Page 84 - PNEUMATIC SYSTEM INSTRUMENT

Directional valves also can be remotely shifted with air or electricity.

In air-operated valves, pilot pressure is applied to the spool ends or to

separate pilot pistons. In electrically operated valves, a solenoid

responds to an electrical signal (AC or DC, depending on design) and

physically displaces the valve’s moving member.

Solenoid actuation is perhaps the most common way to shift

pneumatic directional valves because electrical and electronic

controls for so many other machine actions are readily available and

popular. These controls can easily integrate the air-valve solenoids for

sequencing and automation.

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