ZSK type speed switch I. Overview ZSK type speed switch is a mechanical type speed signal device can output four groups speed contact signal for automatic control and protection unit. Device mounted on top of the generator, matching a 10-tooth chainring and eddy current speed sensor, speed meters for electrical supply. Second, the technical parameters of movement speed range: 60r / min ~ 1400r / min speed action precision: ± 3% of rotation direction: forward (clockwise) or reverse (counterclockwise) contact number: 4 Group SPDT contact capacity: 5A / AC220V 0.5A / DC220V