Abstract: Many industrial applications require variable flow control of fluid (air, chemical gases, water and liquid chemicals). An exhaust blower system based on PLC (Programmable Logic Controller) & VFD (Variable Frequency Drive) is proposed. The main aim is to reduce the energy consumption by the implementation of VFD and hence the proper control of exhaust blower. The PLC operates and commands the variable frequency drive (VFD), to drive the induction motor(IM) with required speed by varying the frequency. In this project we are using VFD for controlling two motors for exhaustion of unwanted dust. Here, PLC is controlling suction mechanism of two different machines with set frequency. Whenever suction rate is slower/off, feedback is given to the PLC then, as per the programming, VFD will reduce the frequency of exhaust motor which will ultimately leads to less energy consumption.

Keywords: PLC, VFD, Induction Motor, Energy consumption, Proximity switch, Star–Delta system.