Abstract: A switch apparatus usable in a DC circuit employs a rotatable shaft having conductors that are removably connected with two or more pairs of contacts that are situated on line conductors and load conductors and that are connected in parallel by the conductors on the shaft. In rotating the shaft to open the switch, one pair of the contacts is electrically disconnected prior to electrical disconnection of the other pair of contacts. Further rotation of the shaft causes the other pair of contact to eventually become disconnected. Electrical arcs thus form only at the air gaps between the other pair of contacts and the conductor. Magnetic field elements in the form of permanent magnets are situated in the vicinity of the air gaps of only the other pair of contacts and apply Lorentz forces to the arcs to extinguish them.

Abstract: A switch apparatus usable in a DC circuit employs a rotatable shaft having conductors that are removably connected with two or more pairs of contacts that are situated on line conductors and load conductors and that are connected in parallel by the conductors on the shaft. In rotating the shaft to open the switch, one pair of the contacts is electrically disconnected prior to electrical disconnection of the other pair of contacts. Further rotation of the shaft causes the other pair of contact to eventually become disconnected. Electrical arcs thus form only at the air gaps between the other pair of contacts and the conductor. Magnetic field elements in the form of permanent magnets are situated in the vicinity of the air gaps of only the other pair of contacts and apply Lorentz forces to the arcs to extinguish them.

Abstract: A switch apparatus usable in a DC circuit employs a rotatable shaft having conductors that are removably connected with two or more pairs of contacts that are situated on line conductors and load conductors and that are connected in parallel by the conductors on the shaft. In rotating the shaft to open the switch, one pair of the contacts is electrically disconnected prior to electrical disconnection of the other pair of contacts. Further rotation of the shaft causes the other pair of contact to eventually become disconnected. Electrical arcs thus form only at the air gaps between the other pair of contacts and the conductor. Magnetic field elements in the form of permanent magnets are situated in the vicinity of the air gaps of only the other pair of contacts and apply Lorentz forces to the arcs to extinguish them.

Abstract: A switch apparatus usable in a DC circuit employs a rotatable shaft having conductors that are removably connected with two or more pairs of contacts that are situated on line conductors and load conductors and that are connected in parallel by the conductors on the shaft. In rotating the shaft to open the switch, one pair of the contacts is electrically disconnected prior to electrical disconnection of the other pair of contacts. Further rotation of the shaft causes the other pair of contact to eventually become disconnected. Electrical arcs thus form only at the air gaps between the other pair of contacts and the conductor. Magnetic field elements in the form of permanent magnets are situated in the vicinity of the air gaps of only the other pair of contacts and apply Lorentz forces to the arcs to extinguish them.

Abstract: An enclosed switching apparatus includes an enclosure and a primary power supply disconnect mounted in the enclosure. The primary power supply disconnect has first and second terminals, the first terminals are electrically connectable to a primary power source and the second terminals are electrically connectable to a load. An auxiliary power supply unit includes an auxiliary power supply disconnect having third and fourth terminals. The third terminals are electrically connectable to the primary power source. A transformer has fifth and sixth terminals, the fifth terminals are electrically connected to the fourth terminals of the auxiliary power supply disconnect. An auxiliary fusible element has seventh and eighth terminals, the seventh terminal is electrically connected to one of the sixth terminals of the transformer. A receptacle has ninth terminals thereon. One of the ninth terminals is electrically connected to the eighth terminal of the auxiliary fusible element.