Network model based automation of thermal processes using an embedded digital controller

This paper describes the network architectures of both WAN and LAN based real time control and monitoring of thermal process station using an embedded digital controller. The local digital controller is based on a PIC16F877A microcontroller used as temperature controller which directly communicates with the temperature transmitter as well the silicon controlled rectifier (SCR). The internet based control and monitoring operation is realized as PHP scripts along with user developed front panel. The server-client configuration is implemented in Visual Basic Language and uses TCP/IP protocol. The over all time delay due to network based communication has been simulated and compared with the experimental data. The results have shown that the transport delay in internet based communication affects, especially the thermal process insignificantly.