Current sensor calibrator

This calculator will allow you to calibrate your current sensor better than with the mAh charged vs mAh consumed method.

You need a current meter and a way to see what current and throttle percentage the FC reports (the OSD is a good way to do this).

The steps to follow are:

0. Make sure you have capacitors on ESCs so the measurement will not be influenced by errors from ESC noise.
1. Set BATT_AMP_PERVLT=100 and BATT_AMP_OFFSET=0.
2. Power your plane with propellers on and a current meter connected between FC and pack.
3. Arm and run the motor in manual mode. For four different throttle positions, note down: The throttle position (from the OSD), the reported current (from the OSD), and the actual current (from the current meter). The best throttle positions to use would be 25%, 50%, 75% and 100%. Do not check current on idle as this will be inaccurate.
4. Enter the values below, and the calculator will give you the proper BATT_AMP_PERVLT and BATT_AMP_OFFSET values that you now need to write to your plane’s parameters.

(Many thanks to mfoos for writing this note.)

Last updated on December 27, 2025. For any questions/feedback, email me at hi@stavros.io.