Patent ID: 8280653

Claim:
A power distribution system comprising: a plurality of zones; and a plurality of circuit interrupter apparatus, each of said circuit interrupter apparatus being in one of said zones and comprising: separable contacts, an operating mechanism structured to open and close said separable contacts, a trip mechanism cooperating with said operating mechanism to trip open said separable contacts, said trip mechanism including a zone selective interlocking input and a zone selective interlocking output, and a device comprising: a first input electrically interconnected with said zone selective interlocking input, a second input electrically interconnected with said zone selective interlocking output, and an indicator circuit structured to indicate that said zone selective interlocking input occurred at said first input or that said zone selective interlocking output occurred at said second input, wherein the zone selective interlocking output of one of said circuit interrupters in one of said zones is electrically interconnected with the zone selective interlocking input of another one of said circuit interrupters in another upstream one of said zones, wherein the device of each of said circuit interrupters is structured to communicate to a communication network a number of transitions and a number of transition times of said zone selective interlocking input at said first input and said zone selective interlocking output at said second input.