Translations:KAVAN Smart PRO Opto ESCs - Instruction manual/121/en

Warning:

Always use brand new, high quality connectors and make sure that the cables are soldered perfectly. Any possibility of losing connection during motor run represents a risk of damaging your electronics.
If you start the controller for the first time, or make any significant changes in the setup, please make sure that the propeller is removed from the motor shaft.
Always disconnect batteries after the flight session ends. Even if the speed controller is turned off by the switch, it still draws some small current. This could result in a completely drained battery within a few days or weeks.

You can select from multiple basic controller modes:

Normal (ramped) - the preset acceleration curve is always used when accelerating. This is the default mode for normal use.
Fast mode - the selected acceleration time is only applied when spinning from zero RPM. Then the minimum possible delay is applied (0.2 s for zero to full throttle response).
Normal with reverse - behaves similarly to normal mode. In addition, you can select a throttle reverse channel that will control the direction of the motor during flight.
Heli/governor - fast and precise constant RPM control with many adjustable parameters.