ESC calibration¶
Most models of PWM based ESC need to be calibrated to ensure that all the ESCs respond to the same input with the same speed. To calibrate them they need to receive maximum PWM input when initially powered on, then receive minimum PWM input when they have beeped to indicate that the maximum has registered.
Warning
You must remove all propellers from your vehicle before doing any ESC calibration. Calibrating with propellers installed is dangerous.
ESC Calibration Procedure¶
This process uses the Q_ESC_CAL parameter to enable ESC calibration in QSTABILIZE mode. There are two modes of operation available:
with Q_ESC_CAL=1 the output to the motors will come directly from the throttle stick in QSTABILIZE mode when the vehicle is armed
with Q_ESC_CAL=2 the output to the motors will be full throttle when the motors are armed
The process when using Q_ESC_CAL=1 is
remove your propellers for safety
power up just the flight board and not your motors. If you don’t have the ability to isolate power to the ESCs when on battery power then power up your flight board on USB power
set the Q_ESC_CAL parameter to 1
change to QSTABILIZE mode
set the safety switch off to activate the outputs
arm your aircraft. The PWM output on all quad motors will now be controlled by your throttle stick
move the throttle stick to maximum
add power to your ESCs by connecting the battery
wait for the ESCs to beep to indicate they have registered the maximum PWM
lower the throttle stick to zero and disarm your aircraft
you should hear a beep from your ESCs to indicate they have registered the throttle range
The process when using Q_ESC_CAL=2 is
remove your propellers for safety
power up just the flight board and not your motors. If you don’t have the ability to isolate power to the ESCs when on battery power then power up your flight board on USB power
set the Q_ESC_CAL parameter to 2
change to QSTABILIZE mode
set the safety switch off to activate the outputs
arm your aircraft. The PWM output on all quad motors will now be at maximum
add power to your ESCs by connecting the battery
wait for the ESCs to beep to indicate they have registered the maximum PWM
disarm your aircraft
you should hear a beep from your ESCs to indicate they have registered the throttle range
Note that using Q_ESC_CAL=1 can be useful for testing your motors response. This is the only mode when you are able to directly control the throttle level on all your motors at once. While in this mode you can use a laser tachometer to test your motor speeds at different throttle levels if you have one.
Warning
Be sure to set Q_ESC_CAL back to zero after calibrating for normal operation