Method for detecting failure and slave station for use in same

Abstract

A transmission signal transmitted via a common data signal line, includes a management data region different from a control/monitoring data region including data of control data and monitoring data signals. The slave station acquires input information from an input part corresponding to its own station, acquires control data for reference by an output part of another station in a correspondence relation with the input part from the transmission signal, and obtains a pseudo output change timing equal to a true output change timing of the output part based on the control data. A signal configuring data indicating a first failure state when a time difference between the pseudo output change timing and an input change timing of the input part is smaller than a first threshold value or a second failure state when the time difference is larger than a second threshold value is superimposed on the management data region.