PURPOSE: To automatically collect data without fail by detecting whether a data collecting condition is satisfied or not, and collecting the data when the condition is established.

CONSTITUTION: Since a remote console 400 as the data collector is connected through MODEMs 3051 and 3052 to a public line 303 and plural controllers 1001-100n are connected to the public line 303, the remote console 400 can collect the data from the respective managers 100. In this case, it is detected whether the data collecting condition is satisfied or not, and when the condition is established, the data are collected. Thus, the data can be automatically collected without fail.