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UMC Won't Charge at 240, but will on 110

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About a week ago, I had a panel change at the house. That night, the Tesla wouldn't charge.
I called the electrician, and he showed up the next morning and opened the outlet to see if anything looked wrong. He then, closed it up and viola! The car began charging again. He said that he had really not done anything, but there you go...

Fast forward 4 days and on Saturday, the car charged in the morning, came back after errands and refused to charge again.
UMC Shows top green light and flashes red small LED 4 times, sometimes 3... Called Tesla service and they say that it's electrical... Car charged at a charge point charger, and will *sometimes* charge at home..

Today, it charged over night and was at full charge in the morning, but now won't charge at all... This time ONLY a red light on the UMC, and the Red Ring on the charging port. Won't charge at all.
Will charge on 110 though.

Now my electrician says that the outlet is setup correctly (there wasn't anything done to the outlet, which has been in service since 2014). The panel change happened before the sub-panel which has my 50 AMP GFI circuit that feeds an inside and outside NEMA14-50.

According to the electrician, the outlet couldn't have a ground fault as indicated by the warning LEDs because the GFI wouldn't allow the circuit to be closed.

Does this sound correct? Could it just be the 220 Plug adapter that is bad?

Thanks for your advice, I am headed to the local Service Center to have them test out the UMC and probably swap it for a new one.
 
I'm sure FlasherZ will chime in here in due time, but my guess is it's the GFCI that's causing the problem. Something in the back of my brain is saying you're not supposed to wire two GFCIs in series, and I think the UMC has it's own mechanism. Why changing the panel would cause the problem now .. probably something changed with the ground. I'll now step aside and allow those that know what they're talking about to chime in. :)
 
I vote bad connection either to the outlet or inside the outlet since that's what he moved around to "fix" it. Also if the ground connection to the outlet was bad, I don't see how a GFI back at the panel would detect it...after all the ground is probably just fine there.
 
Thanks for the advice...
I am super appreciative of the help and advice, I needn't tell you all how uneasy it feels getting home (which I have always felt as the save zone), only to find I can't charge...

I'm sure FlasherZ will chime in here in due time, but my guess is it's the GFCI that's causing the problem. Something in the back of my brain is saying you're not supposed to wire two GFCIs in series, and I think the UMC has it's own mechanism. Why changing the panel would cause the problem now .. probably something changed with the ground. I'll now step aside and allow those that know what they're talking about to chime in. :)

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Thanks Dave,
I will be sure to let them know that the UMC has its own GFCI, maybe they could just swap out the 50 AMP GFCI Breaker with a standard breaker?...

I vote bad connection either to the outlet or inside the outlet since that's what he moved around to "fix" it. Also if the ground connection to the outlet was bad, I don't see how a GFI back at the panel would detect it...after all the ground is probably just fine there.
 
According to the electrician, the outlet couldn't have a ground fault as indicated by the warning LEDs because the GFI wouldn't allow the circuit to be closed.

This is semi-correct. It's true that it won't have a true "ground fault" as in current being sunk to the grounding conductor. However, the Tesla UMC checks to ensure that the voltage between the line conductors and ground remains steady - in essence, checking for a good ground. That sounds like your problem. Have him ensure the panel is grounded correctly.

I did see this problem on a receptacle that had bad ground pins. The two spring pins inside the receptacle that were supposed to "hug" the ground pin in the plug were bent and couldn't form a good connection. Turning the power off, opening the receptacle, and bending the pins closer together for a better connection solved the problem.

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This ... 2 GFCI in series will randomly cut the current.

GFCI on NEMA 14-50 | Forums | Tesla Motors

Years ago that was the case, but today's GFI's don't fall to this problem.

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I will be sure to let them know that the UMC has its own GFCI, maybe they could just swap out the 50 AMP GFCI Breaker with a standard breaker?...

This would indeed be legal. Code doesn't require GFI on this particular type of circuit (yet).
 
Okay, the saga continues...

Got home around 5, electrician had outlet apart and tightened all ground, the conduit which acts as ground and had the sub box apart, obviously in the middle of checking the GFCI breaker... He tightened and checked, re-checked everything. Plugged the car in, BOOM! Green! Yay Problem solved, right... Not so fast...

I left and drove for approx 20 miles, 30 miles of range, came back and plugged in... Could not charge.
Moved my car OUTSIDE the garage and plugged back in, could charge (WFT?)
Moved the car back inside the garage got RED light on charger... But the car charged!...
Lost my Sh!t and called the electrician... Installing the HPWC on a 100 AMP service.
Electrician will re-run the existing 50 AMP Service so that I have backup outlets...

Will let you know how this continues...
..
 
You should ask him one more question: did he check just the wiring, or did he also tighten the ground prongs of the receptacle itself (push them inwards so they'll grab the plug better)? That's what happened on a couple of Levitons (most common receptacle) that I've seen.
 
And if it's a ground problem not in the receptacle, the HPWC is likely to have the same problem, I would think.

Yeah, thought did cross my mind. Electrician said that maybe there's an intermittent problem with the neutral from the pole... Our power here on Long Island is pretty crappy from what I hear, and there are times there isn't a good neutral, but you don't really notice, until you have something demanding like a Tesla to charge. :-(

I will keep you updated. I'm hopeful the new line and new wire will correct the situation. As it is right now, my UMC refuses to charge on the NEMA 14-50, but does on 110, albeit at 2 MPH! (12 Amps) Ugh!

Fortunately tomorrow for work I am driving towards 2 separate superchargers. I can do my work, drive about 10 miles and hit the supercharger and then head back. just makes for an, er, exciting​ existence....
 
Okay,
So today, the electrician ran new wire for the 50 AMP circuit to the 220 NEMA 15-40.
Also, I had purchased the High-Power Wall Charger.

Today the car charged every possible way...
It was slowly charged overnight on a 110/12 at 3 MPH (awesome... not!)
Then I charged at a supercharger.
Got home, tested the NEMA 15-40, which works now
Finally charging now on the HPWC at 57 MPH 79 AMP.

I am told the HPWC doesn't have a neutral, so if I'm having a problem with the neutral from the pole, then it should still prove reliable, but when they re-ran the cables to the outlet, the ran a ground back to the panel so that the conduit didn't have to be ground. Hopefully this is put away for good!

Thanks to all with advice and terminology so I could speak somewhat intelligently!
 
I called back when I installed in 2013, and LIPA (now PSEG) didn't offer. I have also since installed Solar, so I had to give up balanced billing... Maybe I could do that now. Probably would make sense to just have the HPWC start at midnight and charger for an hour or 2 vs. the UMC taking 3.5-5 hours depending on my SOC when I return. ( I have a very irregular "commute")

I will check, thanks for the thought...
 
Personally, I'd always run a dedicated ground wire and never trust the conduit as a ground. I've heard too many stories about EMT clamps coming loose.

If assembled properly with bonding bushings and the right type of screws, they don't. The problem is that there are a lot of installations done without knowledge of proper EMT technique. For example, they lose the set screw for the fitting and just pick any other stove bolt (or worse yet, I've seen people use wood screws!!), or they just make the EMT lock-nuts finger tight/ram them with a screwdriver instead of using the proper lock nut wrench.

(I see very few DIY'ers with this needed tool or its equivalent: Channellock 960 1/2-Inch to 1-1/2-Inch Electrical Locknut Plier - Chanellock Electrical Pliers - Amazon.com )

That said, I also know plenty of electricians who don't trust EMT either - or who avoid EMT altogether (preferring PVC), and run ground wire. You can trust IMC and rigid without concern.