Position Switch

Written by Jerry Ratzlaff. Posted in Pressure Instrument

A position switch provides a discrete input to the PLC. The position switch is used to confirm the position of a critical component in the process, often a valve.  In processes where valve closure is important, such as during a mixing process, ensuring that the valve is closed is important.

Note that like a pressure switch, a position switch's sole function is to provide a binary TRUE or FALSE into the PLC.

  • Abbreviated as ZS

Types of Position Switches

Configuration and Alarms

Alarms in the PLC can be:

  • ZSO - Position Switch Open
  • ZSC - Position Switch Closed
  • ZSHL - Position Switch High Low