Home charger failure

[jlghertner]

Electrical advice needed.
Tesla charger installed by electrician when I bought AWD LR. About once a month the breaker would trip then it fried. Electrician said it was a faulty breaker; ok, I caught it before my house burned down (it was too hot to touch )

with replaced breaker no further problems until recently when charger just stops working with red light. Reset button did nothing. I would cycle the breaker and all was well. Now it has done the same thing twice over the past week. Reset button does nothing. I just realized I could remove the charger and it would reset itself and work again.
But that is not a long term solution of walking out to my car for a road trip with a low battery.
Any suggestions please.

 

[eprosenx]

Electrical advice needed.
Tesla charger installed by electrician when I bought AWD LR. About once a month the breaker would trip then it fried. Electrician said it was a faulty breaker; ok, I caught it before my house burned down (it was too hot to touch )

with replaced breaker no further problems until recently when charger just stops working with red light. Reset button did nothing. I would cycle the breaker and all was well. Now it has done the same thing twice over the past week. Reset button does nothing. I just realized I could remove the charger and it would reset itself and work again.
But that is not a long term solution of walking out to my car for a road trip with a low battery.
Any suggestions please.

It sounds like they did not properly torque the wires into the breaker which is what caused it to overheat.

My fear now is that they also did not properly torque the connectors into the wall connector itself. I would open up the wall connector and inspect the wires to see if they are melted. I would check the torque on them even if they don’t look melted.

If they were not torqued properly there is a good chance it will have destroyed the Wall Connector. :-(

The good news is that the Tesla has lots of safety features that likely keep this from being a fire. It is possible that a heat sensor in the wall connector is what keeps shutting it off.

 

[jlghertner]

great suggestion but I just opened the charger up. There are no loose connections however.

It sounds like they did not properly torque the wires into the breaker which is what caused it to overheat.

My fear now is that they also did not properly torque the connectors into the wall connector itself. I would open up the wall connector and inspect the wires to see if they are melted. I would check the torque on them even if they don’t look melted.

If they were not torqued properly there is a good chance it will have destroyed the Wall Connector. :-(

The good news is that the Tesla has lots of safety features that likely keep this from being a fire. It is possible that a heat sensor in the wall connector is what keeps shutting it off.

 

[GtiMart]

What gauge wire do you have, and how is the wall charger set? I mean the max amps it's allowed to pull. Maybe you pull too much for the wire or breaker you have?

 

[Sophias_dad]

I'm with GtiMart. I'm betting they didn't size the wire/breaker correctly. Get the wire gauge, breaker rating, and how much your HPWC is rated to draw. Also, is the wire in conduit(not likely to affect breaker trips, but interesting data)? How long is the run from the panel to the HPWC?

You might be surprised at how tight the connections need to be. Additionally a common problem is that improper stripping/insertion catches some insulation under the screw or on the other side of the wire being clamped.

Another possibility is a bad connection between the breaker and the busbar its snapped onto. If the old one was >hot< it might have been arcing to the busbar and the next breaker might not have much left to connect to.

 

[jlghertner]

the wire gauge appears to be the same size as the internal wiring from the internal bus bar mounting bracket into the charger itself. The wires run through conduit. The whole thing is set as per the manual set for 40 amps to my recollection.

I will check the bus bar and the breaker connections next. Thanks.

I'm with GtiMart. I'm betting they didn't size the wire/breaker correctly. Get the wire gauge, breaker rating, and how much your HPWC is rated to draw. Also, is the wire in conduit(not likely to affect breaker trips, but interesting data)? How long is the run from the panel to the HPWC?

You might be surprised at how tight the connections need to be. Additionally a common problem is that improper stripping/insertion catches some insulation under the screw or on the other side of the wire being clamped.

Another possibility is a bad connection between the breaker and the busbar its snapped onto. If the old one was >hot< it might have been arcing to the busbar and the next breaker might not have much left to connect to.

 

[GtiMart]

What breaker do you have installed (amps)? How many amps does the car pull when charging? After an hour of charging, does the wire become hot or just warm?

 

[jlghertner]

50 amp breaker. Dip switches set per manual at 40 amps I think. Car display says 40 amps. Cable barely gets warm.

 

[jrweiss98020]

Any possibility of aluminum wiring and improper CBs/connectors?

 

[Scooby24]

What's the outlet model you're using?

 

[jlghertner]

What's the outlet model you're using?

I’m not sure what you mean by outlet model?

 

[jlghertner]

Any possibility of aluminum wiring and improper CBs/connectors?

No aluminum. The connectors look ok to me done by a licensed electrician (I got lazy). The wiring goes from the main box in my basement to a secondary breaker box in my garage area then to the Tesla charger.

 

[jlghertner]

I’m sorry to be so dense but I don’t understand as the Tesla charger is hardwired.

 

[lskarp]

I had a NEMA 14-50 in the past (I think it was Leviton), and it melted big time and arc'd when I removed my mobile cable form it. So I switched to the Wall Charger and I am very happy for it, even though it was $500 (I installed myself). The sockets work loose over time. I dont think they are really made for plugging and unplugging as I was doing 3-4 times per week!

Anyway, since then, I have been fine. I would ensurer you have the correct gauge wire for the distance and that the dip switch is adjusted properly which it sounds like you have it at 40. Maybe turn it down to 30 unless you need it to charge at that speed. I figure that I usually am at lest 10-12 hours between driving and arriving home from work and I only drive 30-50 per day. At 30 amps, you are looking at an hour or 2 to charge MY car. You may be in a different situation. But there is a chart in the install manual with the distances, gauges, and amps. I would double check all of that.

 

[GtiMart]

Secondary breaker box... Do you have any other wires going out of that box? Anything else besides the Tesla wall charger pulling some power from that same main box breaker?

 

[jlghertner]

Just LED garage and workshop lights when the car is charging and a frig in the garage which isn’t working much as the outside temp is lower than the frig still.

 

[GtiMart]

Hum... if you have a 50A breaker in your main box, you're only allowed to pull 80% (at least where I live) so your maximum is 40A. If you're car charger is set to 40A, you're already maxing your circuit. Anything else is busting that maximum, so small might it look like. Either you remove everything else on that 50A main circuit or you lower the maximum your wall charger can pull. I'm under the impression that you have just found your problem.

 

[jlghertner]

I clearly am a poor communicator My main circuit is 200 amps. My Tesla charger is connected to a new 50 amp breaker and the dip switches are set at 40 amps. I think the suggestion to lower the charger to 30 amps is a good idea to see if it will prevent this issue of the charger shutting down.

To reiterate, the charger continues to receive power as the red warning light is on during this event. Does this not indicate that there is something ring with the charging system?

I really appreciate informed responses.

Hum... if you have a 50A breaker in your main box, you're only allowed to pull 80% (at least where I live) so your maximum is 40A. If you're car charger is set to 40A, you're already maxing your circuit. Anything else is busting that maximum, so small might it look like. Either you remove everything else on that 50A main circuit or you lower the maximum your wall charger can pull. I'm under the impression that you have just found your problem.

 

[Sophias_dad]

The wiring goes from the main box in my basement to a secondary breaker box in my garage area then to the Tesla charger.

The question from GtiMart is valid. He's asking what the breaker rating is in the main panel leading to your subpanel, and what is the breaker rating in the subpanel leading to the HPWC. If they are both 50 amps, its not to code, and may not work well(nuisance trips). Since there's other stuff on the subpanel, the main panel's breaker(and the wire!) feeding that subpanel is supposed to be rated for more than the EV load of that subpanel(times 1.25 because its a continuous load) and you have other stuff on that subpanel.

The failure you are seeing is not really an overload it seems. It might be that one leg of your subpanel supply is failing(circuit breaker overloaded) and you don't have a duplex breaker installed(either at the subpanel or the main panel), or its possible the duplex breaker has failed internally and only cut power to one leg of the 240. If you happen to have a multimeter, see if both legs are at 120v to ground after the failure. It might also be that when your refrigerator starts(only using one leg of the 240, at pretty high startup amps), the HPWC sees the temporary dip in the voltage on that leg and throws an error. If the red light is flashing, the manual will tell you what the flashes mean.

Another thing to check is that ALL connections are tight, all the way back to the main panel. Not clear you did that.

 

[gfunkdave]

Focus people. While the upstream breaker may be an issue it's not the issue the OP is asking about. He's asking what the red light on the HPWC means.

OP - which generation of the wall connector do you have? What is the red light doing? Is it solid or flashing? If flashing, how many times does it flash?