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Gen 2 charger ground faults

ccdisce

EBISU like
Sep 10, 2014
226
97
Georgia USA
HPWC Installation Guide/Manual recommends on Pg8

<<Caution: The two phases used must each measure 120V to neutral. Earth ground must be connected to neutral at only one point, usually at the breaker panel.>>
 

SeminoleFSU

Voluntaryist
Apr 5, 2013
1,453
359
Atlanta, GA
I just got the single red T flashing on gen2 charger today for the first time. Here's my story:
Purchased a 2013 P85 in Oct 2013. No problems charging on a 14-50 plug at my old house or new one for 5yrs.
Get a loaner P100D MX, bring it home... Won't charge using my gen1 charger. Starts to charge, but the breaker flips as it goes through its test. I call customer support and I want to say they walk me through a procedure (this was months ago so I can't remember what that procedure was) and it starts working.
Turn the MX loaner back in, months go by no issues with my p85 on its gen1 charger.
Then I get a MS P100D loaner, bring it home to charge... Same issue. Call customer support. They have me shut down / power off the car. Try to charge. Breaker flips before amps ramp up. Never could get it to charge at my new house. Keep in mind new house has TWO 14-50 plugs one that gets used the other not used at all. Both plugs same behavior. Breaker flips when charging begins before amps ramp up (during it's testing cycle). P100D MS loaner came with gen2 changer. Try it. Same behavior on both plugs... Breaker pops.
Turn that one back in and was never able to get it to charge on either plug using original gen1 or new gen2 charger... Sell my 2013 p85.
Fast forward few more months... 100D loaner i'm thinking about buying. Same problem. This time I decide to research.... Stumble on some threads saying that GFCI breakers can be the issue?? Um, why would all the sudden BOTH plugs have the same issue, particularly considering the theory on these threads is that the GRCI breaker is wearing out and going bad. Well, they are only two years old and one was never used.. both flipping? Hmmm... my electrician comes out and we swap one of the reakers to the original 50a breaker without GFCI... 100D charges like a champ several days no issues... Get home today... Blinking red T on mobile connector. Red light on charge port. I'm thinking... Well this is new. breaker hasn't tripped I still have power but it isn't happy. Dash screen gives some type of message that makes me wonder if I should unplug the gen2 charger and replug and try again. So I unplug from car, unplug gen2 charger from 14-50, wait 10 secs, plug it back into the socket, connect to car... Viola. Happy again. WTF?

One thing I can say with pretty strong certainty: when Tesla was on the old onboard single 40a or dual 40a (total of 80a) inverters, I never had any issues. When they went to the new onboard 32/72a chargers, those go through some type of ground or some extra safety check that causes GFCI breakers to trip. Whether that is related to the ground fault error I saw tonight on the gen2 connector where one T blinks red, I don't know... But I suspect they might be.

Long story short, the only way I can charge my new 100D is by using a non-GFCI breaker which is very dangerous in a carport that routinely gets wet... And it's not up to code either. I'd call customer support and try to talk to them about it but I haven't been able to get anyone to actually ANSWER THE PHONE even after calling 3-4x and waiting for OVER AN HOUR before finally giving up. No exaggerating. One of those times it said my hold time would be "over 5 mins"... I waited for 78m exactly before hanging up because I need to go to bed. Unfrigginreal
 
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eprosenx

Active Member
May 30, 2018
2,065
2,485
Beaverton, OR
I just got the single red T flashing on gen2 charger today for the first time. Here's my story:
Purchased a 2013 P85 in Oct 2013. No problems charging on a 14-50 plug at my old house or new one for 5yrs.
Get a loaner P100D MX, bring it home... Won't charge using my gen1 charger. Starts to charge, but the breaker flips as it goes through its test. I call customer support and I want to say they walk me through a procedure (this was months ago so I can't remember what that procedure was) and it starts working.
Turn the MX loaner back in, months go by no issues with my p85 on its gen1 charger.
Then I get a MS P100D loaner, bring it home to charge... Same issue. Call customer support. They have me shut down / power off the car. Try to charge. Breaker flips before amps ramp up. Never could get it to charge at my new house. Keep in mind new house has TWO 14-50 plugs one that gets used the other not used at all. Both plugs same behavior. Breaker flips when charging begins before amps ramp up (during it's testing cycle). P100D MS loaner came with gen2 changer. Try it. Same behavior on both plugs... Breaker pops.
Turn that one back in and was never able to get it to charge on either plug using original gen1 or new gen2 charger... Sell my 2013 p85.
Fast forward few more months... 100D loaner i'm thinking about buying. Same problem. This time I decide to research.... Stumble on some threads saying that GFCI breakers can be the issue?? Um, why would all the sudden BOTH plugs have the same issue, particularly considering the theory on these threads is that the GRCI breaker is wearing out and going bad. Well, they are only two years old and one was never used.. both flipping? Hmmm... my electrician comes out and we swap one of the reakers to the original 50a breaker without GFCI... 100D charges like a champ several days no issues... Get home today... Blinking red T on mobile connector. Red light on charge port. I'm thinking... Well this is new. breaker hasn't tripped I still have power but it isn't happy. Dash screen gives some type of message that makes me wonder if I should unplug the gen2 charger and replug and try again. So I unplug from car, unplug gen2 charger from 14-50, wait 10 secs, plug it back into the socket, connect to car... Viola. Happy again. WTF?

One thing I can say with pretty strong certainty: when Tesla was on the old onboard single 40a or dual 40a (total of 80a) inverters, I never had any issues. When they went to the new onboard 32/72a chargers, those go through some type of ground or some extra safety check that causes GFCI breakers to trip. Whether that is related to the ground fault error I saw tonight on the gen2 connector where one T blinks red, I don't know... But I suspect they might be.

Long story short, the only way I can charge my new 100D is by using a non-GFCI breaker which is very dangerous in a carport that routinely gets wet... And it's not up to code either. I'd call customer support and try to talk to them about it but I haven't been able to get anyone to actually ANSWER THE PHONE even after calling 3-4x and waiting for OVER AN HOUR before finally giving up. No exaggerating. One of those times it said my hold time would be "over 5 mins"... I waited for 78m exactly before hanging up because I need to go to bed. Unfrigginreal

So the flashing red T sounds like a different error condition from the blowing of the GFCI. Have you looked up the error code in the UMC manual? (I am not at a computer)

On the GFCI breaker: It may be expensive, but I might try a new model of GFCI breaker (or at least a new unit even if it is the same model).

We have heard about these issues on the forums in the past (mostly on standard 20a 120v receptacles) and the solution has generally been to replace the GFCI or even swap it to a different brand (obviously with a circuit breaker that is hard since you need one rated for the panel).

FWIW, GFCI units have a massive failure rate. Apparently they can be damaged by surges caused by lightning, etc (or maybe that has nothing to do with your situation).

Also, I think under the US NEC I don’t think I you need a gfci breaker still for 14-50 receptacles for RV’s as long as they are in a weatherproof outdoor box as far as I know. I do think that GFCI is a good idea if your UMC is in a wet location though.
 
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SeminoleFSU

Voluntaryist
Apr 5, 2013
1,453
359
Atlanta, GA
So the flashing red T sounds like a different error condition from the blowing of the GFCI. Have you looked up the error code in the UMC manual? (I am not at a computer)

On the GFCI breaker: It may be expensive, but I might try a new model of GFCI breaker (or at least a new unit even if it is the same model).

We have heard about these issues on the forums in the past (mostly on standard 20a 120v receptacles) and the solution has generally been to replace the GFCI or even swap it to a different brand (obviously with a circuit breaker that is hard since you need one rated for the panel).

FWIW, GFCI units have a massive failure rate. Apparently they can be damaged by surges caused by lightning, etc (or maybe that has nothing to do with your situation).

Also, I think under the US NEC I don’t think I you need a gfci breaker still for 14-50 receptacles for RV’s as long as they are in a weatherproof outdoor box as far as I know. I do think that GFCI is a good idea if your UMC is in a wet location though.
I had my old 2013 p85 and the new 2018 100D here at the same time. 2013 charged fine with gen1 charger on both GFCI protected plugs. 2018 wouldn't on either plug using both gen1 and gen2 connectors. Flipped the breaker every time like all the other loaners I had with the new 32/72a on board inverter... The GFCI problem seems to be inverter related. I have a GE panel.. need to look some more but wasn't sure which GFCI breakers would be compatible and didn't want to buy another of the same exact model (also GE) so right now I'm using the one outlet without GFCI and no issues.
As for the red T, the more I read the more I think the 14-50 adapter was slipping out just slightly from the connector itself.. considering one of those brackets to take the weight off the dongle if it happens again
 
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eprosenx

Active Member
May 30, 2018
2,065
2,485
Beaverton, OR
I had my old 2013 p85 and the new 2018 100D here at the same time. 2013 charged fine with gen1 charger on both GFCI protected plugs. 2018 wouldn't on either plug using both gen1 and gen2 connectors. Flipped the breaker every time like all the other loaners I had with the new 32/72a on board inverter... The GFCI problem seems to be inverter related. I have a GE panel.. need to look some more but wasn't sure which GFCI breakers would be compatible and didn't want to buy another of the same exact model (also GE) so right now I'm using the one outlet without GFCI and no issues.
As for the red T, the more I read the more I think the 14-50 adapter was slipping out just slightly from the connector itself.. considering one of those brackets to take the weight off the dongle if it happens again

Yes, I think you are completely right on it being inverter related. Great job on the fault isolation testing!

So I have heard that some devices can cause interference that mess with GFCI's and can cause them to trip. We have heard this enough in the forums that clearly Tesla has some kind of an issue here. I wonder if this will become a much more serious issue when a lot more people end up with GFCI breakers on 50a circuits. Right now I think the vast majority don't have them. The requirement was only added to the 2017 NEC in Article 625 and it can take jurisdictions time to adopt the new code. Also, some places like Oregon have struck a lot of the new NEC code requirements as they think they are too expensively onerous for the cost. Sadly, they missed the Article 625 requirement as it snuck through as an emergency change, so Oregon did adopt it. :-(

I would push this issue with Tesla since you are a poster child case with a great ability to test.

But if you really want the GFCI protection then your only option is to try a new breaker (even if it is the same model). You might also check out the Eaton breakers as they spend $$$ to cross rate them into many other manufacturers panels and so perhaps that might work better (check the rating to be sure).

P.S. Note also that the UMC has a built in GFCI, so really the only risk is the connection from the receptacle to the UMC. Downstream of the UMC is protected by the GFCI in the UMC.

P.P.S. You also could solve this by simply installing a Wall Connector without a GFCI breaker. GFCI breaker is not required for the hard wired Wall Connector since the Wall Connector has one built in. There are also a lot of other benefits to the Wall Connector (especially for outdoor installations).
 
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SeminoleFSU

Voluntaryist
Apr 5, 2013
1,453
359
Atlanta, GA
Yes, I think you are completely right on it being inverter related. Great job on the fault isolation testing!

So I have heard that some devices can cause interference that mess with GFCI's and can cause them to trip. We have heard this enough in the forums that clearly Tesla has some kind of an issue here. I wonder if this will become a much more serious issue when a lot more people end up with GFCI breakers on 50a circuits. Right now I think the vast majority don't have them. The requirement was only added to the 2017 NEC in Article 625 and it can take jurisdictions time to adopt the new code. Also, some places like Oregon have struck a lot of the new NEC code requirements as they think they are too expensively onerous for the cost. Sadly, they missed the Article 625 requirement as it snuck through as an emergency change, so Oregon did adopt it. :-(

I would push this issue with Tesla since you are a poster child case with a great ability to test.

But if you really want the GFCI protection then your only option is to try a new breaker (even if it is the same model). You might also check out the Eaton breakers as they spend $$$ to cross rate them into many other manufacturers panels and so perhaps that might work better (check the rating to be sure).

P.S. Note also that the UMC has a built in GFCI, so really the only risk is the connection from the receptacle to the UMC. Downstream of the UMC is protected by the GFCI in the UMC.

P.P.S. You also could solve this by simply installing a Wall Connector without a GFCI breaker. GFCI breaker is not required for the hard wired Wall Connector since the Wall Connector has one built in. There are also a lot of other benefits to the Wall Connector (especially for outdoor installations).
I'm going to sign paperwork and take "delivery" of the 100d service loaner this afternoon so I'll definitely bring it up to them today. Yeah other ppl have mentioned there is built in GFCI on the chargers the danger is the outlet not the charger. That made my electrician feel better especially when I told him I only unplug and take the mobile connector with me on road trips. Someone else also mentioned the HPWC eliminates the problem.. I have looked on eBay and you can pick them up for 4-500ish. Just having a hard time justifying it since I can't get 72amp charging since I only ran enough wire to do two 50a plugs and the run was a royal pain and mostly possible because we had the house down to the studs... One other thing I could do is buy a 2nd mobile charger and just leave it plugged in. :p
 

eprosenx

Active Member
May 30, 2018
2,065
2,485
Beaverton, OR
I'm going to sign paperwork and take "delivery" of the 100d service loaner this afternoon so I'll definitely bring it up to them today. Yeah other ppl have mentioned there is built in GFCI on the chargers the danger is the outlet not the charger. That made my electrician feel better especially when I told him I only unplug and take the mobile connector with me on road trips. Someone else also mentioned the HPWC eliminates the problem.. I have looked on eBay and you can pick them up for 4-500ish. Just having a hard time justifying it since I can't get 72amp charging since I only ran enough wire to do two 50a plugs and the run was a royal pain and mostly possible because we had the house down to the studs... One other thing I could do is buy a 2nd mobile charger and just leave it plugged in. :p

Wall Connector units are only $500 direct from Tesla, so unless you get a really good deal on eBay I would probably go direct.

What size wire is run to your garage? Is it in conduit all the way? Or just romex?

Depending on what kind of wire it is and how much capacity you have in your panel, you might be able to up to a 60a breaker for instance. Also if it was in conduit the whole way you might be able to swap the wire out less expensively. If you thought you might some day have two Tesla's you could get two Wall Connectors and say have them share a single 100a circuit. Then either one could put out the full load or they could share it if two cars needed to charge at once.

But yeah, no GFCI breaker needed with a Wall Connector.

I also think that if properly weatherproofed and not inserted/removed in the rain then a Wall Connector connection to a non-GFCI receptacle is not all that dangerous. Folks have been plugging into RV parks for decades without GFCI...
 

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