[17] Circuit symbols for directional control valves (1)

Designations for directional control valves always give firstly the number of ports and then the number of switching positions. Directional control valves always have at least two ports and at least two switching positions. The number of squares shows the number of possible switching positions of a valve. Arrows within the squares show the direction of flow. Lines shown how the ports are interconnected in the various switching positions of the valve. The designations always relate to the normal position of the valve.