

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When I ended up with 2 gtpes I got the automatic switch that switches from one charger to the next. I am using the chargers that came the mmes. They work great. Just make sure you have plug the short cable all the way into the charger.
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