Immediate low battery alarm.

[JLeith]

I am trying to convert a Droidworx AD-8 HL with a Microkopter controller to an AD-6 HL with a DJI Wookong controller. I am using the same motors and batteries with Afro ESCs. The problem is that as soon as I take off the low battery cuts in and it lands again. The telemetry shows a 3.5v drop when it takes off. Does anyone have any idea what I need to change?

The spec for what I am trying to fly is –

Spektrum AR8000 Receiver with T1000 telemetry module
DJI Wookong controller with iOSD
6 X AFRO 30A ESCs
6 X AXi 2814/22 motors
6 X APC 12 X 3.8p Props
2 X 4s Zippy 8000 batteries

Any help gratefully received.

All the best
John

 

[rilot]

I would check all of your connections and batteries. A 3.5V drop is mental and points to something wrong. Do you have per-cell telemetry to identify if it's a cell gone bad?

 

[JLeith]

Thanks for the reply. I don't have per cell telemetry but I have a second set of batteries and it happens with them as well. The internal resistance of the batteries is between 15 and 20 milli ohms which seems good enough.

 

[rilot]

Have you tried with just one battery? It could be your Y harness going bad or something. I'm fairly confident that a voltage drop that high is going to be a solder joint or connector somewhere.

 

[CdA D]

Check your low battery settings in the assistant. Are you getting the flashing yellow or red warnings?

 

[JLeith]

I'm getting the flashing yellow light and then almost immediately the flashing red light. The battery settings are set to 15.2 volts which is 3.8 volts per cell for a little safety margin whilst I'm testing. The problem seems to be that there is the 3.5 volt drop on takeoff and when the machine is flying which then recovers when the motors are turned off again.

 

[Carapau]

Have you calibrated the voltage meter in the Assistant software? To do this you need to plug in your battery and connect to the WKM and then in the Assitant software under the voltage tab click on the calibration tool. Use an external voltmeter to read the battery's voltage and then just enter that into the Assistant calibration screen.

 

[CdA D]

As Carapau said, Calibate the voltage in the Assistant Software. Then try setting your loss to 4.00v.

 

[JLeith]

I've done the calibration but won't allow a loss that high to be set. I'm beginning to wonder if I have a problem with the power to my ESCs.