UNIT IDENTIFICATION SYSTEM

PURPOSE:To improve maintenance by reducing management man-hours, preventing mis-mounting, and contriving free replacement of circuit units on the extension or maintenance. CONSTITUTION:In an electric device on which plural numbers of the same circuit units 1-4 are mounted, each of the circuit units 1-4 is provided with each of adder circuits 11-41 from which an output adding 1 to an input is obtained and the adder circuits 11-41 provided to the plural circuit units 1-4 in the electric device are connected in series. Thus, a unit identification number is obtained automatically depending on a mount position to the electric device. Thus, identical circuit units are used for the plural circuit units.