PURPOSE: To improve the crime preventing preservation management such as the forgetting of cutting-off the electric power sources of a variety of electrical equipment and forgetting of closing a crime preventing shutter by connecting a variety of electric equipment in a building with a variety of locking devices through interlocking.

CONSTITUTION: A variety of electrical equipment 12 such as air conditioner 12a installed in a building 1, lighting device 12b, elevator 12c, and a crime preventing shutter 12d are connected with a locking device 11 through a switch 13 equipped with an electromagnet (magnet coil) 13a. An electric power source for the above-described electrical device 12 is ON/OFF-operated by inserting a tenant key 10 into the locking device 11. A prescribed magnetic card 4 is inserted into a magnetic card reader 14 installed in a key box 7, and read by the card reader 14, and the correctness of registration of the magnetic card 4 is judged, and when the collation of registration accords, the opening/closing door 8a of the above-described key housing depository 8 is opened according to an instruction supplied from a management controller 5.