Battery Monitors (aka Power Monitors/Modules)


Power Monitors/Modules provide these benefits:

  • Most provide a stable power supply to the autopilot, in addition to monitoring, and therefore reduces the chance of a brown-out

  • Allows real-time monitoring of the battery’s voltage and current and triggering a low battery failsafe

  • Allows compensating for the interference on the compass from the motors using the COMPASS_MOT_x and COMPASS_PMOT_x parameters, see Advanced Compass Setup.

The links below have information about the most commonly used power monitors/modules

Up to 16 batteries/power monitors can be monitored. Each monitor has its own group of configuration parameters, designated by BATTx_ with x denoting each monitor in the system (first monitor “x” is null character, ie BATT_ prefix). In addition, a BATT_MONITOR “type” = SUM is available, that consolidates battery monitors into a single report using the BATT_SUM_MASK.


some kinds of monitors can provide bi-directional battery current information. These are useful when generators or MPPT chargers are being utilized in the system to monitor the net charge state of the battery.

Power Monitors Connecting to AutoPilot Power Monitor Port

CAN/DroneCAN Power Monitors and Batteries

I2C Power Monitor

Power Monitoring Via Telemetry Equipped BLHeli32/S ESCs

EFI Fuel Monitoring

EFI Fuel Monitoring, See Electronic Fuel Injectors section on using BATT_MONITOR = 27 (EFI).

Liquid Fuel Monitors

Substituting a Battery Monitor’s Data into an ESC’s telemetry stream

  • See BATT_ESC_INDEX (for first Battery Monitor. BATTx_ESC_INDEX for others.)


this feature is usually only available as a build option using the Custom Firmware Build Server