I have a PixHawk 2.1 and a Mauch PL series power module with hall-effect voltage/current sensor.
Per instructions, I try to enter the Voltage Divider and Amps/Volt values provided on a piece of paper with my Mauch. However Mission Planner squawks “invalid number entered” on ANYTHING I type into that “Voltage divider (Calced)” field. So no matter what I type in there, it has no effect on the voltage shown on my HUD (which is always 0.6V off from reality) because Mission Planner appears to be ignoring it when it says “invalid number entered” (that is, when I type a number and press tab nether “battery voltage calced” nor “measured battery voltage” change but I simply get this non-descriptive error).
Below shows my settings. The only way to make the HUD show a value remotely close to reality is to manually change “measured battery voltage” to the actual voltage I’m reading from the balance lead of the LiPo. But that goes against the instructions for the Mauch at Power Monitor/Module Configuration in Mission Planner — Copter documentation