Pixhawk, 3.1.5, no alarm on low batt fail safe

Hi Gang,

I went flying this weekend and after a little while my 3DR 2014 DIY Quad went into Land mode. Thinking it was low battery I walked up to my Quad thinking I would hear the low battery chimes, I didn’t hear anything (not from Pixhawk or my low battery sensor) so I assumed some other problem. I hooked up my Telemetry unit and did not see any error so I started to fly again, again it went into Land mode with no sounds. After looking at the logs it definitely was low battery fail safe.

First off, what would cause no sound? When arming, disarming I can hear sounds, I assume that uses the speaker so I know it was connected.

Secondly, if I change battery size (i.e. switch from 6000mah to 4000mah) do I need to adjust anything in Mission Planner?

droneshare.com/mission/5316

It happened again tonight, I ascended and suddenly it became really difficult to control (Land mode?)

Battery Monitor Readings
1 3.68
2 3.70
3 3.68
4 3.68

Total 14.7
arduplotter.com/view/53967cd4817 … 769c#power

I also took some snapshots of my settings, do I have this configured correctly? I have the APM Power Module Connected

[attachment=1]Screen Shot 2014-06-09 at 8.04.55 PM.png[/attachment]

[attachment=0]Screen Shot 2014-06-09 at 8.04.55 PM.png[/attachment]

From the log, does this mean I was flying for 23 minutes? Doesn’t seem accurate.

[attachment=1]Screen Shot 2014-06-09 at 8.33.13 PM.png[/attachment]

Also, I think this may be my problem, sensor was set to other. I have re-ran through the wizard.
[attachment=0]Screen Shot 2014-06-09 at 8.04.37 PM.png[/attachment]

I am still wondering if I can get other feedback as I am merely assuming these as I do not know the code as well as others.

So…should I consider my unit faulty? Return it to 3DR? I will open a ticket with 3DR Support.

The key is two have the Sensor setup correctly, apparently the Pixhawk low battery gets triggered from this. Thanks Santiago (3DR Support) for helping with this.