The arrows in the box show the flow direction between the valve ports. The circuit function of a valve is symbolized in two rectangular boxes for the de-energized state (right side, visualized by ) and energized state (left). Below are some examples of the most common circuit functions. The circuit function can be expressed in a symbol. More ports or combinations of valves in a single construction are possible.

3/2 way valves can have different functions such as normally closed, normally open, diverting or universal. A 2/2 way valve can be ‘normally closed’ (closed in de-energized state) or ‘normally open’ (open in de-energized state).Ī 3/2 way valve has three ports and two positions and can therefore switch between two circuits.

The specific purpose of a solenoid valve is expressed by its circuit function.Ī 2/2 way valve has two ports (inlet and outlet) and two positions (open or closed). Solenoid valves are used to close, dose, distribute or mix the flow of gas or liquid in a pipe.

“A solenoid valve is an electromechanical actuated valve to control the flow of liquids and gases.” Circuit Functions of Solenoid Valves

1 electric solenoid valve