Abstract: A protection relay for an electrical switching apparatus for a load includes a number of voltage sensors structured to sense voltage applied to the load, a number of current sensors structured to sense current flowing to the load, and a processor cooperating with the number of voltage sensors and the number of current sensors. The processor determines a fault current available at the load. An output cooperates with the processor. The output is structured to output the determined fault current and a number of: incident energy at the electrical switching apparatus, and a personal protective equipment level operatively associated with the electrical switching apparatus. The processor determines from the determined fault current the number of: the incident energy at the electrical switching apparatus, and the personal protective equipment level operatively associated with the electrical switching apparatus.

Abstract: An electrical switching apparatus includes a number of separable contacts, an operating mechanism structured to open and close the separable contacts, a number of sensors structured to sense at least current flowing through the separable contacts, and a processor structured to cooperate with the operating mechanism to open and close the separable contacts. The processor determines a fault from the sensed current flowing through the separable contacts. The processor further responsively opens the separable contacts if the sensed current associated with the fault is less than the interrupting rating of the electrical switching apparatus. The processor keeps the separable contacts closed and waits for another circuit interrupter to interrupt the fault if the sensed current associated with the fault is greater than the interrupting rating.

Abstract: A protection relay for an electrical switching apparatus for a load includes a number of voltage sensors structured to sense voltage applied to the load, a number of current sensors structured to sense current flowing to the load, and a processor cooperating with the number of voltage sensors and the number of current sensors. The processor determines a fault current available at the load. An output cooperates with the processor. The output is structured to output the determined fault current and a number of: incident energy at the electrical switching apparatus, and a personal protective equipment level operatively associated with the electrical switching apparatus. The processor determines from the determined fault current the number of: the incident energy at the electrical switching apparatus, and the personal protective equipment level operatively associated with the electrical switching apparatus.

Abstract: A controller for a load includes separable contacts, an operating mechanism structured to open and close the separable contacts, a processor circuit cooperating with the operating mechanism to open and close the separable contacts, and an output controlled by the processor circuit. The output is structured to cause a remote circuit interrupter to open a power circuit electrically connected in series with the separable contacts. The processor circuit is structured to detect failure of the controller to control the load and activate the output.

Abstract: An electrical switching apparatus includes a number of separable contacts, an operating mechanism structured to open and close the separable contacts, a number of sensors structured to sense at least current flowing through the separable contacts, and a processor structured to cooperate with the operating mechanism to open and close the separable contacts. The processor determines a fault from the sensed current flowing through the separable contacts. The processor further responsively opens the separable contacts if the sensed current associated with the fault is less than the interrupting rating of the electrical switching apparatus. The processor keeps the separable contacts closed and waits for another circuit interrupter to interrupt the fault if the sensed current associated with the fault is greater than the interrupting rating.

Abstract: A partial discharge sensor includes a first current transformer having an opening. A conductive shield is disposed within the opening of and proximate to the first current sensor. The conductive shield has an opening. The concentric openings of the first current sensor and the conductive shield are structured to receive a first medium voltage power conductor. A second conductor is electrically connected to the conductive shield. The second conductor is structured to be electrically connected to ground. A second sensor cooperates with the second conductor and is structured to sense signals associated with partial discharge activity. An electronic monitoring circuit receives the output of the second sensor. The electronic monitoring circuit is structured to provide on-line monitoring of a partial discharge occurring within the first medium voltage power conductor.

Abstract: 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 &agr; degrees, where &agr; is less than 180° and is 90° in the exemplary embodiment. A common fixed load contact is located angularly between, and spaced &agr; degrees from, both the fixed line and ground contacts so that the shaft is rotated only &agr; 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.

Abstract: 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 &agr; degrees, where &agr; is less than 180° and is 90° in the exemplary embodiment. A common fixed load contact is located angularly between, and spaced &agr; degrees from, both the fixed line and ground contacts so that the shaft is rotated only &agr; 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.