[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.