关键词: 可编程逻辑控制器(PLC)；真空烘烤；工业以太网通信 

Abstract: The HL-2M vacuum baking system use two PLCs (Programmable logic Controller) to form an 
automatic control system, and compile the corresponding logic program according to the process requirements to 
control each actuator, realize the program adjustment of the system heater electric power, heat exchanger heat load 
and valve opening, and achieve the purpose of baking with a temperature rise gradient of ±2℃. The PLC 
establishes the profinet communication protocol with the valve island, and controls the on-off valves in and out of 
the vacuum chamber and the divertor through address mapping and adjusts the load input of the baking system. 

Key words: PLC, Nitrogen baking, Profinet communication