Design and Application of a Non-wrapped Programmable Logic Controller (PLC) Laboratory Kit for Automatic Control Education

Programmable Logic Controller (PLC) is widely used in various fields and is an essential practical training for college engineering education. However, traditional PLC platform suffers from black box effect and low portability. In this study, a non-wrapped PLC laboratory kit is designed and tested for automatic control education. The laboratory kit is composed of PLC, man-machine interface, input and output elements, which are much more portable and flexible than elements of traditional PLC platform. The input elements mainly include buttons, encoder, temperature sensor, weight sensor and proximity switches, and the output elements are mainly indicator lights, lead screw slides driven by stepper motors, three-phase motor controlled by frequency converter, and electric heater controlled by solid-state relays, and servo motor. The basic practice projects, controlling practice projects, and innovative practice projects developed on the base of the laboratory kit can promote students’ practical ability and meet the teaching requirements of automatic control education. Moreover, the application of the laboratory kit could improve students’ wiring operation ability (overcoming black box effect that traditional PLC training brings), cultivate students’ design and problem-solving ability. The designed laboratory kit is intended for third-year students at Xi’an Jiaotong University.