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UMC_a001 Inadequate outlet grounding

Mr.Chipperson

Member
Oct 7, 2020
42
8
Indianapolis, Indiana
My outlets are regular 5-15 slow charge style. Purchased an SR+ in December. Saw this error 3-4 times but it goes away the next day and charges as normal. The detached garage has 3 outlets, one on each wall, and they all behave the same way, making me think it isn't an outlet problem. The wiring is probably old. I had a guy from an electric company come out and do a quote for a 14-50 install, I asked if the existing wiring was a risk and he said no. I would get 14-50 but it would cost $1500-2000 because they need to run higher bandwidth lines to the garage which requires trench digging. If this error doesn't go away, what is likely the cause and can I fix it myself?
 

Frank99

Member
Apr 7, 2016
133
165
Arizona
The three outlets are likely all on the same circuit/circuit breaker. The error might indicate that the ground wire isn’t well connected between the outlets and the circuit breaker box, or isn’t well connected at the cb box. Try plugging into an outlet in, for example, the house (ok to use an extension cord, as long as it’s 10 or 12 AWG). If the Problem still occurs, you might have a faulty mobile connector, or you may have some funky house wiring going on.
 

Mr.Chipperson

Member
Oct 7, 2020
42
8
Indianapolis, Indiana
This error always come up when I plug in at my garage. All three outlets in my garage behave the same way. For months, it would begin charging an hour or so after I plug it in. Now, it seems to not be charging. Red blinking light on the mobile charging cable thing. Error code is umc_a001 inadequate outlet grounding.

My question is, would an electrician know how to solve this issue without charging my thousands to upgrade everything? I know my quotes for getting a lvl 2 outlet installed for higher because they need to dig a trench to get more bandwidth to my garage.

My issue is not the charging speed though. I am perfectly happy with 110v because I drive only 20 miles a day typically. I just need this ground bs to be fixed.
 

Frank99

Member
Apr 7, 2016
133
165
Arizona
Yes, the electrician should charge a reasonable amount. They'll pull the outlets in the garage out of the wall, and check the ground connection on each, and they'll open the circuit breaker box and try to determine which ground wire goes to the garage, and check how well it's connected. It shouldn't take more than about 15 minutes if the faulty connection is in one of those places. If it's difficult to find, it could take an hour or more. No need to make signicant changes to anything.
 

Dmagyar

Member
Aug 9, 2018
319
197
Rocklin, Ca. 95765
You mention trenching to get larger wiring (not higher bandwidth) installed from the house supply?, that may be the problem you’re experiencing and it may take replacement of the existing wiring to remedy the problem as the condition of those underground wires may be at fault...
As to what you’ll be charged, theres no easy/inexpensive fix to alleviate faulty wiring, installed with or without suitable conduit underground.
 

Mr.Chipperson

Member
Oct 7, 2020
42
8
Indianapolis, Indiana
You mention trenching to get larger wiring (not higher bandwidth) installed from the house supply?, that may be the problem you’re experiencing and it may take replacement of the existing wiring to remedy the problem as the condition of those underground wires may be at fault...
As to what you’ll be charged, theres no easy/inexpensive fix to alleviate faulty wiring, installed with or without suitable conduit underground.
I don't understand how electrical systems work. The garage door opens without fail, the lights work, and my EGO battery charger always charges those batteries. The outlet used to charge my Tesla for the last 4 months. The outlets still have power too. But they don't have "ground". Isn't ground just simply a metal rod stuck in the ground and then linked to the system?
 

Dmagyar

Member
Aug 9, 2018
319
197
Rocklin, Ca. 95765
Your Tesla charger wants to keep you/occupants safe...to accomplish that it wants to see a good grounding path. It’s not the electrical system, it’s the criteria Tesla is demanding...
PS your garage door, and whatever lighting are fractional currents compared to load your car will add to the already questionable integrity of the existing circuit.
 
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