Design of an industrial wireless sensor network for process monitoring and PLC control

Abstract

Sensors are used in industry to collect data from the field to regulate and monitor processes. Traditionally, these sensors have been wired from the field to a Programmable Logic Controller (PLC) in a control room, which presents problems such as high cost of installing and maintaining cables and cable trays, as well as the necessity for large panels to house sensor wiring to PLC input-output (PLCs). A wireless sensor network was built for this project to collect sensor data from the field and wirelessly send it to a base station interfaced to a PLC in a control panel. Temperature, pressure, and level are all measured as part of the process. The latency, coverage range, and received signal strength indicator (RSSI), all critical wireless network performance characteristics, are assessed. A user web dashboard is created to visualize sensor readings over time for monitoring purposes. Finally, the data acquired by the sensors at the base station is used to control PLC output devices using ladder logic programming.