Low battery alert

Mike Shellim 05 May 2018

Here's a snippet for a low battery alert. It's suitable for both receiver and flight batteries using NiMH or LiPo chemistry. (For LiFe cells I prefer to use a timer.)

The snippet ignores short low voltage spikes by placing a minimum duration on the low voltage before triggering the alert.

In the following example, an alert is triggered when the voltage falls below 7V for 3 seconds, and repeats every 4 seconds until the voltage recovers.

L1: a<x, RxBatt, 7V, Delay(3s)

SF1: L1, Play Sound(Beep 1), repeat(4s)

For flight packs with sensors, use Cels as the first operand in L1.

Sound file for alerts

The code above generates a beep, but of course you could also use PlayTrack to play a custom voice clip. I use this custom sound file for my receiver packs. It plays "receiver battery low". This is more informative than the lowbat or batlow files provided with many sound packs, as they typically only say 'battery low'.