Haven't seen one like that in quite some time. Here, they have the bypass/ejection lever. Place hand loosely beneath meter, pull lever, meter falls in your hand. The lever also performs the bypass function - hence my reference to it.
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Charging cuts down to 75%, Tesla says... it's my house.
- Thread starter SabrToothSqrl
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Haven't seen one like that in quite some time. Here, they have the bypass/ejection lever. Place hand loosely beneath meter, pull lever, meter falls in your hand. The lever also performs the bypass function - hence my reference to it.
I understand. Lever bypass is nicer. I just get concerned anytime the meter is pulled because there are a lot of people who don't know what they are doing and it is relatively easy to damage.
Hi guys,
I found this thread yesterday and instantly new it was a problem we have been experiencing as well. I would say that it has only happened about 6-8 times but all of them have been in the last 2 months. Exact same description. Tesla will reduce down to 30 A almost right after beginning to charge. After seeing this thread yesterday and people asking for data logs I thought I would catch it again and what do you know, it happened last night and I was able to get the data log from out TED energy monitor. Here is the screen capture for the last 24 Hours.
So the first big spike there in the evening (6 pm) we were just charging a little before going out for the night and no problems. Stayed at 40 A the whole time. Then plugged in at 10:50, made sure it was set to 40 Amps, came inside the house and looked at the app on my iPad and it was saying 30 A. Went back out and changed it back to 40 A and it appeared to stay there. I went to bed and can't tell if it jumped back down to 30 A or not. It is hard to see through the other "noise" on the graph from electric BB heaters turning on/off and other appliances but it appears that you can see the drop from 40 A to 30 A as soon as charging started.
We have chalked it up to the fact that we leave our UMC outside all the time plugged into the NEMA 14-50 outlet in a somewhat protected area but still chance of snow/water getting into the end of the plug. Maybe if there is moisture in the end of the plug when inserted into the Model S, it detects it and reduces the power. I know sometimes if we don't plug it in all the way it will say "charging problem" but in this situation it just lowers the power without notifying us about anything. Hopefully when the dryer/warmer weather comes in a few months this problem will go away. If not maybe we'll look at it closer.
I found this thread yesterday and instantly new it was a problem we have been experiencing as well. I would say that it has only happened about 6-8 times but all of them have been in the last 2 months. Exact same description. Tesla will reduce down to 30 A almost right after beginning to charge. After seeing this thread yesterday and people asking for data logs I thought I would catch it again and what do you know, it happened last night and I was able to get the data log from out TED energy monitor. Here is the screen capture for the last 24 Hours.
So the first big spike there in the evening (6 pm) we were just charging a little before going out for the night and no problems. Stayed at 40 A the whole time. Then plugged in at 10:50, made sure it was set to 40 Amps, came inside the house and looked at the app on my iPad and it was saying 30 A. Went back out and changed it back to 40 A and it appeared to stay there. I went to bed and can't tell if it jumped back down to 30 A or not. It is hard to see through the other "noise" on the graph from electric BB heaters turning on/off and other appliances but it appears that you can see the drop from 40 A to 30 A as soon as charging started.
We have chalked it up to the fact that we leave our UMC outside all the time plugged into the NEMA 14-50 outlet in a somewhat protected area but still chance of snow/water getting into the end of the plug. Maybe if there is moisture in the end of the plug when inserted into the Model S, it detects it and reduces the power. I know sometimes if we don't plug it in all the way it will say "charging problem" but in this situation it just lowers the power without notifying us about anything. Hopefully when the dryer/warmer weather comes in a few months this problem will go away. If not maybe we'll look at it closer.
NetZero, thanks for the info, but I need a lot more resolution to examine this further. 2 minutes before and after, voltage across both lines to neutral, current on both lines, and power factor. Unfortunately, TED only measures a single line (why you only see ~120V). And at least second by second (preferably much higher sampling) measurements in a csv or excel format. I wish I had a Model S here I could capture the event and attempt to reverse engineer the criteria Tesla is using to reduce current. That way, users would know exactly why they're being reduced and not be sent on a "check everything and still find nothing" chase. Quantitative and not qualitative measurements for the criteria.
Maybe the neighbors have something that fires up at night that is drawing a lot of power, affecting your voltage..... Maybe stay up one night until the charging ramps down and observe voltage displayed on the Tesla screen.
That TED application looks cool...
That TED application looks cool...
Data
View attachment Tesla Data.xlsx
I don't have one of those TED devices, so for now I'm working with VT. I called PP&L, they sent someone same day, they left footprints in the snow, but that's about all I could see.
Attached are four points at which the car reduced power to 30 amps.
Interestingly, the charge rate stays at 28-29 MPH even at the 30 vs. 40 amps...
I deleted all the times it worked at the correct 40 amps, or reduced power because it was powering up or approaching a complete charge.
Seems to occur between 6:45 PM and 9:30 PM, when it occurs. I'll take this data to PP&L in a few weeks.
View attachment Tesla Data.xlsx
I don't have one of those TED devices, so for now I'm working with VT. I called PP&L, they sent someone same day, they left footprints in the snow, but that's about all I could see.
Attached are four points at which the car reduced power to 30 amps.
Interestingly, the charge rate stays at 28-29 MPH even at the 30 vs. 40 amps...
I deleted all the times it worked at the correct 40 amps, or reduced power because it was powering up or approaching a complete charge.
Seems to occur between 6:45 PM and 9:30 PM, when it occurs. I'll take this data to PP&L in a few weeks.
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That's because the charge rate in rated miles per hour of charge is a session average, so perhaps your downshifting is occurring later in your typical cycle.
That's great data and will help them narrow it down.
Called PP&L again, they are sending someone to the house (again)... since they won't give me a time, I'm obviously not home to have the car plugged in.
Am I the only one who's being cut down to 30 amps?
Has anyone here successfully gotten their power company to fix anything?
Am I the only one who's being cut down to 30 amps?
Has anyone here successfully gotten their power company to fix anything?
No, there are handful of people here who have intermittent 30A reductions; see the thread that I referenced in post #3 to this thread:
Very frustrated with software limited charging
As for getting the power company to work with you, it's largely depends upon the size of the power company and who's working for them.
Some power companies send someone out, they stick a voltmeter on your meter and watch it for a few seconds, and when it doesn't change they say "all's good" and leave. It's like the shooter at the gun range who aims downfield, takes 10 shots, and completely misses the target with all; so he puts his finger on the end of the gun, pulls the trigger, and blows his finger off - then yells "problem's on your end" to the targetmaster. I find that power company engineers are more willing to listen than the repair techs, who get measured on how many tickets they close.
Some power companies, on the other hand, are more willing to work with you. My co-op is very helpful and will spend some time with you to understand it.
The problem you'll have is that some of the data may be lost in translation when you talk to the service operator. They may not know that you're having intermittent issues. Ask the operator to note an intermittent voltage problem, and to have the tech make contact at your site. Request that a line analyzer/monitor be put in place for a week. That might help them help you.
You said it happens maybe 10% of the time... that may not be enough to do some of the troubleshooting yourself. If it happens often enough, you can frequently do some troubleshooting that will help you identify any misbehaving appliances in your home. But it could also be the transformer, or a house that shares the transformer.
Thank you for the feedback, they said to call them tomorrow, and I will to get their 'results', however the phrase 'put a line analyzer on for a month' may be what I need to use with them. I don't know how concerned I should be. It seems to be happening a lot more now, but maybe I'm just more aware of it. I've been logging each drop, but Visible Tesla doesn't have the millisecond accuracy I'd need to spot the issue before it drops the amps.
I'm wondering if I should just set it to 35 amps and see if it just sticks at that without issue... at least that's 5 more than the 30.
I don't know what else to do, it's a fairly new (2008) house, but it's also in a rural location... most houses around me are 2-6 acre (or bigger) lots. My only large draw appliances are also from 2008 or newer. (dryer and well pump). (it's currently 50 here, so the A/C is off). nothing else should even draw much power. My entire electric bill Pre-Tesla was $75/month... (it was $175 last month).
They keep asking if I've had an electrician... my dad was one, I wired the NEMA myself with 6 gauge copper, 1' from the panel.
I'm thinking the cars just too sensitive now... it's safer I know, but it's still stressing me out... along with what I think is a newly developed rattle from my car, where my sister slammed the back door Sunday night... so yea... can't win.
it looks like some guys have had success reducing the power to 35 amps, so I'll give that a go... my normal daily commute is all of 30 miles, if that, so even a 120 could charge the thing. Speaking of, I should try that just to see what it does... I've never charged from 120 before.
I'm wondering if I should just set it to 35 amps and see if it just sticks at that without issue... at least that's 5 more than the 30.
I don't know what else to do, it's a fairly new (2008) house, but it's also in a rural location... most houses around me are 2-6 acre (or bigger) lots. My only large draw appliances are also from 2008 or newer. (dryer and well pump). (it's currently 50 here, so the A/C is off). nothing else should even draw much power. My entire electric bill Pre-Tesla was $75/month... (it was $175 last month).
They keep asking if I've had an electrician... my dad was one, I wired the NEMA myself with 6 gauge copper, 1' from the panel.
I'm thinking the cars just too sensitive now... it's safer I know, but it's still stressing me out... along with what I think is a newly developed rattle from my car, where my sister slammed the back door Sunday night... so yea... can't win.
it looks like some guys have had success reducing the power to 35 amps, so I'll give that a go... my normal daily commute is all of 30 miles, if that, so even a 120 could charge the thing. Speaking of, I should try that just to see what it does... I've never charged from 120 before.
The fact that you're only seeing it intermittently doesn't really point to a wiring infrastructure issue, rather it seems like more of a load or misbehaving appliance issue.
As I noted in the other thread, it can happen with one misbehaving appliance on a completely isolated transformer, like the example I gave from my shop. It could also be caused by bad power from the power company (although that's rare because they'd have to see crazy wild fluctuations that would show up with that magnitude after the transformer step-down).
You can try to make the argument that the car is too sensitive, but - like the other thread - the signature it's seeing is the same signature that can result in a fire. It isn't a widespread problem, or we'd have hundreds to thousands of people making complaints in that thread - I would agree generally that the car was too sensitive only if we saw a rather large group of people experiencing this problem especially on known good infrastructure. Right now, it looks like a few isolated cases due to local infrastructure. Reports are that the car will step back up to 40A to periodically "re-test", are you seeing that?
Best thing to do is to ask that the tech make contact with you rather than passing you through trouble ticketing systems. That, or ask to speak to engineering.
As I noted in the other thread, it can happen with one misbehaving appliance on a completely isolated transformer, like the example I gave from my shop. It could also be caused by bad power from the power company (although that's rare because they'd have to see crazy wild fluctuations that would show up with that magnitude after the transformer step-down).
You can try to make the argument that the car is too sensitive, but - like the other thread - the signature it's seeing is the same signature that can result in a fire. It isn't a widespread problem, or we'd have hundreds to thousands of people making complaints in that thread - I would agree generally that the car was too sensitive only if we saw a rather large group of people experiencing this problem especially on known good infrastructure. Right now, it looks like a few isolated cases due to local infrastructure. Reports are that the car will step back up to 40A to periodically "re-test", are you seeing that?
Best thing to do is to ask that the tech make contact with you rather than passing you through trouble ticketing systems. That, or ask to speak to engineering.
Progress: PP&L is installing a "voltage recorder" in the "next day or so". So I'll set the car back to 40 amps and charge up and see what happens.
of course I'll have to drive more now because my normal daily commute uses all of 2 hours max to charge up... and I'd like to see some more time spent charging logged in the meter.
I assume only large loads could pull enough to 'misbehave'... so that's 240 loads? My fridge is on a 120 line, so according to the door it pulls 15 amps max.
The well pump is 240, as is the dryer. I can not run the dryer for a few nights until the car is charged (usually done by 9pm at latest). and see what that does.
Is there a way to measure / find a bad appliance? If they pulled more than they should... shouldn't it be tripping my breakers?
My personal guess is that in a rural setting with above ground wires, my neighbors and I simply share too much equipment. so when everyone gets home at 5-7pm, turns on the lights, TV, heat, shower, oven, dishwasher, etc, I get a momentary reduction in voltage at MY house... but just a guess. (man, are we slaves to electricity, or what?!)
I did charge last night, at a set 35 amps for the whole charge without issue...
I don't know if I'll order my X85 with dual chargers, so I don't want to drop $750+ install on a HPWC... because 75% of 80 amps is still more than 30/40.
I do have a 'smart meter' that I can login to the PP&L website and pull XML data from. Why doesn't it have a line voltage recorder? If this meter is so smart...
Initially I was against smart meters just because of the whole big brother thing, but PP&L knowing when my house doesn't have power... that's kinda of cool...
of course I'll have to drive more now because my normal daily commute uses all of 2 hours max to charge up... and I'd like to see some more time spent charging logged in the meter.
I assume only large loads could pull enough to 'misbehave'... so that's 240 loads? My fridge is on a 120 line, so according to the door it pulls 15 amps max.
The well pump is 240, as is the dryer. I can not run the dryer for a few nights until the car is charged (usually done by 9pm at latest). and see what that does.
Is there a way to measure / find a bad appliance? If they pulled more than they should... shouldn't it be tripping my breakers?
My personal guess is that in a rural setting with above ground wires, my neighbors and I simply share too much equipment. so when everyone gets home at 5-7pm, turns on the lights, TV, heat, shower, oven, dishwasher, etc, I get a momentary reduction in voltage at MY house... but just a guess. (man, are we slaves to electricity, or what?!)
I did charge last night, at a set 35 amps for the whole charge without issue...
I don't know if I'll order my X85 with dual chargers, so I don't want to drop $750+ install on a HPWC... because 75% of 80 amps is still more than 30/40.
I do have a 'smart meter' that I can login to the PP&L website and pull XML data from. Why doesn't it have a line voltage recorder? If this meter is so smart...
Initially I was against smart meters just because of the whole big brother thing, but PP&L knowing when my house doesn't have power... that's kinda of cool...
Good thing they'll put the voltage recorder on there. It would be good, as you note, to try and trigger the condition while it's on your line.
Even the most basic of appliances can misbehave. For example, in my shop I had a bad 4-bulb ballast in a fluorescent fixture; turning it on/off caused a significant voltage anomaly, enough to trigger the Model S. My suspicion is that reactive current triggered it. Also, motors that rely upon starter capacitors can cause the problem; if they have a bad starter capacitor, the motor can either fail to start (you'd know this), or could draw hundreds of amps for a fraction of a second. It won't trip your circuit breakers because they require a bit more time to trip (unless there's a short circuit with a sufficient fault path).
If you share a transformer with neighbors, then very possibly this could be the case. When the power company is there, ask them how big the transformer is that serves your home.
When the power company is there, tell them that you currently have a continuous load of 40A and are considering another continuous load of 80A to charge the car. I can pretty much guarantee that you're undersized transformer-wise for that; they might advise you what you need to do to upgrade your service.
It may not monitor sub-second intervals. Then again, it might.
I had the same thing happen several times. My HPWC is dip-switch limited to 60A, but interestingly enough I noticed through the Tesla App on my iPhone that the car would claim to be charging at 64A. This would trigger the situation you see, and bump me back to 48A frequently.
So I set a 60A limit in the car, and the problem hasn't happened again.
May be just coincidence, but it sure seems to behave a lot better now.
So I set a 60A limit in the car, and the problem hasn't happened again.
May be just coincidence, but it sure seems to behave a lot better now.
Thank you Flasher, you guys are really thorough on this forum!
Agreed Chuck, all of this effort may just result in me setting the car to 35 amps permanently, and it being able to charge just fine at 35... but my OCD/want to know everything mind kicks in and I want a definitive... THIS is why you can't sustain 40 amps... so "the wiring is bad outside your house a mile away" or "too many houses on this line" or "aliens" or... whatever... you know... it's the not knowing that kills me. And charging at 35 vs 40 amps won't ruin the car for me, it's just one of those things that eats at you.
I could start shutting down breakers to see what happens, but it happens so sporadically, I'm not sure I could find it...
Chuck, if you're stuck at 60 Amps, what's the reasoning it's set to that? Why aren't you able to do the spec of 80 amps?
If I have a HPWC, and it backed down from 80 amps, does it also do 75% which would be charging at 60 amps for me?
Agreed Chuck, all of this effort may just result in me setting the car to 35 amps permanently, and it being able to charge just fine at 35... but my OCD/want to know everything mind kicks in and I want a definitive... THIS is why you can't sustain 40 amps... so "the wiring is bad outside your house a mile away" or "too many houses on this line" or "aliens" or... whatever... you know... it's the not knowing that kills me. And charging at 35 vs 40 amps won't ruin the car for me, it's just one of those things that eats at you.
I could start shutting down breakers to see what happens, but it happens so sporadically, I'm not sure I could find it...
Chuck, if you're stuck at 60 Amps, what's the reasoning it's set to that? Why aren't you able to do the spec of 80 amps?
If I have a HPWC, and it backed down from 80 amps, does it also do 75% which would be charging at 60 amps for me?
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That's not correct, it's one of those weird things that even some electricians get wrong. The basic rule is that the breaker / OCPD and conductors must be sized to handle all intermittent loads plus 125% of the continuous load offered. The misinterpretation comes in "continuous load", which is very specific yet misused.
HPWC's already include the 125% factor in their breaker size calculations. An HPWC configured for 80A breaker size offers 64A charging.
If you plug in your HPWC and the car says it's charging at 64A, that means it's configured for an 80A breaker, not a 60A breaker. A 60A breaker setting will charge at 48A. You should try turning off the HPWC breaker and turning it back on, then try again to see if it tries charging again at 64A.
The setting to be used depends upon the wire installed. Do you know the size of the wiring the electrician installed?
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the HPWC says it needs 3 gauge. Just getting 6 into my Nema 14-50 was fun... at a 2' run I could have used 8 gauge (and did) until it kept cutting down to 30 amps, so I swapped in 6 gauge... no change.
"For most branch circuits of 100A, use 3 AWG (26.7 mm2), 167°F (75°C)
copper wire. Ground wiring can be a maximum of 4 AWG"
https://www.teslamotors.com/sites/default/files/blog_attachments/ms_hpwc_installation_guide.pdf
"For most branch circuits of 100A, use 3 AWG (26.7 mm2), 167°F (75°C)
copper wire. Ground wiring can be a maximum of 4 AWG"
https://www.teslamotors.com/sites/default/files/blog_attachments/ms_hpwc_installation_guide.pdf
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