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Propulsion output is limited when battery drops below 3.50v

Discussion in 'Inspire 1 Discussion' started by GizaDog, Apr 4, 2016.

  1. GizaDog

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    Just wanted to see if anyone else is seeing this same thing? It seems to be happening with some of my batteries that have more flights on them. When is it not safe to fly with lower voltage?

    Inspire 1 Pro

    [​IMG]
     
  2. msinger

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    The propulsion throttle is something new DJI added in the 1.6 firmware. In order to prevent the battery from reaching a dangerously low voltage, the propulsion will be limited and/or your Inspire will auto land when the battery reaches the critical level. Both are fail safes that aim to prevent the battery from reaching 3.0V (where it would turn off mid-flight).

    It's generally a good idea to land before the first battery cell reaches 3.3V. As you can see in your screenshot, you're battery is right at about the level where you should be considering landing.
     
  3. GizaDog

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    Thanks. I'm getting these warnings when the battery is full as well. My feeling is that the extra weight of the X5 is taxing the batteries faster then the lighter X3.
     
  4. gruvpix

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    Word. I don't mind this failsafe as generally I don't need to ascend vertically that fast, and it doesn't seem to limit horizontal speed as much. It was originally advertised as a way to failsafe cold batteries, but I get the warning on warm batteries as well.
     
  5. ianwood

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    3.47V is too low. You should be on the ground.
     
  6. GizaDog

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    That would mean the battery is not useful on the X5 any longer and needs to be used only on the X3.
     
  7. ianwood

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    Maybe. Could be a bad cell.
     
  8. GizaDog

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    All cells are reporting good and matched levels.
     
  9. The Editor

    The Editor Moderator
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    Depleting the packs that low (below 3.5v per cell) is asking for trouble and your Lipo will fall of a cliff shortly thereafter.
    The discharge curve of a lipo is very flat but when it goes below 3.5v per cell you are living on borrowed time in the air.
    This is why DJI built in these protections to stop people murdering their packs and trying to squeeze rediculous last seconds out of them.
    At 3.5v per cell, assuming a 0.2v rebound when the load is removed will recover the pack back to 22.2v or around 3.7v per cell which is fine.
    Anything below this (and asking the pack for large current demands) will only end badly.
     
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  10. GizaDog

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    Yeah. I think ill not use this one on the X5 anymore. Get scary every when the battery is fully charged.
     
  11. slim.slamma

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    You need the battery modification:D
    At 30% I land with average flight time of 24 minutes on a fully charged 4800mah tb48. At 45% I start to see that dreadful Red voltage warning:eek:. Solution easy on the gas from start i get 28 minutes flight time to the yellow voltage warning at 20%
    X3 myself without the mod at 95% i get red voltage warning seems like the entire flight..
    You most likely trashed your battery like myself.
    Mod up or buy new batteries & never fly below 30%. X3 or x5 with a trashed battery is all the same.
     
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  12. woodc

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    Hmmm...this is disturbing. As soon as we upgraded from the X3 to the X5 we started getting this frequently (possibly this just coincided with the firmware update) I assumed it was as stated...just the flight controller neutering things slightly to reduce load thus nothing to stress about. FWIW I am fairly certain this has happened with some brand new batteries as well :-/ We see under 15 minutes of flight time with the X5 and that is running down to around 20%
     
  13. woodc

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    I went back and checked my logs. 13 minutes with the X3 (around 20%) and now 10 minutes with the X5 is what we are averaging.
     
  14. Hercules_One

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    I
    didn't know that, thanks editor!
     
  15. Kilrah

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    My rule is on the ground at 20%.
     
  16. slim.slamma

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    30 % is what I would recommend after owning an i1 over a year but 20% coming from you is good as gold.
    So do you get the propulsion and cell voltage warning often with your battery's? I feel like bringing my packs down to 20% degraded my batt's. Otherwise I don't see how battery degradation occurs so quickly.
     
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  17. Kilrah

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    Never had it. But then again I only have an X3.
     
  18. slim.slamma

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    I only have a x3
    You remove them at 20 or land at 20.
     
  19. Hercules_One

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    Between 20 and 30 is my rule, closet to the 30%
     
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  20. slim.slamma

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    What I don't like about propulsion warning is it started with an update. Last winter I never got this warning. What did it fix? By adding it seems it created more pilot issues then it resolved.
     
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