| 摘要 |
<p>PROBLEM TO BE SOLVED: To restart communication with a regular station where communication is normally executed by easily discovering a communication abnormal place in a network. SOLUTION: The regular station S3 is provided with a terminal end resistance R, change-over switches SW1 and 2, a change-over relay RY, a communication processing part S31 and a display part S32. In a regular state, the change-over switches SW1 and 2 are in an off-states and a communication transmission path C and the terminal end resistance R are in a non-conductive state. In the meantime, the change-over relay RY is in the on-state and the transmission path C is in a connected state. When communication abnormality is detected in the network, a control station M transmits a command to respective regular stations. Then, the communication transmission path C and the terminal end resistance R are made in the non-conductive state, the change-over relay RY is changed-over into the off-state, the transmission path C to the succeeding one is made the non-connecting state, subscription poling is transmitted while turning-off the terminal end resistance R in order from the regular station nearest to the control station M, the regular station where communication is normally executed is detected and communication is restarted.</p> |
