Hello,
Flew my Quad yesterday and keep getting the “PreArm:Battery 1Low voltage failsafe” warning. Resetting the battery allow me to re-arm the quad and do another flight but keep getting some error messages during the flight and after landing the failsafe prevent me again from re-arm.
Is this due to the temperature been -2C and the battery (a 3S 5000mAH Hen-Ace) exposed to the elements?
Edit: In the Parameter Set Up I have 4 cell. I am not able to change this… Could this be a reason for my issues?
You nearly had the correct settings for 3 cell lipo
BATT_ARM_VOLT,11.0
BATT_CRT_VOLT,10.5 BATT_LOW_VOLT,10.8
Usually you would set these too
BATT_FS_CRT_ACT,1
BATT_FS_LOW_ACT,2
A fully charged 3s should be close to 12.6v, if its dropping to 11.3v before you have even taken off means your batteries are far too cold to fly, you SHOULD NOT attempt to fly with batteries below 15c. they cannot sustain high power loads below that temperature, and at -2c you will be lucky for it to even take off. DJI sell battery heaters for their machine for this reason, their smart batteries wont even switch on if they are too cold.
@geofrancis - today its a lot warmer, probably 6-7C. So I am unsure if temperature is a major issue now. Is 6-7C to cold as well?? (If so, I will consider the heater you linked to…)
Changing the BATT_LOW_VOLT,10.8 setting fixed part of the problem, but not all…
that is still far too cold. your batteries need to be above 15c before you take off, usually once your in the air the constant discharging will keep them warm. if you try and take off with cold batteries the voltage is lightly to plummet immediately, Bypassing the prearm check is lightly to result in a very short flight at best or a crash at worst.
Dont change the battery thresholds, check that the paower brick voltage measurement is accurate.
If the voltage reading is accurate then you have a temperature problem, or the battery is faulty.
At that temperature I just keep my batteries in my pocket before I use them. Or if they’re too big for that I keep them in my vehicle in the sun. It is true that batteries need to be warm, but they will work below 15c. However you need to have realistic expectations of performance when the temperature drops. I don’t start a flight with a cold battery with a full throttle punch. I know my flight times are going to be less. I watch battery voltages very closely, and also watch for voltage sag during high power settings.
Hello everyone,
I have the same error… Could it be a faulty Power Module?
Battery is a 4s 6000 mAh. Sometimes i get battery errors in MP sometimes not. My power module is the standard 3dr power module for apm and pixhawk. It is not the highest quality that’s why i am suspecting that.
I am getting battery failsafe and battery 1 is low error. The quad starts normally and flies without problems but in mid flight these errors appear and it auto lands. It also shows sudden voltage drops, while the battery waws fully charged. I have calibrated them according to ardupilot’s page about the common 3dr power module and it showed normal battery and current readings.
Here are some logs: 2023-07-17 20-35-48.bin (768 KB) 2023-07-17 20-31-18.bin (872 KB)
Thanks for your time
It wasn’t fully charged at the start of the flight. That should be closer to 4.2v/cell, but this is only 4.02. That’s not the bad part, that should still be enough for a flight. Right away the voltage drops to a dangerous level, below 3.2v/cell, and recovers to less than 3.6. I would agree with what @amilcarlucas has said and check the internal resistance. I’d guess that battery is done and needs to be retired.
Thanks for the replies mates! I have another battery like that and i will test them both and see what the readings are on the other one. I was suspecting the power module but as you say the battery might have died as well. Again thank you for your time!
