PURPOSE: To prevent an adjusting data storage unit from being left in a device main body and to prevent a set value, etc., from being erroneously changed.

CONSTITUTION: This electrophotographic copying device includes a memory 41 where data for confirming the respective functions and measuring and adjusting the respective parts of the device main body 6 are stored, and is provided with the adjusting data storage unit 40 which is formed to be drawn out and inserted into the device main body 6. In this device, warning circuits 43, 44, 45 and 46 constructed by serially connecting the mechanical switch 44 which is turned on when the unit 40 is inserted into the device main body 6, the switching element 45 which is turned on when the power source of the main body 6 is turned off, the battery 43, the sounding means 46 which is driven by the battery 43 are provided in the unit 40.