Cinestar X8 parallel battery power option w MK boards

Discussion in 'Cinestar 8' started by Derek Cooper, Sep 22, 2014.

  1. Derek Cooper

    Derek Cooper Active Member

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    Question - as a parallel battery option, would you wire one battery to the MK Double Quadro V3 Cool using the EC5 connector supplied, and solder a second connector to the second board for the other battery in lieu of one connection to the board using a parallel cable between the LiPos?
     
  2. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    That runs the risk that if the two LiPo's are at different voltages (and they almost certainly will be), then you may have a voltage difference between the two MK Cool boards. Very, very, bad idea. However, it will not last for long and you will have discovered how the MK Cool board can be used as a fuse. :)

    I would recommend making up a short Y-cable that allows you to connect both batteries together and present a single connector to the MK Cool boards.

    Andy.
     
    Dan Walker and Steve Maller like this.
  3. Derek Cooper

    Derek Cooper Active Member

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    You are a never ending source of knowledge Andy! Thanks.

    The idea came up in the batteries thread.
     
  4. Steve Maller

    Steve Maller UAV Grief Counselor

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    I've been running paralleled 6S LiPos ever since i built my big X8 and I always have used a 'Y' to the two batteries. It's the only way.

    Someday somebody will build a truly fault-tolerant power system. It's absolutely possible, but for now there doesn't seem to be much incentive. Probably it's a cost thing. But this has been discussed ad nauseum elsewhere, so I'll just shut up. :rolleyes:
     
  5. Derek Cooper

    Derek Cooper Active Member

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    The idea of it is really interesting, indeed. For now, I'll go with the "Y" to the two batteries.

    Been using eCalc to roughly model the copter, even though current model doesn't support coax. Spoke to Markus, he needs 7 more reliable models for testing till he can incorporate coax. Says that'll be a while.

    You've settled on the 16,000s in parallel Steve?
     
  6. Tristan Twisselman

    Tristan Twisselman Active Member

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    My Power Distro has two separate leads coming out, 2 positive and 2 negative so i have two ec5 connectors. I plug one battery into each and have never had an issue.
     
  7. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    Good point, Tristan. I suspect if you tested the continuity between those two positive leads you'd find they were connected together -- and the distro board is merely acting as a Y-cable.

    Andy.
     

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