PURPOSE: To improve the reliability of this cyclic monitoring device and to attain efficient equipment constitution by organically combining cyclic monitoring device with a disaster preventing monitoring equipment capable of sending detection information from a terminal in accordance with an address call from the receiver side.

CONSTITUTION: A cyclic checking device 9 arranged in each prescribed section of a previously determined cyclic route is connected to a repeater 5 in a disaster preventing monitoring equipment, a CRT control device 8 is provided with a cyclic control part 10 and a cyclic signal obtained when a cyclic operator operates the checking device 9 is detected based upon the access of the repeater 5 from the receiver side 1 and transferred to the control part 10, which executes cyclic monitoring by means of a CRT monitor 14 based upon the cyclic signal transferred from the receiver 1.