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TB48 Showing 5444mAH total capacity w/ 1 charge cycle

Discussion in 'Inspire 1 Discussion' started by jb., Oct 27, 2015.

  1. jb.

    jb.

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    Bought a new TB48. Hadn't used it yet when the 1.4.10 firmware came out, so I went ahead and installed the firmware on the new battery then did a deep discharge from the 60% or so it was sitting at down to the Inspire landing and then let it run idle for another 20-30 minutes until the Inspire shut off. During the discharge, it said the total capacity was 5444mAH but I figured it'd get itself figured out after the calibration.

    Charged it back up to full and it still reports 5444mAH total capacity.

    Is it defective?

    I have another TB48 that reports 5700mAH (1 charge cycle, new at the same time) and two TB47s that report 4500 (2 charge cycles) and 4470 (2 charge cycles). All of those seem reasonable.
     
  2. The Editor

    The Editor Moderator
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    Your mistake was probably doing a battery calibration from 60% rather than 100%. The firmware has probably told itself now you have 95% battery life remaining rather than the 100% you would expect from a new pack.
    Always calibrate from 100% charge level since the fuel gauge needs to be taught what totally full is and what totally empty is.
     
  3. SultanGris

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    It's my understanding you're supposed to do the full discharge till it shuts itself off from a full charge. Don't know for sure what happens if you don't but I'm guessing it won't reset correctly. Also never fly on a partial battery that has self discharged, it's a good way to crash your inspire and cause major damage. Batteries are likely to go from 60%-5% or any other random numbers % sudden drop instantly which can be very bad. Inspires can't handle crashes very well.
     
  4. jb.

    jb.

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    During the discharge, it was flying a grand total of 1' off of the ground... so I wasn't overly worried about it falling out of the sky.

    If it needs to happen from 100%, I'll do it again now that it is charged. This whole deep discharge thing is a royal pain in the ass. There really should be a better way to do this than "put it in the Inspire and fly it until it dies."
     
  5. SultanGris

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    That's a good height for this process.

    You can always buy a $500 battery charger to automate the process but personally I'd rather fly for 12 min.
     
  6. jb.

    jb.

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    Yeah. I'm wondering if I can just put a couple of 12V bulbs in series and discharge it that way.

    I hear the $500 charger doesn't even work for this process anyway.
     
  7. SultanGris

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    Possible I suppose, can't say for sure but it shouldn't really matter how it's discharged. I had my doubts about that charger working for it also but no definitive proof either way, I have no intentions if spending $500 on a battery charger, lol