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More voltage drop charging with my Tesla than loaner vehicle

Discussion in 'Model S: Battery & Charging' started by punkchip, Jul 26, 2014.

  1. punkchip

    punkchip Member

    May 25, 2013
    #1 punkchip, Jul 26, 2014
    Last edited by a moderator: Jul 26, 2014
    Edit : by the "owner" at the title of the thread I meant loaner... (mod note: I fixed the typo :) - Bonnie)

    Hey there,

    Got my Model S in August 31st 2013, P16658.

    I live in an apartment buildin, and the wire is quite long to the breaker. . Theorically on my 208 V plug, i Could get 24 Amps (30 amps circuit). However I never got that high because everytime I got 24 Amps, the Voltage would get to 195-196V, which is a drop too high according to the Code. Instead I was charging ad 18 Amps and the V reading was about 200 ish. I once tried to charge at 24 amps and after a while the car lowered it to 18 amps with a warning message (Bad wiring or extension cord used).

    So two days ago, I got a loaner S85 kWh with about 6000 km on it, P36xxx When i tried to charge it at night, it was to 24 amps. Surprise! All the time it was charging I was getting 198-200 V and was able to complete the charge (few hours) at 24 Amps.

    That is using the same UMC.

    Now I have back my Model S (24 000 km) since yesterday. I tried charging it ad 24 amps, and the Volts drop to 196 ish again. I cleanned the charge port with a cotton swab, but that did not improve things. Also apparently they uploaded the latest firmware version

    So my question is, Did I have luck two days ago with the tension coming to my appartment building up to my outless, or is it possble that my battery have some sort of higher resistance ? (both had the dual chargers, if that change anything)

    Sorry for my English, and thanks for your help.
  2. Electric700

    Electric700 Active Member

    May 21, 2013
    Florida, United States
    I know there have been some improvements to the battery/charging system, as some people are getting theirs upgraded for free based on Tesla's recommendation. So, it could be that.

    Also, from a safety standpoint it's probably better to just charge at the lower 18 amps setting as that will generate less heat for the longer wire length that you have.

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