The position of the wiper on the speed-control potentiometer determines the duty cycle of the chopper circuit. When it is fully down, β = 0 (a); when it is fully up, β = 1 (b)
Figure 2. The position of the wiper on the speed-control potentiometer determines the duty cycle of the chopper circuit. When it is fully down, β = 0 (a); when it is fully up, β = 1 (b)