Design of PLC networks using remote I/O module based on controller area network

The design of the networks system through a controller area network (CAN) bus is presented. To distribute the control points with a long distance and located for the application to on-off electrical equipment by the remote I/O module. The controlling and communication between the programmable logic controller (PLC) and the remote I/O modules are used by the CAN bus serial communication. The experiment has been set up with the maximum of 32 remote I/O modules. Each remote I/Os are linked to the host PLC programmed for handling an interrupt request from any remote I/O independently. Therefore, the scanning time of the controller is not affected. By using this technique, the controller (PLC) can be efficiently applied to several hundred meters.