I had previously had a crash that was caused by a drop in Vcc.
I couldn't identify the cause of the crash so what I did was change the wiring so peripheral devices wouldn't draw current through the APM but rather through a separate BEC off the main battery.
I repaired the copter and had a couple of flight that went OK, and again today I had another crash.
A sharp drop in VCC but Voltage looks OK (?)
it is another expensive crash as I am flying a heavy hexa but I am trying to identify the cause so I can fix the copter and use it commercially
Any help would be much appreciated,
Thanks
Replies
What battery are you using?
It looks like you are using a 4S battery, when your log starts It's not fully charged at 16.4v with no real load, a fully charged 4S battery should read ~16.8v(no load).
When you takeoff and the current rises (to ~45A?) and voltage drops by ~1.5v that could be normal depending on the weight of your copter, my quad es very light and voltage drops 0.4v at 12A with a 4S bat.
Also you used 750mAh from your battery when your start loosing altitude.
I think you should check that your battery is charging correctly and in good condition.
OK I have absolutely zero experience in copters. I am an APM:Plane guy but since no one replied I decided to take a look anyway.
The VCC drops indeed drasticly at the end of the log, and MID flight. That is the main reason of your crash.
But why do you have voltage drops? This looks like a wiring issue to me. maybe a contact or a solder joint isn't 100%.. Do you use the dreaded deans or XT60 connectors?
Can you post pictures of your wiring?
My suggestion is that you temporary replace the power module with a 5V bec, which you connect to the input headers. Leave JP1 off.
So,
The only thing I power from the APM is telemetry and GPS, everything else is powered from dedicated BEC.
3DR power module powers the APM the jumper is off.
log posted above
I can't find why the VCC drops drastically at the end.