Design and development of a sensor/actuator module to enhance programmable logic controller (PLC) laboratory activities

Abstract

In industry, Programmable Logic Controllers (PLCs) are used to automate industrial processes or machines [1]. Typically, the processes or machines being automated perform a series of steps that require the activation of actuators based on feedback from sensors. PLCs are programmed to carry out these steps or sequences [2]. To effectively teach students how to automate a process or machine using a PLC, an apparatus with a set of actuators and sensors that interact with each other is needed. This paper presents the design and development of a compact Sensor/Actuator Module to be used with an existing PLC trainer. The module will expose the students to four different sensor types that interact with a pair of DC motors with bi-directional drive. The sensor types include inductive proximity, capacitive proximity, retroreflective photoelectric, and through-beam (opposed) photoelectric.