Patent ID: 8004115

Claim:
An automatic transfer switch for automatically switching an electrical load between two power sources, the automatic transfer switch comprising: a switch module; primary and secondary input cords, each attached to said switch module, and each for receiving power from a different one of said two power sources; an output cord, attached to said switch module, for supplying power to said electrical load; and a relay disposed within said switch module and coupled to said primary input cord; wherein said relay is operable to sense a power quality on said primary input cord, such that: when said power quality is acceptable, a state of said relay is electronically controlled by said power of said primary input cord so as to couple said output cord to said primary input cord; and when said power quality is unacceptable, said state of said relay is electronically controlled by said power of said primary cord so as to automatically de-couple said output cord from said primary input cord and to automatically couple said output cord to said secondary input cord.