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Can't charge above 30 Amps

Discussion in 'Model S: Battery & Charging' started by newbie1235, Apr 20, 2016.

  1. newbie1235

    newbie1235 Member

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    I know, I've read all the info and issues on this and still can't seem to get this corrected. I've been just dealing with it and it pains me b/c I we were debating about getting a second Tesla, but I still can't charge above 30 amps. I understand 30 is fine, but if it promises 40, I would like to do 40. Plus, we were looking at a second Tesla so if I can't even go past 30, what is the point anymore.

    - Every time I switch to 40 amps or even push it up from 30 in increments it defaults back to 30.
    - I brought my charging cable to Tesla and charged there fine for the whole 2 hours at 40 amps.
    - I had the electrician that installed it come back and he charged me (different story - b/c technically it really isn't what I paid for) to check why it wasn't working and could not find anything wrong.

    Tesla says it's coming from the wall, so there is something wrong there. But when the electrician says there's nothing wrong, I don't know who to turn to now. Do I call my electric company to check?

    Any other ideas?
     
  2. MorrisonHiker

    MorrisonHiker Beta Tester

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    When I had my NEMA 14-50 outlets installed, I found a local owner who volunteered to come by and test out both outlets. Have you asked around to see if someone could stop by? If they can charge at 40 amps on your UMC, then it would mean something is wrong with your car. If they have the same 30 amp limitation then something could possibly be wrong with your UMC or wiring. Ask if they can bring their UMC by as well and you should be able to narrow down where the problem lies.

    Also, you might consider trying a different electrician if you find the problem is with the wiring or breakers.
     
    • Love x 1
  3. steve841

    steve841 Active Member

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    Electric co wont help.

    It's something from the panel to the unit. I'm sure your guy did fine work ... but it seems to me that's where the issue is.

    Have you tried it at a time when there is little to no draw on that panel?
     
  4. Lloyd

    Lloyd Active Member

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    I bet you have a voltage drop when you start charging. What is the voltage when you start charging, and when you are under load? What size wire did your electrician use? It should be #6 per Tesla instructions.
     
  5. Adrien

    Adrien Member

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    Voltage drop is the most likely case here or you have bad power coming in (Harmonics, power factor, etc) but I'm not sure if the car monitors those things.
     
  6. newbie1235

    newbie1235 Member

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    Yea it's the voltage that's dropping. Last time I notice it's fine when it's around 223 and drops below 200.
    The wire #6 is what he used, I think I checked back when too and made sure. You would think paying the guy to install, he would check to make sure everything works as promised. He was even the referred ones from the tesla page.
    I also turned off everything (all other breakers) except for the 50amp breaker to the car. Charged fine and then dropped again.

    Hmm I do see some people around NH that have teslas but it's really just by passing. I will ask if I ever meet one ;)
    I just figured since it charged fine at the Tesla SC with my cable and car then those two could be ruled out.

    Really stinks because I wanted to install the HPWC if we were getting 2 teslas :(

    I don't know how Tesla is going to deal with all these side issues when the Model 3 comes out.
     
  7. Lloyd

    Lloyd Active Member

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    You should not get that kind of drop. Contact your Power company and show them. It is likely then the feed to your home, or transformer if #6 was used. You may have issues with other power uses in your home.
     
    • Like x 1
  8. brkaus

    brkaus Member

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    Perhaps check the voltage on an unrelated outlet while the car is charging. You could use a multi-meter, a plug in kill-a-watt has voltage measuring, and some ups show line voltage.

    If an unrelated outlet drops significantly it isn't the circuit to the car.

    You could also check it across the breakers, but if you don't know what your doing its best to stay out of there.
     
  9. newbie1235

    newbie1235 Member

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    Yea i really don't know what I'm doing. I guess I'll just call the electric company and tell them.
    It'll take a whole month before something gets sorted out like always :|
    Thanks for all the great advice guys.
     
  10. Barry

    Barry Member

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    223 to 200 is a huge drop. 23V * 30A = 690W loss. That loss is likely heating something up, so it could present a fire hazard. Is the breaker heating up?
     
    • Informative x 1
  11. tga

    tga Active Member

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    Agreed, this is dangerous. I wouldn't charge until I figured out the problem (where the voltage drop is occurring).

    If you don't feel comfortable/don't know how to measure voltages, have the electrician come back and take measurements while the car is charging. If the voltage is down to 200 at the main breaker or other circuits, the problem is in the meter pan or feed from the utility. If not, you have a bad connection somewhere (either at the breaker or outlet). Something should be getting hot.
     
  12. linkster

    linkster Member

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    Does tga live near you (volunteering his services :D)? Checked in with my Live Free or Die utility bud and he said to call the utility company and tell them that your licensed 'electromagician' double checked the install and provide them your voltage drop data and they will hang a recorder on your meter to determine if the issues lies with them.

    Good-Luck
     
  13. tga

    tga Active Member

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    Actually, OP, if you're near me, I can stop by with a voltmeter and we can take some measurements (I just re-read the thread and saw your reference to NH in post #6). My schedule's a bit crazy for the next couple of weeks, but PM me if you want to try to coordinate.
     
  14. linkster

    linkster Member

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    Quadruple rep pts. (the "old" days, lol) for tga's most generous offer !!

    Please keep us updated.
     

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