To realize quick response at a center monitor by a constitution wherein each field processor monitors abnormality of data and transmits a specific data to a center monitor through a communication processing section and the data collected over a long term is recorded along with the history of abnormality of data or apparatus.

A field processor 3 comprises a main processing section M and a communication processing section S provided, respectively, with CPUs 6m, 6s. At the main processing section M, data from a measuring apparatus group 7a and an abnormality detection unit group 7b are captured by input means 8a, 8b and processed by a data reading means 9 before being recorded on a nonvolatile recording medium 11 through a recording medium read/write means 10. When a decision is made that the data is abnormal, based on the correction and operation performed at a data processing means 12, it is alarmed to an abnormality processing means 13 and a relevant data and the like are recorded in a memory means 14 before requesting the communication processing section S to notify the abnormality to a center monitor 4. The monitor 4 presents the content of abnormality on a display means and an alarm is delivered from an alarm means, according to need.