Translations:KAVAN Smart PRO Opto ESCs - Instruction manual/39/en

Set the minimum and maximum speed of the main rotor according to your preference. As soon as you move the throttle beyond the idle position, the engine will slowly spin up until it reaches the target speed. These are calculated by the throttle channel position, where throttle off corresponds to "Minimum RPM" and full throttle corresponds to "Maximum RPM".
Set the Start Acceleration to make the engine start as smoothly as possible. You can set this time up to 60s. Start-up Acceleration is used when the engine is revving from zero speed or when the autorotation rapid exit function is deactivated.
Configure the autorotation rescue time and autorotation acceleration. The autorotation rescue function is used when you need to end autorotation quickly and prevent the model from crashing. In this case, you move the throttle beyond the idle position, "Autorotation Acceleration" is used to spin the engine until it reaches the desired RPM. The "Autorotation Rescue" parameter determines the time after engine shutdown when the autorotation rescue function can be activated. When this time is exceeded, the standard start-up time is used.
Advanced settings: governor gains - (P)roportional and (I)ntegral. You can adjust these gains to fine-tune the governor's response to rapid load changes during flight maneuvers. Please make the changes only in small increments and verify the resulting behavior in a short test flight.
Increase the gain P to remove small speed fluctuations during straight flight, e.g. hovering. If you hear unexpected motor/gearbox noise (indicating rapid oscillation), reduce P gain by 20%.
Increase gain I to maintain precise speed during manoeuvres. If the engine speed starts to fluctuate noticeably, reduce the I-gain by 20%.
In Governor mode, fixed throttle channel endpoints are always used (standard 1.1ms - 1.9ms) and active braking is also enabled.