TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker or making a Paypal contribution here:

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 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.

Share This Page