Implementation of networked control systems using programmable controller based Ethernet network

摘要

This paper presents the implementation of networked control systems (NCS) to be applied in industrial automation by using the programmable controller as the platform controller based Ethernet network. The fast growing in ICT technology on recent era brings some essential progress to support the development of NCS becomes more reliable to be implemented especially for critical delay application in industrial automation. The experiment, which is to measure the delay on the control signal that occur, the control execution accuracy and the cycle time of the programmable controller, had been conducted in four phase from identifying component of NCS and its characteristics, designing NCS, taking simulation of process workflow and simulation of the network and implement to physical system. The delay measure by monitoring the status of communication port of programmable controller. The measurement of control execution accuracy took after observation of process of removing the box from conveyor. The programmable controller's cycle time measurement obtained by capturing the cycle time data from its memory. The experiment results shows that the latest programmable controller along with recent network protocols has capability to deal with the delay and traffic. Delay in the network could decrease the control execution accuracy. The best control accuracy performances occur when total delay in the network are less than 1 s. Thus, the critical delay < 1 s. In other hand, the traffic condition does not have any impact related to the cycle time.