Usage of RPM Governor (optional)

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Please note that the RPM Governor function is an optional feature and may not be accessible on all MICROBEAST PLUS devices.

When using the governor function for nitro helicopters, during the initialization phase the signal from the throttle channel is passed directly to the throttle servo. When using the governor function for electric helicopters, the throttle is held either at low throttle position or at failsafe position, depending on which position is the lowest (firmware version 4.1.x or higher). In general the RPM Governor can only be switched on when MICROBEAST PLUS is ready for operation. Additionaly you must move the throttle to the low throttle position (or lower) once after initialization phase, in order to unlock the governor.

If you need to move the throttle to full throttle position right after power up, i.e. to program your motor speed controller in electric governor mode, you must deactivate the RPM governor function temporarily at Setup menu point N (firmware version 4.1.x or higher).

Note that if your receiver does not send a valid control signal to MICROBEAST PLUS within two seconds after power up, the throttle channel will be locked for security reasons. In this case [CH5] output will be set to motor failsafe position (set at Receiver menu point N). Only when MICROBEAST PLUS gets a valid signal from the receiver and the throttle stick is moved to the programmed failsafe position (or below) the throttle channel will be unlocked.

With nitro helicopters always ensure that the RPM Governor is disabled when you start the model. Otherwise the RPM Governor would drive the throttle servo up to the full throttle position and stay there as it tries to reach the demanded head speed. So always check the throttle servo position before starting the engine very carefully!


As described above at Governor menu point D set your throttle curves or the auxiliary channel in the various flight modes as high as necessary, so that the desired head speed will be approached and observed. Keep in mind that the head speed should not be higher than 80% of the maximum head speed that is possible with this motor and this gear ratio. If the chosen head speed is too high, the RPM Governor will constantly give full throttle input and no effective govering will be possible because there is not enough room left to open the throttle for compensating the rotor head load.

RPM Display

Since firmware Version 4.2.x there is an integrated rpm display that shows the height of preset rotor head speed when in operation mode. This can be used to additionally check your transmitter setup over Governor menu point D, i.e. when the heli is standing on the workbench with motor disconnected. Using the electric governor function with soft start feature, also you will see the actually measured rotor head speed as soon as the ramp up starts and the rotor speed gets higher than 600rpm.

Caution: Remove all rotorblades, be very careful and keep a safe distance when running the model on the work bench for testing purpose!

RPM display for electric heli governor RPM display for nitro heli governor

When you see the rpm view, the Status LED will be off. A solid Menu LED will indicate the preset head speed, a flashing Menu LED will show the actually measured head speed. After some time without any change, the display switches back to show the tail gyro status (Status LED blue or purple).

Note for using the nitro governor with separate switch channel

Some transmitters offer a special setting that allows to automatically switch the auxiliary governor channel together with the flight mode switch. So the motor can be ignited in the first flight mode and you can spool up the rotor and hover the heli by applying throttle manually. With the second flight mode the throttle curve is a "V"-shaped curve and simultaneously the RPM Governor is turned on by the auxiliary channel. In this case pay special attention that the two throttle curves/throttle positions match as good as possible in the stick point at which you usally switch flight modes. Otherwise the throttle servo would make a jump before the RPM Governor will take over control as you still may be in manual mode for a short amount of time. So in this type of operation it is not possible to activate the RPM governor from idle position and let the rotor spool up autonomously. If you want this, you must activate the RPM Governor before switching to your second flight mode with an additional switch!