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Trunk/Boot Charging Hack?

Discussion in 'Model S: Battery & Charging' started by randvegeta, May 10, 2017.

  1. randvegeta

    randvegeta Member

    Joined:
    Dec 24, 2016
    Messages:
    106
    Location:
    Lithuania
    Hi everyone.

    The other day I was staying somewhere in a 5th floor apartment. No charging anywhere nearby so I had to throw an extension lead out the window to charge the car over night. The extension lead didn't get in anyone's way as it went over a tree that my car was parked next to.

    The extension lead is just for a normal wall socket, so max capacity is 13amps. The lead is actually on a large box that has a roller where the cord coils into.

    Any way.. the box itself is chunky enough that it won't actually fit UNDER the car (at least not at the same time the UMC is plugged in) and it doesnt seem right to leave a box out in the elements where it may possibly get wet. So I ran the cord into the boot (trunk for the Americans here) and the box was just sitting in my boot. I then connected the UMC and ran that out the rear window. Since I knew it wasn't going to rain and the neighborhood is quite safe, I didn't mind leaving my windows slightly open for the 24 or so hours I was parked.

    I noticed however the charge port is partially accessible from the inside of the boot. I was wondering about hacking this a little so that I can charge from the inside of the car without having to run the UMC through an open window.

    The 13amp extension lead is thin enough that the boot can be closed without crushing the cable, but the UMC cable is far too thick for that. This is obviously not going to be a primary means of charging, but as I will return to that location ,and probably find myself in similar situations many times in the future, it would be nice to have a more discreet way to charge in public when parked for long hours.
     
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  2. LuPapa

    LuPapa Member

    Joined:
    Oct 20, 2016
    Messages:
    52
    Location:
    Houston
    I don't see how a electric cord from a 5th floor apartment, over a tree, and connected to a car in any fashion is going to be discreet. Might be easier to find an exterior outlet on the building and get permission from the management to charge for a few bucks cash. "My car needs about $6 in electricity to fill up. Can I give you a $20 and plug in here? thanks!"
     
  3. randvegeta

    randvegeta Member

    Joined:
    Dec 24, 2016
    Messages:
    106
    Location:
    Lithuania
    You'd be surprised. It's really barely noticeable, even if you know the cable is there and look for it. The cable is less visible than most overhead cables like you see on telephone poles, and it blends in with the tree and grass as it runs down to the ground. The car parks just a couple meters away from the tree, right next to the grass, so it doesn't get in anyone's way.

    I'll take pictures next time. Perhaps I'll also publish my charging 'hack', when I wrapped bare wire around the Nema 14-50 plug terminals and 'water-proofed' it with Duct Tape so I could tap into a 3-phase 32amp outlet. worked like a charm!
     
  4. randvegeta

    randvegeta Member

    Joined:
    Dec 24, 2016
    Messages:
    106
    Location:
    Lithuania
    As promised. Behold, my genius solution!

    It is actually fairly discreet. The cable runs from my balcony, over the tree and onto the grass which is directly behind my car. The cable is not really noticeable unless you are looking for it.

    The extension lead slips into the boot/trunk WITHOUT being pressed or crushed. That particular panel gap is actually quite large and you can pull / push the cable in and out.

    The extension lead connects to the UMC which I then feed out of rear window. I close the window as much as possible, but not so much that it would crush the UMC cable. Then plug in and charge away.

    The extension lead is pretty thin and cannot charge at full power (12amps) for long. The car automatically limits the current to 9amps and it stays like for the entire charge. I get about 9-10km/h charge rate. When I started charging, I had just 40km left, so it took 24 hours to get back up to 90%. But I'm here for a week so I'm in no rush.
     

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  5. Snowstorm

    Snowstorm Member

    Joined:
    Dec 8, 2016
    Messages:
    295
    Location:
    Ontario Canada
    9-10km/h charge rate is pretty amazing for 9amp. Do u have a 220v socket?
     
  6. randvegeta

    randvegeta Member

    Joined:
    Dec 24, 2016
    Messages:
    106
    Location:
    Lithuania
    Yeah it's 220v. I'm in Lithuania so all sockets are 220-240v by default.
     

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