A sprung seat suspension comprising a base frame; a seat carrier frame including height sensor assembly; linkage mounted on the base frame and operative to adjustably, vertically support the seat carrier frame with respect to the base frame and including an actuator which strokes the sensor assembly along a path during vertical movement of the seat carrier frame. A mover is mounted on the base frame and for adjustably vertically displacing the seat carrier frame from the base frame. An extension is connected to the height sensor assembly and the mover for selectively extending the mover. A retractor is connected to the height sensor assembly and the mover for selectively retracting the mover. The sensor assembly comprises a plurality of sensors positioned along the stroke path of the actuator which may be selectively independently activated to selectively activate the extension and retraction as the actuator strokes the sensor assembly.