Abstract: An arrangement including an automatic transfer switch, a bypass switch, and mutually cooperable pairs of contacts for electrically connecting the two switches. The entire transfer switch is movable as a unit toward and away from the bypass switch to engage and disengage, respectively, the cooperable pairs of contacts, disengagement of the contacts serving to isolate the transfer switch from the bypass switch and from the power sources and load. The transfer switch cannot be isolated from the bypass switch when the latter is open. The bypass switch can only be closed in a direction which connects the load to the same source of power to which the load is connected through the transfer switch. Each mutually cooperable pair of contacts engage each other solely by friction. There are at least three cooperable pairs of contacts, for connecting the transfer switch to a normal source of power, to an emergency source of power, and to a load, respectively.