MONITORING DEVICE

PROBLEM TO BE SOLVED: To provide an inexpensive monitoring device which can more efficiently transmit information between a monitoring center and each object to be monitored. SOLUTION: A monitoring device is provided with one or more buildings B each of which is equipped with a device 2 to be monitored by means of the main body 1 of the device and a monitoring sensor C equipped with an integrating device 3 connected to the main body 1 in each building B through a communication line 4. The line 1 has such a function that transmits an alarm signal to the integrating device 3 when the main body 1 in one building B detects the abnormality of the device 2 to be monitored and enables persons staying in the building E to speak with persons staying in the center C.