Abstract: The design of centralized temperature control systems for tandem extrusion systems was discussed, and a method to realize the communication between Siemens S7-300 and temperature control instruments was presented. By this way, the temperature of tandem extrusion systems can be controlled in integrity so that the production process can be managed smoothly and the technical data can be recorded and archived. This communication mode has the merits of fast response, simple software design and low cost.

Key words: tandem extrusion, programmably logic controller, temperature control instruments, communication