Luminaire diagnostic and configuration identification system

A diagnostic and configuration identification system (40) for an electrical device and a photocontroller (10) which automatically turns the electrical device on and off in response to ambient light levels. A detector (32) senses the load drawn by the electrical device when it is on. A processor (54) is responsive to the load drawn by the electrical device when it is on and programmed to detect a cycling fault condition based on the load drawn by the electrical device and to provide an indication of a cycling fault condition according several possible programming configurations. When no cycling or other fault condition is detected, the processor (54) determines the cycling fault condition indication configuration and then outputs a code signal indicative of the programming configuration.