An electrophotographic printing or copying machine includes a functional
module which can be readily removed and replaced by service personnel.
The module includes a monitor in the form of an electronically-readable
memory, which includes information about how the particular module is to
be operated. A distribution board electronically accesses the memories
within the monitors and reads therefrom information, such as how much
voltage to supply to different components within each module. The
distribution board can also update the number of prints made with each
module, and maintain this count within the monitors.