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Advanced Low voltage during flight

Discussion in 'Phantom 3 Help' started by P3A-Brasil, Jul 18, 2015.

  1. P3A-Brasil

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    Hi!
    I was doing a short flight yesterday and had a problem. When I switched on the motors the battery was at 45%. I took off and just raised a bit over the home point. When the battery was about 37% a "critical low voltage" warning appeared on the top of the screen and the P3 started to slow down the motors and descended. Fortunately I was over the home point and could land safely. But if I was far I could have lost it.

    But now I'm afraid of going far with it. Does that means my battery is bad?

    What's the normal voltage during flight? I did another flight about an hour ago and printed the screen showing the voltage when the battery power was around 37%. Is it the normal readings for the voltage?

    Tks

    IMG_3383.PNG
     
  2. bbfpv

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    If you're saying that a you started the quad up w/ a fully charged battery and it read 45%, then either your battery wasn't fully charged, or it's a bad battery. Try it again, fully charged. Also be certain that the battery is firmly and completely inserted into the battery bay. Loose leads will report low voltage.
     
  3. P3A-Brasil

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    The battery was not fully charged because I had made a flight the day before. But even when it reached 37%, it should be able to keep the quad up.

    I just wanted to know if it is normal to get this voltage of 3,48V as seen on the print when the battery is around 37% power.

    When I start a flight with the battery fully charged, the voltage level on the cells stays between 3,69 and 3,90V depending on the movements I make (raising, foward.. etc). Is it all normal? Are these the readings you get too?
     
  4. bbfpv

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    I don't recall the voltage readings, but I've definitely been to 30% w/o a critical voltage reading. Check that the battery is seated securely.
     
  5. Kyniek

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    I had similar situation - battery charger approximately 60% - whet I took of and was increasing height - at 120m I had that warning - immediately I pressed RTH.

    I spoke to few people familiar with RC models, and they said that load during increasing height could be to high for battery which wasn't fully charged... The less charged battery, the less power it can deliver. So - when battery is running I should avoid aggressive flying.
     
  6. bobmyers

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    When you take of with a battery that is less than fully charged and under 50% , the batteries are pulling a lot of current and will create a low battery warning and may even land the Phantom depending on the power used. For safety sake, always start the day with a fully charged battery.
     
  7. TAZ

    TAZ

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    I question this insight, as it's not been my experience. Many times doing close proximity flights all under 50% and never a warning and certainly never a landing. Am I missing a consideration of a condition you're flying under? If someone was to strictly read your recommendations, it might suggest someone under 50% "WIlL create a low battery warning and may land"? I've not experienced that, but my flights might not strictly meet your experience. Can you clarify?
     
  8. bobmyers

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    If your battery is under 50% and you are flying hard, such as ascending rapidly, the motors will pull more amps and could trigger a low battery warning, has happened to me a couple of times when the P3 was under 50%-- at 50%, you have five minutes left to get it on the ground -- no more, so take it off fly it around and then you may have 2 minutes to get it on the ground before the battery goes to critical. Get your stop watch out the next time you fly-- and check. There just isn't much room to push a battery under 50%. Close proximity, not too high and not in a wind, those are key if your battery is under 50%.
     
  9. TAZ

    TAZ

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    OK

    Edit: I hit submit when I just typed "OK" before I intended but, considering your following comment was significantly more qualifying and accurate...I think I'll leave it at that.
     
    #9 TAZ, Jul 19, 2015
    Last edited: Jul 19, 2015