Control arrangement for controlling movement of a differential piston in a hydraulic circuit

A control arrangement for use in a hydraulic control system including a control valve 32 of the type having at least two movable elements (34, figure 1) comprises the step of controlling the positions of the two movable elements such that fluid from a common fluid pressure source is applied to both of the control surfaces of an actuator 50, the control surfaces being of different effective areas, to drive the actuator 50 for movement. The hydraulic circuit may be a closed-loop system in which the control valve 32 and pump are controlled according to the pressures applied to the actuator 50 or the position of the movable elements in the control valve 32. The actuator 50 may be connected via piston rod 60 to a hoist or a hydraulic lifting arm of a work machine or excavator.