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Tracking KWH, and a question

Discussion in 'Model S' started by Mikerad, Feb 19, 2016.

  1. Mikerad

    Mikerad Member

    Jan 3, 2016
    United States
    #1 Mikerad, Feb 19, 2016
    Last edited by a moderator: Apr 5, 2016
    Oops - I posted this yesterday, but to the wrong forum (I believe). So, here goes again.


    Yesterday I became the proud owner of a 90D.

    [SUB] attachment.php?attachmentid=111781&d=1455826638.jpg [/SUB]

    I have a background in electrical engineering, so I and a certified electrician friend installed the NEMA 14-50 outlet in my garage. I am also a techno-geek-nerd,
    and I knew I'd want to track the power used by the car, so I bought a nice KWH meter from EKM that tracks many parameters, and best of all, can upload them to the cloud.
    Here's the outlet - the meter is at the top:


    Forgive the beat up wall, but note the twisted pair of wires coming out of the meter box toward the left.
    That is an RS-485 line that goes to an EKM "PUSH" box, which sends the data up to the cloud via my home Wifi (that's the Netgear box in the pic below).


    From there, I can monitor my power usage via any browser. The site is a bit buggy and I am still learning it, but it's basically functional.

    EKM screen.jpg

    I got the car home at around 5:30 pm, and sat and played with a few things. It wasn't trying to charge, but it was replenishing what I used.

    At about 9:30 pm, I sat at my desk and told it to charge via the Tesla app on my iPhone, so that I could watch it on the graph on my PC
    in real time. Cool.

    At 10 pm I played a little more. At 1 am it started a scheduled charge, which didn't last long - ended around 1:20 am.

    For this screen grab, I hovered the mouse over Amps Line 1 at the 1 am position, and you can see that the L1 current was 40 amps.

    There are tons of other bits of data available, but for now, these are the ones that interest me.

    I'll apply for Time of Use metering as soon as the car is registered; after that, I will pay 4 or 5 cents per KWH (depending on which exact plan I choose) for off-hours consumption.
    My daytime consumption should cap out at around 10.5 cents per KWH at peak times, because I believe I have sufficient solar capacity to not need to pay NV Energy. We'll see.


    Now my question:

    Tesla advertises a theoretical range of 288 miles for the 90D.


    My car is charged to 81% right now - I meant to charge to 80%, but I fat-fingered the slider. It's showing 237 theoretical miles.

    81 percent.jpg

    That should mean that 100% is 293 miles, a little better than advertised.

    I get that these numbers don't mean much in the real world, with all the variables out there, and that the range will be reduced somewhate as the car ages. Still, I was surprised to find a full-range number that beats what's advertised.

    Does anyone else have "brand new" numbers to share? Of course I'm most interested in the 90D, but numbers for any model would be relevant. I tried to search for this on Volkerize, but came up empty.

    - Mike.​


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