Hi Frans.
In the section below you describe PWM with a pulse width of less than
100% - thus running the motor at less than full speed.
This surprises me as electric full speed pitch change is slow compared
to hydraulic pitch change already.
Is there ever a reason to slow the electric motor down?
> Furthermore, in the application of Woodcomp propellers with either
> feathering or resversing options, it isn't actually DC which is fed to
> the controller. The controller uses PWM (Pulse Width Modulation) to
> control the prop, and it is the ratio between the pulses and pauses that
> determines how fast the pitch changes. This pulsing DC behaves, as far
> as the micro-switch is concerned, exactly as AC, because the DC is
> interrupted periodically and any arc when opening will extinguish in a
> few milli-seconds.
> So, in this application with PWM you can use the micro-switches to their
> max AC-current rating. The lower max DC-rating doesn't apply here.
>
Jan
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