ABNORMALITY MONITORING METHOD/SYSTEM FOR NETWORK

摘要

PROBLEM TO BE SOLVED: To provide the abnormality monitoring system of a network, which can maintain the network management function of a master station unit to a normal state even if a data transmission line is disconnected or a communication means controlling the reception and transmission of communication data becomes an abnormal state. SOLUTION: When the communication function of the network is judged damaged owing to the disconnection of the main data transmission line 11 or the occurrence of the abnormal sate in communication IC 5, CPU 7 informs the master station unit MU of the effect of abnormality occurrence and abnormality information containing a place where abnormality occurs from a slave station unit SU through an auxiliary data transmission line 10 provided in a system different from the main data transmission line 11.