P4p crtically low battery

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Hey guys im new here but just a quick question, I was flying my p4p and the critically low battery alarm sounded at 15% ( i have my low battery alarm set at 50%)and to return home immediately so i started the manual flight back to home point, the drone being about 300 meters away ( over the ocean ) clear line of site so plenty of battery to do the job. At least 3 times the critically low battery voice/alarm sounded again and STOPPED the drone in mid flight to tell me again it was critically low and taking about 5 seconds to regain control, so 3 - 4 times the drone stopped and hovered using more battery power to resume flight for the home run. Why would dji have a preset like this ? The drone telling me there is just enough battery to return to home yet this preset stops the drone multiple times using vital power to tell me again something i already know. It was VERY frustrating to think my $2000 plus drone may have gone for a swim never to be seen again due to this what seems a preset function for critically low battery. As i said im new to the dji phantom 4 pro so any info would be appreciated. Cheers guys.
 
A couple of things spring to mind and I'm referring to my P4 which I think is similar to the P4P WRT critical battery settings.
Having had a similar experience to yourself, just the one time, you should never still be in the air at 15% and hoping to make it back from that distance. The % indication is not a reliable indication of the battery life and I always have the voltage displayed on the app for a more accurate idea of how much time I have left. You can turn off the smartRTH function in the app so you still have full control over the drone but if it is activated, cancel it to manually bring it back. As I mentioned, try and be on the ground at nothing less than 20% as the numbers on the app, weather conditions will probably cause you grief sooner rather than later.
 
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I agree with everything tevek said in his post, but I would also suggest you get comfortable with checking the cells and battery temp. To make this screen a quick and easy access, I keep C1 programmed to display this battery data screen.
 
A couple of things spring to mind and I'm referring to my P4 which I think is similar to the P4P WRT critical battery settings.
Having had a similar experience to yourself, just the one time, you should never still be in the air at 15% and hoping to make it back from that distance. The % indication is not a reliable indication of the battery life and I always have the voltage displayed on the app for a more accurate idea of how much time I have left. You can turn off the smartRTH function in the app so you still have full control over the drone but if it is activated, cancel it to manually bring it back. As I mentioned, try and be on the ground at nothing less than 20% as the numbers on the app, weather conditions will probably cause you grief sooner rather than later.
I would like to see DJI fly their drone as long as they say it will fly. DJI statement of how long the drone will fly misleads people to fly their quad longer then it show be.
 
I would like to see DJI fly their drone as long as they say it will fly. DJI statement of how long the drone will fly misleads people to fly their quad longer then it show be.
Agreed, DJI numbers are quoted in ideal conditions etc, same as fuel consumption numbers for motor vehicles that can rarely be attained. As mentioned, I run the battery voltage on the app and eyeball the flight timeline to get comfortable with how much time I have left and make sure I'm back on the ground at nothing less than 20%. Once bitten twice shy...
 
Agreed, DJI numbers are quoted in ideal conditions etc, same as fuel consumption numbers for motor vehicles that can rarely be attained. As mentioned, I run the battery voltage on the app and eyeball the flight timeline to get comfortable with how much time I have left and make sure I'm back on the ground at nothing less than 20%. Once bitten twice shy...
I'm back before 20, but play around the yard a bit.

I wonder what is the best speed for good ground coverage and battery power?
 
I'm back before 20, but play around the yard a bit.

I wonder what is the best speed for good ground coverage and battery power?
I fly at 50kph in P mode for best results. There are a number of threads regarding optimum speed vs distance vs battery life and 50kph seems to be the magic number. I did some tests a while ago using both S and P mode and over a given distance and due to the difficulty in keeping the drone nice and straight, ( in S mode), P mode with OA turned off does the trick for me.
 
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I'm back before 20, but play around the yard a bit.
I wonder what is the best speed for good ground coverage and battery power?
With P4P, at full throttle in P mode and sensors on keeps you right about 30mph, which is close to ideal for efficiency. P mode with sensors on also minimizes prop views through the camera at full throttle, but you will see them if you're flying into a wind.

Gadgetguy does 10 mile trips all the time over San Diego's mission bay area, landing at 20 to 15% most the time, typically 23min flight times. He uses P mode with sensors on to optimize his flight efficiency.
 
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What was your altitude? I have heard anecdotally that the critical battery level is dependent on height. I.e. the higher you are, the higher the threshold is.
 
What was your altitude? I have heard anecdotally that the critical battery level is dependent on height. I.e. the higher you are, the higher the threshold is.
Critical battery settings are a hard threshold you input into the app. SmartRTH setting is variable dependent on the 'work' the battery is doing at a given distance. If the battery senses there may be a risk of the drone returning on the available life left to return safely, it flags RTH. You can cancel it as it's quite conservative, although weather conditions often dictate it may be a wise decision.
 
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Critical battery settings are a hard threshold you input into the app. SmartRTH setting is variable dependent on the 'work' the battery is doing at a given distance. If the battery senses there may be a risk of the drone returning on the available life left to return safely, it flags RTH. You can cancel it as it's quite conservative, although weather conditions often dictate it may be a wise decision.
Low Battery RTH Warning and Critical Battery Warning are different things though. I have seen flights where the critical battery warning (and now landing) was triggered at 25% when the aircraft was at ~400 metres height, despite the critical battery warning set to 10%.
 
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Low Battery RTH Warning and Critical Battery Warning are different things though. I have seen flights where the critical battery warning (and now landing) was triggered at 25% when the aircraft was at ~400 metres height, despite the critical battery warning set to 10%.
Yes they are as I mentioned, I have yet to experience a critical battery auto land at anything above the preset threshold. Don't think I want to..... Battery %s are not the most reliable guide to flight time or life remaining and I don't use it exclusively. It may be showing 25% but the battery voltage may be sitting near the 3.2V per cell which is not a good thing given there may be issues with the actual battery in use.
 
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If you have only 15% battery left and you floor it you will probably get a critical battery warning. Look (display) battery voltage with the%, as you deplete your battery the voltage will gradually drop from about 4.25 volts going down to about 3.65% and less (that's low). Your craft need watts (power) which is volts times amps, when the volts drop the amperage (causing more heat) will rise to give you the same watts and that's when your battery can't keep up with demand anymore. I always try to be back at 20%, once in your yard you can putter slowly around a bit more. You don't have to be at 15% to get that warning either, this happened to me just last week, a beautiful sunset and I decide to take a shot, I take out my battery from storage ( around 50%) because I will just go straight up in my yard. Start my P4 and the sun is going fast so I punch it 100% full straight up and at about 200 feet I get the critical battery warning landing! WTF I have a 50% battery, let go off the throttle and all returns to normal. So I try this again to see if I am pushing to hard and it did it again. I laid off the throttle, took my shots and came back down in the 30% range. I know the adds claim 28 minutes but that's probably looking at it hover in your back yard. The most I ever got was 24 minutes. I usually get between 17 and 20 minutes at 30 mph which is over 40,000 feet travel and land at 20%.
 
A couple of things spring to mind and I'm referring to my P4 which I think is similar to the P4P WRT critical battery settings.
Having had a similar experience to yourself, just the one time, you should never still be in the air at 15% and hoping to make it back from that distance. The % indication is not a reliable indication of the battery life and I always have the voltage displayed on the app for a more accurate idea of how much time I have left. You can turn off the smartRTH function in the app so you still have full control over the drone but if it is activated, cancel it to manually bring it back. As I mentioned, try and be on the ground at nothing less than 20% as the numbers on the app, weather conditions will probably cause you grief sooner rather than later.
Yeah cheers for the advice, i do normally have it back before 20% but had to get the shot, now though the shot can wait for the fresh battery. I did cancel the rth to regain manual flight then wondered why it still wanted to do its own thing, bloody scary so as i said the shot or video can wait until the fresh battery is in, thanks again champ foe the response.
 
What was your altitude? I have heard anecdotally that the critical battery level is dependent on height. I.e. the higher you are, the higher the threshold is.
The height was around 20 to 30 mtrs above sea level and home point was a headland about 30 to 40 mtrs high, only a rough guess but id have to check the flight logs. Cheers for the response champ.
 
If you have only 15% battery left and you floor it you will probably get a critical battery warning. Look (display) battery voltage with the%, as you deplete your battery the voltage will gradually drop from about 4.25 volts going down to about 3.65% and less (that's low). Your craft need watts (power) which is volts times amps, when the volts drop the amperage (causing more heat) will rise to give you the same watts and that's when your battery can't keep up with demand anymore. I always try to be back at 20%, once in your yard you can putter slowly around a bit more. You don't have to be at 15% to get that warning either, this happened to me just last week, a beautiful sunset and I decide to take a shot, I take out my battery from storage ( around 50%) because I will just go straight up in my yard. Start my P4 and the sun is going fast so I punch it 100% full straight up and at about 200 feet I get the critical battery warning landing! WTF I have a 50% battery, let go off the throttle and all returns to normal. So I try this again to see if I am pushing to hard and it did it again. I laid off the throttle, took my shots and came back down in the 30% range. I know the adds claim 28 minutes but that's probably looking at it hover in your back yard. The most I ever got was 24 minutes. I usually get between 17 and 20 minutes at 30 mph which is over 40,000 feet travel and land at 20%.
Yeah sounds like that was my issue, critically low and im trying to get it back flat out. Cheers mate.
 
I fly at 50kph in P mode for best results. There are a number of threads regarding optimum speed vs distance vs battery life and 50kph seems to be the magic number. I did some tests a while ago using both S and P mode and over a given distance and due to the difficulty in keeping the drone nice and straight, ( in S mode), P mode with OA turned off does the trick for me.
Thanks for the advice, many helpful answers, cheers i will experiment a bit and see what the results are.
 
If you have only 15% battery left and you floor it you will probably get a critical battery warning. Look (display) battery voltage with the%, as you deplete your battery the voltage will gradually drop from about 4.25 volts going down to about 3.65% and less (that's low). Your craft need watts (power) which is volts times amps, when the volts drop the amperage (causing more heat) will rise to give you the same watts and that's when your battery can't keep up with demand anymore. I always try to be back at 20%, once in your yard you can putter slowly around a bit more. You don't have to be at 15% to get that warning either, this happened to me just last week, a beautiful sunset and I decide to take a shot, I take out my battery from storage ( around 50%) because I will just go straight up in my yard. Start my P4 and the sun is going fast so I punch it 100% full straight up and at about 200 feet I get the critical battery warning landing! WTF I have a 50% battery, let go off the throttle and all returns to normal. So I try this again to see if I am pushing to hard and it did it again. I laid off the throttle, took my shots and came back down in the 30% range. I know the adds claim 28 minutes but that's probably looking at it hover in your back yard. The most I ever got was 24 minutes. I usually get between 17 and 20 minutes at 30 mph which is over 40,000 feet travel and land at 20%.
Punching it at 50% is probably causing the battery to think that's it's not going to make it back, curious to know what the battery voltage was at the time. I've had the smartRTH kick in at 70% (quite a distance from home), started to bring it back and the message disappeared. Turned it around again and the warning came back, so I played that game a lot closer to home and landed at 30%. I usually just leave it turned off for both FPV and Litchi missions as it plays with your mind when trying to focus on flying..
 

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