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Critical low power warning

Discussion in 'Pro/Adv Discussion' started by Denver_Flight, Jan 25, 2016.

  1. Denver_Flight

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    Hi All, I was flying today and had a warning I've not seen before. I was only a minute into flight with a fully charged battery in my P3P, when all of a sudden I got a warning "critically low power". I'm in Phoenix, so it wasn't cold out (60 degrees or so). I was giving it pretty hard throttle, but the voltage was showing over 4 volts the entire time. I was only a few hundred feet away so was able to bring it back and safely land. Wonder what caused this, just my heavy right finger?
     

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  2. RasterEyes

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    Post the link to the healthydrones report and a link to your .dat file.


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  3. Denver_Flight

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    What is .dat file?
     
  4. RasterEyes

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    It's on the sd card from your craft.. Mount the SD card to your Mac or pc and you should find it. Some of the talented folks here can get some advanced data from it.


    Sent from my iPad using PhantomPilots mobile app
     
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  5. Denver_Flight

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    The only files I'm seeing are jpg, mov, srt, and dng. Won't allow me to upload anything other than jpg. Where do I find .dat?
     

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  6. BVC

    BVC

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    I had the same issue with mine.

    No one on here could answer it.
     
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  7. Denver_Flight

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    Has it happened again since, with same or different battery?
     
  8. msinger

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    In your flight log, the voltage hit 3.33 volts. That critical low battery warning kicked in to prevent your battery from reaching 3.0 volts and shutting off. It sounds like all was working as designed. Try ascending a little less fiercely.
     
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  9. happydays

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    @msinger where are you seeing this from the information above? Trying to learn here ow to interpret the data. I get the .csv file from the HD site, but I can't see the individual cell voltages. Maybe I'm not doing this right? Any help would be much appreciated.

    Still unable to retrieve my own .dat files as I'm using a Mac and it won't mount the device.
     
  10. msinger

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    You can see it in this file:
     

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  11. happydays

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    Thanks - that's exactly the .csv I was able to download from HD. Just can't see where you're getting the <3.3v / cell from? Am I missing something?
     
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  12. msinger

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    See the "voltage" column. Divide that number by 4 to get the voltage of a single battery cell. That's of course the average and will only be accurate if the cells are balanced.
     
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  13. happydays

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    Right - I get it now. I was doing exactly the same thing, but applying a conditional formula to the spreadsheet to highlight any values below 3.3v - but there weren't any. The lowest voltage is 3.33425 volts. At least I'm not losing it completely!
     
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  14. msinger

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    Well, now you'll know how to edit your formula for next time ;)
     
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  15. Denver_Flight

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    I see now, thanks for the help. I always watch the voltage, it never dropped below 4.0 on the display. What would cause the variance?

    I was giving it full throttle up and back for a nice flyaway shot, which I've done many times before. Perhaps battery is just getting old and has lost some of its juice. Next time I'll go a little slower...
     
  16. msinger

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    Are you running firmware 1.5? If so, you should upgrade. There are many reports of voltage discrepancies from pilots running that firmware.
     
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  17. RasterEyes

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    Denver, cold will also affect the rate of voltage drain. You may just need to "chill" with the acceleration in colder temps.


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  18. Denver_Flight

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    Good advice. I'm in Phoenix at the moment, temp was around 60°, but probably still need to be less aggressive on the throttle.
     
  19. John Locke

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    100%, if you're flying with 1.5 firmware you have a flaw in the firmware that reads the individual voltages from each cell WRONG, lower than reality. The display you see will have an accurate reading, however the firmware isn't seeing the same voltage, a coding error apparently. Hence premature auto-landings are initiated, and sometimes power shut down mid-flight! Do not fly with 1.5!
     
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