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15% battery question

Discussion in 'Phantom 2 Vision Discussion' started by gfredrone, Jan 25, 2014.

  1. gfredrone

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    Will the P2V come home and land at the 15% level or does it just start landing at its current position? Thanks.
     
  2. Iceman

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    Like to know this as well as I always come home & land when I reach 30% will be good to know when level goes low
     
  3. gfredrone

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    Same here. Didn't want to chance it not knowing. Still coming up the curve here. Thanks in advance for any input from the pro's here.
     
  4. MikeON

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    It will start to land wherever it is when it hits 15%
     
  5. gfredrone

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    Ok thanks. One more question. At 15% will there be enough juice to safely make it home if your distance is reasonably close to the home point? I guess I'm asking is there enough power remaining at 15% to maintain altitude as you make your way home?
     
  6. MikeON

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    Basically, I've found you have a few minutes, and you have to keep giving it up-throttle to keep it in the air. It will try to land if you center the stick. Best to be on the way back to home point or other safe landing spot when you hit first lever warning (mine is set at 25% at this time).
     
  7. themosttoys

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    I just posted in another thread (viewtopic.php?f=7&t=7021&p=55318#p55318) my experience with low battery. Basically (in my experience, especially in wind) the P2V will come down at 15%). Yes you can delay the descent (basically hover) by full throttle up, but you can not fly as normal (ex: you can not overcome a strong wind and fly home) and within a few minutes the P2V will be on the ground (one way or another). Temperature, wind, battery condition, ... all play a factor, but when you are at 15% battery your flight is basically over (plan ahead.)
     
  8. gfredrone

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    Thanks for the responses. I'm going to set my 1st level warning to 25% like MikeOn to give myself a little more time without the bells and whistles going off.

    I just ordered 2 more batteries on eBay... :D $299 + $13 expedited ship from US seller.
     
  9. iDrone

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    15% of 25 minutes is roughly 3.75 minutes on a good battery... Auto-landing initiates immediately and begins a slow decent wherever it currently is. So when you hear your first warning at 20% or 30% consider flying back closer to HOME.

    Assuming you have 3.75 minutes at 50% max throttle & velocity (50% of 35moh = 17.5mph) and .75 of those minutes would be used for your descent, 3 minutes at 17.5mph covers 4260 feet (1408 meters) distance back to HOME under "ideal" (calm) conditions. You will burn considerably more reserves fighting wind & turbulence.

    So, in most cases (unless your me, Uncle Fester, BendronePilot, themosttoys, and a few other long-distance fliers) you'll probably have enough juice to get home & land safely, particularly if you heed the first warning and fly closer to home and maintain LOS (line-of-sight).

    If it initiates an auto-landing, throttle up a bit to gain enough altitude to clear people & obstacles and bring Vision in towards you... Use the Radar display if you're having trouble with orientation & distance or difficulty seeing the aircraft. Try not to "floor the sticks" else you risk dumping the remaining charge in the battery.

    Hope that helps!

    iDrone
     
  10. Pull_Up

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    Just to add into the mix that generally, to prolong the life of (our **** expensive) lipo batteries, discharging much below 20% should be an infrequent occurrence...
     
  11. MikeON

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    Interesting comment, since the manual says to discharge below 8% every 20 charge/discharge cycles. My problems with premature autolanding started the first flight after I had drained and recharged the battery per the manual, although I'm not sure that was the reason.

    viewtopic.php?f=7&t=6488&hilit=autolanding#p49458
     
  12. iResq

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    You're right however I have not seen any other mention of this in any of the articles I have read on lipo batteries.
     
  13. Pull_Up

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    Me neither. However, it's in the manual as a definite procedure to follow. I suspect it's to keep the smart circuitry calibrated for a accurate % readout on the app.

    Another reason to make the regular in-flight discharges not much lower than 20% if you throw a deep discharge in the mix every 20 flights...