AN ISOLATION SWITCH FOR ELECTRIC POWER SYSTEMS

The movable conductors of a three-phase isolation switch are incorporated into the electrically insulative molded shaft, thereby mechanically supporting them and isolating them from the metal axle of the shaft. Movable contacts on the ends of each movable conductor are angularly spaced by .alpha.degrees, where .alpha. is less than 180.degree. and is 90.degree. in the exemplary embodiment. A common fixed load contact is located angularly between, and spaced .alpha. degrees from, both the fixed line and ground contacts so that the shaft is rotated only .alpha. degrees between a first, closed position, in which the movable conductors connect the fixed load contact for each phase to the corresponding fixed line contact, and a second, grounded position, where the fixed load contact of each phase is connected by the movable conductor to the corresponding fixed ground contact.