Design and implementation of a monitoring system using grafcet

A monitoring system based on a stopwatch automaton is proposed to detect the system faults as early as possible. Each location in the automaton corresponds to a system's situation. Its time space delimits exactly the range of the normal behavior in the corresponding system's situation. The monitoring system detects a fault when the time space corresponding to the actual system's situation is violated. The stopwatch automaton provides a formal foundation to model the system's behavior and to synthesize the exactly time space in each location. This paper aims to provide the grafcet monitor that allows to link the design of the monitoring system of a system with its implementation in a programmable logic controller.