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BMB (Battery Managment Board) in ESS power draw.

Discussion in 'Roadster: Technical' started by spaceballs, Aug 30, 2014.

  1. spaceballs

    spaceballs Member

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    In case anyone was curious BMB board draws around 0.21 watts each, and with 11 in the ESS, that 2.31 watts that is always in use.
    Say for 50kwh pack that about ~2.5 years with the service disconnect pulled out before the pack is drained.
     
  2. hcsharp

    hcsharp Active Member

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    Thanks for the info. I'm surprised it's that much.

    I'll have to remember not to leave my car unplugged that long with the service disconnect pulled.:biggrin:
     
  3. spaceballs

    spaceballs Member

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    Instead of creating a new thread, thought I would put this here.

    Normally the BMS/BMB will bleed bricks as needed after a charge, which can be interrupted by turning on the car and put it into drive then power off. After that point it will not try to continue bleeding those bricks. But I noticed something interesting that if any bricks has a really high voltage of >4.1v that it will start bleeding those bricks even after you drive the car and put it into park. I'm guessing this covers an edge cases where somehow the batteries end up with an higher voltage after a drive. Note i was in standard mode for this.
     

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