| 摘要 |
PROBLEM TO BE SOLVED: To provide a monitoring system with which line quality can be maintained while reducing cost for routine alarm issue. SOLUTION: This monitoring system is provided with transmission side communication equipment 100 for performing dialing by forming a DC loop circuit on a telephone set for performing routine alarm issue in the monitoring system using the caller number reporting service of the telephone line and for finishing a telephone call by opening the DC loop circuit after waiting for prescribed time and reception side communication equipment 200 for returning a primary response signal by forming the DC loop circuit on the telephone line when the polarity of the telephone line is inverted, for returning a reception complete signal by opening the DC loop circuit when a caller number report is received, storing caller number data in an alarm re-issue confirmation processing area when there is call incoming ringing and recognizing the routine alarm issue when there are not the same data in this area. This economical burden can be reduced.
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