PURPOSE: To improve the accuracy of an automatic test and to improve the reliability of an automatic exchange, by providing an artificial fault subscriber line and an artificial subscriber circuit, and testing them, and verifying the function of a testing device.
CONSTITUTION: The automatic exchange connects the subscriber testing device ALT to artificial fault subscriber lines FL1∼FL4 to take a test prior to a test of each subscriber line SUB using the device ALT, inspecting whether a fault is detected accurately or not. Further, a subscriber circuit testing device ACT is connected to artificial fault subscriber circuits FC1∼FC3 successively to take a test prior to a test of a subscriber circuit LC using the device ACT, inspecting whether a fault is detected securely or not. After said verifying tests are completed and the normalcy of the devices ALT and ACT is confirmed, an actual test of the subscriber lines SUB and subscriber circuits LC is taken.
ISHIKAWA HIROSHI
ISHIGURO TAMAHIKO
