No buzzer on battery low

I’m using a Pixhawk and latest firmware (AC3.2-rc14) and according to the Wiki a loud beeping should occur if the main battery voltage drops below 10.5 volts for more than 10 seconds.
I could never hear this beeping, although the buzzer is working (it beeps during power on) and the voltage is correctly calibrated.
I did a short indoor flight using an adjustable power supply.
The GCS is telling me “Battery low” but no buzzering even the power supply is down at 9V.
Maybe it has something to do with this issue.

A short LOG and my Setting File is attached.
Could someone please have a look at that ?

the beeps during power on in my APM copter is generated by the ESC…
are you sure your buzzer is working?

Hi, I got exactly the same problem. I tried everything but the buzzer doesn’t work on low battery. When I arm and disarm I get the beeps. I get only a voice message in the mission planner when the battery is low. :mrgreen:

@Gaucho
I’m sure my buzzer is working. When powering the PixHawk by USB only, the ESCs don’t get any power but I hear the beeps directly after power-on (generated by the buzzer) …

kakariki,
There’s no chance that the pixhawk is being powered through the USB connection right? We disable the low-battery failsafe if it’s connected to the USB (because we assume it’s on someone’s bench).
I haven’t looked at your logs yet but I’ll have a peek tomorrow.

@Randy
The logs above were recorded with USB disconnected, but wireless telemetry (3dr radio clone) connected.
That’s also my standard setup for flying outdoors.

rmackay9 your comment:
“There’s no chance that the pixhawk is being powered through the USB connection right? We disable the low-battery failsafe if it’s connected to the USB (because we assume it’s on someone’s bench).
I haven’t looked at your logs yet but I’ll have a peek tomorrow.”

I have the problem with apm2.5, there is no buzzer on battery low even when I disconnect USB. I need it as an essential safety feature for flying. Is there any solution for the problem? The buzzer is working when I arm and disarm. As long as I don’t have a solution I really can’t fly.

I have attached a buzzer to my APM on pin A5. Positive going to the sensor wire, inside pin on the controller and ground to ground. Also, I connected an LED to Pin A4 which goes steady when armed until I go into my Low Voltage then it flashes

Thank you for the answer Joselm. But that is just not working. Everything is correct connected and the buzzer functions because there is an arming and disarming beep. It must be another problem!!

maybe try to go to v3.1.5 where it gives you the option to set the LED_MODE and run your test again. Perhaps there is something wrong with your board? If that works in v3.1.5, then try to upgrade again. According to what I read, it stated that the pins are automatically activated on v3.2. Also, what type of power module do you have ? Make sure it is set up correctly in the failsafe section.

@joselm
Thank you for your reply. That’s just why I updated to V3.2 because V3.1.5 didn’t work. My power module is an APM power module with Deans Connectors Board (SN-BR-0005) and a DF13 6 Position Connector 15 cm (PX4-Con-0016) from 3D Robotics.
Is there any other solution possibility?

@joselm
What does it mean to set up the power module correctly in the failsafe section?

Hi Ulbers,

I would like to help you with this, but don’t have an APM handy to test with this week to confirm the issue. We don’t use these much anymore (I haven’t touched one in a year). Next week I should be able to have a better look. It’s possible that something was missed in the code for this.

He is referring to setting the low voltage/ FS to RTL or Land, in Mission Planner, etc. Then verifying the function in the Planner.

[quote=“ulbers”]@joselm
What does it mean to set up the power module correctly in the failsafe section?[/quote]

Hi Rob,

Thank you very much for investigating in this issue!! I will be keen on your result.

Best regards,
Gerd

@FullScalePilot2

But that has nothing to do with the buzzer as far as I know.

I am referring to the actual low voltage warning in Mission Planner. When you go to fail safe screen it allows you to input the voltage cut off and a reserve mah to activate your fail safe. I have my low voltage set to 10.5 since I am running a 3s lipo and no reserve mah since I do not want the copter to fail safe any action. Also, make sure that in your battery monitor under optional equipment is set up correctly. meaning APM2+ is selected, 3dr power module is selected and I think the 3rd option is as well APM 2+ 3DR module. Look at your HUD and see if it shows you your voltage and current read outs. If it does NOT then perhaps in the parameter list you have the wrong pin set in Mission Planner under battery monitor. I believe on the APM the voltage sense pin is A13 on my settings. I can look when I get home. Those are the only places I know to set up the battery sense and low voltage cut offs and what not.

@joselm
Everything I had done already like you described and is working, except the buzzer!

Back to basics…is the buzzer good? have you tried your led in the buzzer output?

@RabbitStu

The buzzer is good like you can see above!