LOOP TYPE DATA HIGHWAY FAULT DETECTING METHOD

摘要

PURPOSE:To quickly detect faults of data highway by commonly using the telephone line and transmission line and separating faults from relays of stations and transmission control units. CONSTITUTION:The signal from relay REP is inputted into control circuit CNTA and converted from the digital quantity to analogous quantity. Then, the analogous quantity is transmitted to men and others through the telephone TEL speaker. The voice of man is inputted into CNTA through microphone of TEL where it is converted from the analogous quantity to digital quantity and sent to the next station through REP, thus enabling to exchange telephonical conversation between each station. When there is a fault in ST3 or L2, the signal generated from TEL ST1 can be regenerated by TEL ST2 but not by other TEL ST thereafter. It is therefore possible to determine when there is a fault in ST3 or L2.