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Car won’t charge on HPWCs/UMC, says check Wall Power

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I just noticed some weirdness with one of our black WCs this morning. My car was showing it was charging at a reduced rate (10 mph). I tried unplugging the cable and plugging it back in half a dozen times but it would only show the orange ring and charge slowly. I tried one of the other WCs on my car and moved my WC cable over to another car and then they both worked fine. I then plugged my WC back into my car and it worked fine. Go figure.
David, if you see this again, may want to try resetting the affected WC or all of them. (Red button, of course.) Wonder if the load balancing algorithm got hung up? Never heard of that before.....
 
David, if you see this again, may want to try resetting the affected WC or all of them. (Red button, of course.) Wonder if the load balancing algorithm got hung up? Never heard of that before.....
I will try that next time. This was on the master unit. When I swapped cables to different cars, it immediately split the charge 50/50. When I had it plugged into my car, it showed a maximum of 48 amps available but just kept showing the orange ring.
 
I will try that next time. This was on the master unit. When I swapped cables to different cars, it immediately split the charge 50/50. When I had it plugged into my car, it showed a maximum of 48 amps available but just kept showing the orange ring.
Sounds like this may be contagious.. :D But seriously, I've never had any 'ring' problems. It's always been the 'check charger power'. All very strange. (We've never had two cars at the same time, yet, still planning when to order the 3.)
 
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Sorry I meant to ask if you were getting a "Tesla" solar roof? one with there new shingles.

The UMC/HPWC thing you got going on is really odd that it would reset and start charging with no rime or reason. It is almost like there was a handshake between the charger and the car, along with some master reset to clear both. Do you have the voltage at the time of the reset? I know there on board volt meter appears to see static voltage and once the car starts charging it drops 5 volts on average. They may need to tweak there max voltage upwards, knowing it will drop once the amps start flowing. Thinking back my Fluke would read the same as the car. when we work on locomotives they warn us to use old analog meters to get a true voltage readings, knowing the digitals jump around.

It really sounds like it is the car after rereading your prior post. I have never had a HPWC issue, just the UMC.
On the solar, no, normal Tesla panels, the 315W 'solid black' ones. We just got a new roof put on because of hail damage, and I don't believe it would be cost effective (in any case) to get the solar shingles (even without the new replacement roof), and I don't have anything against panels. In 'tony' neighborhoods in California, and on top of slate or curved tile, sure.

As for this charger issue, that's what I thought all along, that the car was doing some reset or 'it's now okay, the voltage has decreased'. But yesterday AM, it was down to 240, with no luck. And, even the TeslaFi charge report shows a voltage range from 242 to 247 (from 1107 to 0131 overnight). So, not like the voltage was low all the way through.

Something is definitely resetting, and lots of it makes no sense at all.
 
Yeah, port is locked when car is locked, as you know. I've seen several threads where the car doesn't unlock when approached from the rear. Mine is in the garage and door is at the front, so, I've never had that issue. Just one more thing to verify... :D

Operator error, I walked around the car again and the unit works fine. I guess I thought the key fob was enough to release the connector.
 
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I ran into this problem over a year ago with our S P85.

Our garage has an HPWC on a 100A circuit - and a 14-50 outlet.

When the car started having charging problems on the HPWC, I tried using the UMC on the 14-50 outlet - and ran into the same charging problems - charging would not start, or if it started would stop after a few minutes.

I even tried using a 110 outlet - and had the same problem.

I called Tesla - they looked at the logs - and they believed the car's charging system was OK.

The utility ran there standard power check - and we were getting the correct voltage.

It turned out, other Tesla owners were having the same problem within several miles of our house.

After getting Tesla and the utility to talk to each other - the utility discovered problems in their distribution equipment in the area - which was introducing some noise on the power lines. It wasn't enough to disrupt most electrical devices - but was enough to prevent the Tesla chargers from operating reliably.

It took almost a week until they were able to do a trace through the grid equipment - and find the cause and repair it.

NOTE that when this happened, the normal power technicians probably don't have the equipment to test this. They had to install a special logging device on our circuit to do a more detailed analysis.

If you're seeing charging problems on both UMC and HPWC, my advice:
  • Take your car somewhere else and try to charge using your UMC or a public J1772 or destination charger. If that works, then you've probably ruled out a problem with your UMC or onboard charger(s).
  • If you know any Tesla owners in the area - check to see if they are having issues. If not, take our car over there and see if your car charges.
  • Call Tesla's phone support to have them look at the logs for your car, and see if they find any charger warnings or faults.
  • Call the nearest Tesla Service Center to see if they are having reports from any other Tesla owners in your area
While it's most likely a problem with your onboard charger(s), it's also possible you may have a problem with the power inside or outside of your house - and it may be more complicated than just verifying voltage levels.

WARNING - Tesla assured me the car's charging equipment was protected from damage due to power problems or surges. But, despite that, the secondary charger on our S P85 (which had the dual 40A chargers) blew out during this time. This was covered under our extended warranty - so it is possible for bad power to damage your onboard charger...
 
I'm experiencing the same thing with my Model S P85, tomrrow I will take my (UMC) chargers over to my friend's house and see if they car charge. I will let you know the results tomorrow. Thanks for this post.
 

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The original issue has not recurred and for reference I think it was a combination of having the TeslaFi settings and car setting such that the car never slept. Why that creates ‘power’ false positives, I got nothing. But when I reset them to defaults or opened them up, the problem disappeared. I thought I’d noted this but can’t find it above (in a thread that has gyrated a bit).

So be sure to let TeslaFi have the car sleep at night (who cares about numbers from say 10 pm to 6 am) and don’t set the Tesla settings to always connected. I believe that was the ‘bad idea’ that kept it always awake and gave it a headache. :D
 
So, the problem once again appeared THIS summer. Most of July and August, several days a week. It now seems to be when the AC is on everywhere, they pump the voltage up a bit to compensate. And it's currently doing it right now. The new interesting factor is that we have a Model 3 this year, and it does not turn up its nose at the 'bad power'. So, I went through this all again with Tesla phone support, who was useless. I thought having both cars plugged in at the same time could be of use to them in troubleshooting (while one would not charge and one was fine) but nope.

Their only suggestion was to make a Service Center appointment for the X with the issue. Went through all that rigamarole and explained everything all over again via text message to the virtual analysis people before the actual appointment, and that was also useless.

The appointment was also useless, they 'tested' things and got nowhere. Wouldn't even swap out the charger just to see. All the blather about the charge port was just that, nothing in the port that controls anything, as I though.

So even right now with that voltage (as measured by my solar inverter) at 243 volts,that is unacceptable (has been as high as 249, which I could see is a problem). Their answer was the X (and S) chargers don't have the same tolerances as the 3's. Fine, so, what? I have to live with not being able to charge for days at a time? (When the voltage drops, it takes a while for the car to 'reset', even a reboot doesnt do it (got 2019.28.3.1 yesterday, no change, of course).

Only suggestion is to call Novec (local power company) and have them look at it. Can they really turn down the voltage for a whole street or whatever?
 
Only suggestion is to call Novec (local power company) and have them look at it. Can they really turn down the voltage for a whole street or whatever?

I think they could be able to adjust it for every house on the same transformer that you are on.

We have the opposite problem where we have 5 or 6 houses all on the same 25kva transformer. Our neighbors have a pool pump that runs when we are usually charging our cars and we see the Volts drop to 220 or so. The WCs still work but they lower the Amps so we might have 3 cars sharing 44 Amps instead of 64 Amps.Tesla confirmed that the power drop is at the line where it enters our panel and is not related to the length of our wire runs from the panel. We contacted our utility and they sent a guy with a heat gun/hair dryer. He plugged it in for a minute and said it was "ok". He was testing around 5 pm when the neighbor's pool pump isn't causing the problem. I called the utility again and she said that the transformer was sized properly when it was installed. I mentioned that was probably 50 years ago. She countered that it's not their fault that we bought "smart cars" and that I could pay $10,000 for them to do a study to see if we need a larger transformer. That was last year. We gave up and will probably try asking again this year to see if we have better luck.

Anyhow, you could contact your utility and see what they say...but they might not be very helpful.
 
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I think they could be able to adjust it for every house on the same transformer that you are on.

We have the opposite problem where we have 5 or 6 houses all on the same 25kva transformer. Our neighbors have a pool pump that runs when we are usually charging our cars and we see the Volts drop to 220 or so. The WCs still work but they lower the Amps so we might have 3 cars sharing 44 Amps instead of 64 Amps.Tesla confirmed that the power drop is at the line where it enters our panel and is not related to the length of our wire runs from the panel. We contacted our utility and they sent a guy with a heat gun/hair dryer. He plugged it in for a minute and said it was "ok". He was testing around 5 pm when the neighbor's pool pump isn't causing the problem. I called the utility again and she said that the transformer was sized properly when it was installed. I mentioned that was probably 50 years ago. She countered that it's not their fault that we bought "smart cars" and that I could pay $10,000 for them to do a study to see if we need a larger transformer. That was last year. We gave up and will probably try asking again this year to see if we have better luck.

Anyhow, you could contact your utility and see what they say...but they might not be very helpful.
Thanks, David!
Interesting.... I'll give it a shot. And lol on the '50 years ago'. Good grief, people..... Let's who wins the bet I get the same response you get but instead 'we're not changing it for your high falutin' smart cars'. :D

Edit: The problem here is that dropping it may be an issue for the HVAC on the street....
 
So even right now with that voltage (as measured by my solar inverter) at 243 volts,that is unacceptable (has been as high as 249, which I could see is a problem). Their answer was the X (and S) chargers don't have the same tolerances as the 3's. Fi

The S&X chargers work up to 277 volts so that shouldn't be a problem. If it starts charging and the voltage drops that could be an issue.
 
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The S&X chargers work up to 277 volts so that shouldn't be a problem. If it starts charging and the voltage drops that could be an issue.
I have no idea what you mean, can you clarify? As we've been talking about for over a year. my car stops with 'check voltage' any time the grid is above 240-something. This whole thread was about slightly hot voltages causing issues no one can fix.

It doesn't matter the HPWC/car can be configured to run with 3 phase power, slightly hot 240 and it tells itself it's unacceptable.

Right now this is what it says: red charge port in the app (car is blue, and says the same 'check power'). I really have no idea what you are trying to add to this thread.

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I have no idea what you mean, can you clarify? As we've been talking about for over a year. my car stops with 'check voltage' any time the grid is above 240-something. This whole thread was about slightly hot voltages causing issues no one can fix.

People charge their cars on 277 volts, so 243 volts shouldn't be an issue at all. The HPWC used to officially support 277v but that they removed it from the documentation for some reason. (Though the dip switch still works and allows 277v operation.)

If the voltage is 243 volts and when it tries to charge it drops "significantly" that can trigger a check voltage warning. So it isn't necessarily the high voltage itself that is the issue.

There are really only two options I see:
  • There is a large voltage drop when the voltage is artificially high and your car starts charging.
  • You have a faulty charger.
 
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People charge their cars on 277 volts, so 243 volts shouldn't be an issue at all. The HPWC used to officially support 277v but that they removed it from the documentation for some reason. (Though the dip switch still works and allows 277v operation.)

If the voltage is 243 volts and when it tries to charge it drops "significantly" that can trigger a check voltage warning. So it isn't necessarily the high voltage itself that is the issue.

There are really only two options I see:
  • There is a large voltage drop when the voltage is artificially high and your car starts charging.
  • You have a faulty charger.
Have you read this thread at all? Tesla has checked everything. The charger is fine, and there is NO voltage drop. How can there be a voltage drop when 20 feet away at the inverter it says what it is and it's high, or fine, and the car rejects it? For the third time, Tesla says they can't do anything.
 
Only suggestion is to call Novec (local power company) and have them look at it. Can they really turn down the voltage for a whole street or whatever?

I'm on Novec also and have not had a problem since the last post above. I believe it was a software bug and was corrected by an update. Actually I was having the issue in OC Md. not here, same thing I haven't had issues there either.

Given the high heat we are suffering I wouldn't be surprised if Novec is playing with the voltage, raising it from the substation out, to reduce amperage levels. They can't play with voltage levels on a local street or individual houses, except for the A/C unit relays turning on and off to conserve power or prevent the brown out. THey are fixed taps on a transformer and would be very labor intensive. The substations I could see the possibility they could dial voltages up and down based on loads.

I'm in SR about a mile from Royal Farms if you want to come and test your car at my house. My neighbor just got a wall charger installed also. 60 Amp settings though. send me a PM and we can hook up if you want to try that. Have two units in Chantilly also.

I hope this problem doesn't come back for my car. I have been seeing 243 volts on my charger.

As for the 277V charging that is a different set up and don't know if they were ever affected.
 
I'm on Novec also and have not had a problem since the last post above. I believe it was a software bug and was corrected by an update. Actually I was having the issue in OC Md. not here, same thing I haven't had issues there either.

Given the high heat we are suffering I wouldn't be surprised if Novec is playing with the voltage, raising it from the substation out, to reduce amperage levels. They can't play with voltage levels on a local street or individual houses, except for the A/C unit relays turning on and off to conserve power or prevent the brown out. THey are fixed taps on a transformer and would be very labor intensive. The substations I could see the possibility they could dial voltages up and down based on loads.

I'm in SR about a mile from Royal Farms if you want to come and test your car at my house. My neighbor just got a wall charger installed also. 60 Amp settings though. send me a PM and we can hook up if you want to try that. Have two units in Chantilly also.

I hope this problem doesn't come back for my car. I have been seeing 243 volts on my charger.

As for the 277V charging that is a different set up and don't know if they were ever affected.
Definitely appreciate the offer, but not sure if it's meaningful since we're so close. I was wondering if there was any local way to adjust voltage levels, and it didn't sound right, thanks for the confirmation that that is not an option.

Right now the inverter is showing 248, this morning it was 242, and the car still didn't accept it, even though that's perfectly proper. It may now be again 'rejecting' it. In the past even when the level reduced itself for whatever reason, there was some 'reset' interval, which doesn't make any sense to me, but at some point, the car will decide it's okay to eat the power, lol.

I'm very close to you, also, which makes it weird that you aren't having the same issues. Literally around the corner from Eastgate, off Planting Field.

The highest I've seen on my Solar Edge inverter is 249, and lowest is 240, but I don't have a record of actual max and mins, of course. I've put in a call to the electrician that installed my HPWCs, but all he could really do is measure the voltage at the HPWC which we 99.99% know is going to be the same as at the inverter. It's at the end of a 100 Amp circuit that is about 50 feet away from the breaker panel on all new wire made for sustained 80 Amp loads. Obviously the voltage drop for no load is as close to zero as you can get and that's where we are when it's testing the voltage 'acceptability'. (I do know something about these things, as I was trained as an EE. :D )

If we end up needing another local sample to test, I'll definitely keep you in mind, as it's great to have another equivalent site so close. I am about out of ideas after Tesla coming back with nothing, but if the electrician can verify (as I'm sure he will) that the power at the HPWC is 'correct', I'll have to see what Novec can suggest.