Finally lost my bird after 9 months of great no issues flying.
- Thread starter Waba waba
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- crashed cutoff low voltage
Your crash was not a factor of the battery's health (cycle count) but rather a factor of its state of charge, temperature, & the power demand requested when you lifted off.
Be careful.. See the other threads on what percentage to bring them down to.. It's in the single digits and I've seen a range of answers. But I also believe I read in this forum that bringing it literally to 0% (no voltage ) is fatal for the lipo battery (and if so, ideally the firmware would shutt off the demand before that happens but I've never read that it does). Just make sure to research it well so you know what you should do (and also allow for error in the reading, eg 1% or 2% could easily be way too close to 0)... But check the other threads.. And reply 24 above (vs my speculation).
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To avoid situations like this is the reason I created the quick reference table in this thread:
Phantom 3 Battery Characterization
From my battery characterization you can see the Phantom 3 percentage is incorrect after taking to the air, it misjudged the initial capacity of the battery, which is very difficult to determine on a partially discharged battery. The voltage at the start was around 16V which would be around 60-90% charge, hard to determine until you load the battery. After you started flight it quickly dropped to around 14.4V, which is 20% or less of battery capacity. I have read you can slow the rate of descend in auto land by applying full up throttle....although the below data makes it look like it fell from the sky....
Check the chart below that shows altitude, battery voltage, and the 20% voltage. All others should watch out for this....especially when you first takeoff.....
Phantom 3 Battery Characterization
From my battery characterization you can see the Phantom 3 percentage is incorrect after taking to the air, it misjudged the initial capacity of the battery, which is very difficult to determine on a partially discharged battery. The voltage at the start was around 16V which would be around 60-90% charge, hard to determine until you load the battery. After you started flight it quickly dropped to around 14.4V, which is 20% or less of battery capacity. I have read you can slow the rate of descend in auto land by applying full up throttle....although the below data makes it look like it fell from the sky....
Check the chart below that shows altitude, battery voltage, and the 20% voltage. All others should watch out for this....especially when you first takeoff.....
Waba,
I have been trying to recreate a poor battery assessment by the Phantom 3 such as this and failed. I have been leaving my batteries for maybe 2 days and they still read low. Can you please look at your earlier flight on the same battery and tell me the below information or even better yet, attach the .csv file for that previous flight....would still have to know when you original charged it and when you flew the first time and when you flew the second time to understand the timing of everything...also, how many days do you have your battery set to discharge in....
Flight 1:
Date and time battery was charged:
Starting percentage:
Ending percentage:
Flight Time:
Date and time flight started:
Date and time flight ended:
Flight 2 that contained the incident:
Starting percentage:
Ending percentage:
Flight Time:
Date and time flight started:
Date and time flight ended:
Thanks!
I have been trying to recreate a poor battery assessment by the Phantom 3 such as this and failed. I have been leaving my batteries for maybe 2 days and they still read low. Can you please look at your earlier flight on the same battery and tell me the below information or even better yet, attach the .csv file for that previous flight....would still have to know when you original charged it and when you flew the first time and when you flew the second time to understand the timing of everything...also, how many days do you have your battery set to discharge in....
Flight 1:
Date and time battery was charged:
Starting percentage:
Ending percentage:
Flight Time:
Date and time flight started:
Date and time flight ended:
Flight 2 that contained the incident:
Starting percentage:
Ending percentage:
Flight Time:
Date and time flight started:
Date and time flight ended:
Thanks!
After reading all these lost copters and falling out of the sky experiences, ya gotta wonder if there is something in the software to generate recurring revenue.....
This seems counter intuitive given outcome would likely be reliability reputation damage and the attendant costs of warranty work/replacement.After reading all these lost copters and falling out of the sky experiences, ya gotta wonder if there is something in the software to generate recurring revenue.....
Sounds like dji badly needs to work on their state of charge algorithms! This should not be happening, partly discharged pack or not...
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Is that your GTR you were filming? If yes, go buy another Phantom!
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Ok so I did some further look on Healthydrones and noticed my batteries were label different on the site. The battery that went down was my 2nd battery. Going back a few flights it look like it had a bad cell. Another thing I have noticed is that my 3rd battery too is look suspect too and it has been used the least . Now my first battery is showing green all over and has been used the hell out of it..hmmm more investigation being done since family is gone for a few hours. I appreciate all the replies back to guys. I will definitely be check my flights data on healthy drones more often now.
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No it was not, mine was at home on my wallpaper
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- Joined
- Jan 24, 2016
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- 378
- Age
- 46
Haha. My brother has one Nismo GT-R... One of the few!
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Thanks, and do you know when you charged the battery and how many days your autodischarge setting is at? It look like on that flight it put you at 96% battery but I think you were only at maybe 70% battery...
All batteries were charged the night before since I knew I was going to work by the beach in the morning. I have them set to auto discharge after 2 days. Thanks for the help
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Newb here n hope it's ok to ask this question here. Say I flew d bird for a while n had say 75% in my bat...I shud charge it to 100% for my next flight tomorrow? Tks.
If your having a day in between flights yes..
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Comparing those .csv has been very interesting....the charge in capacity determined by the Phantom and my calculations by doing current integration agrees, but seems to indicate that you only had 36% battery at the start of your first flight. The voltages under load show it was less than 100%, although the data shows it near 100%, but not that low. The voltage decay does not match my example flights, it seems to stay flat. Also, on my example flight voltage and percentage correlate with a R^2 of near .9 and yours is less than .01. How may charges did you have on that battery? Do you have any idea what the cell difference is between cells? That would be in the .dat files if you feel like retrieving them. It looks like the battery life was at 85%....puzzling....
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