Recently I had a very hard landing with some damages to the legs, the lower battery compartment and the gimbal. Flying with around 40% battery status suddenly it announced "battery voltage critically low " and while trying to get away of the fruit plantation where the Matrice 100 was flying the motors stopped. The result was a hard landing in fortunately soft ground.

I tried to repeat the situation and the result was:

• flying with more than 70% battery status
  

• announcing "battery voltage critically low "
  

• immediate landing
  

The information in the DJI Go App was not consistent:


In principle it's not possible that a battery has a critical low battery warning and having the drone dropping down with 68% battery status.

Back home, I retested the battery. Another inconsitent information:

• the battery had one status LED blinking (meaning the battery is low)
• the App showed no abnormalities, see below
  

Also this is in principle not possible: normal status in the app and low battery indication on the battery itself. Another testflight with anothery battery showed no abnormalities.

Battery status is crucial, and for my work I fly with a Zenmuse XT. A crash will be very expensive! How can I trust in the battery indication? Do I have to expect that my drone is falling down any time from the sky caused by a battery or software defect?

Have you completed any type of firmware update for the battery?  You also have your critical battery warning at 12 percent.  Have you considered a higher percentage?

I keep firmware for M100, camera and RC always at the latest status. I don't know how to upgrade the firmware of the batteries, as I have no direct access to it. I assume that the batteries are upgraded from the drone when connected.

But in any case: no, way that the battery shows 68% level and in the same time the drone makes an emergency landing due to battery voltage critically low, whatever the firmware status is. The information is inconsitent and dangerous! What happened?

solaroebi Posted at 2018-3-7 07:10
I keep firmware for M100, camera and RC always at the latest status. I don't know how to upgrade the firmware of the batteries, as I have no direct access to it. I assume that the batteries are upgraded from the drone when connected.

But in any case: no, way that the battery shows 68% level and in the same time the drone makes an emergency landing due to battery voltage critically low, whatever the firmware status is. The information is inconsitent and dangerous! What happened?

If you have Assistant 2 Software, link the aircraft to the Assistant 2 software. Reset to factory settings and refresh the firmware. From there, restart the aircraft. Do a flight test to see if this issue is continuing. Fly conservatively. If the issue is ongoing, let one of our technicians look at your aircraft.

Assistant 2 Software does not allow me do downgrade the firmware:



Today I had another testflight, without any abnormalities. The problem might be related to temperature, today it was 15 degrees C, the previous flights were around 5 degrees C. The battery temperature was always around 20 degrees C, kept in the house for preheating.

But in any case: no way that I can not rely on the telemetry data! it's just simply crucial and I am afraid of my next commercial flights with the DJI XT. I don't hope the drone will drop from the sky. As precaution I will always fly with 2 batteries, even if one might do it for the mission.

solaroebi Posted at 2018-3-8 05:39
Assistant 2 Software does not allow me do downgrade the firmware:

[view_image]

you ever have this problem again?   i seen it once while idling motors to discharge battery.  Im discharging battery to 5% in order to recalibrate it.