The steps to control the air compressor using Siemens S7-200 PLC (6ES712-1BB23-0XB0) are as follows: hardware configuration Connect the pressure sensor signal to the analog input of the PLC (EM231 module needs to be expanded), and connect the start stop button and overload signal to the digital input terminals (I0.0-I0.7); Connect the contactor coil and alarm indicator light to the output t...