Abstract: Techniques for detecting vacuum loss in a vacuum interrupter are disclosed. For example, a sensing system of a vacuum interrupter includes a sensor including a material that oxidizes in the presence of air and is at least partially positioned in an evacuated space of a vacuum interrupter, the sensor being configured to produce an indication of impedance of the material; and a control system coupled to the sensor, the control system including an electronic processor and an electronic storage that stores instructions that, when executed, cause the electronic processor to access an indication of impedance produced by the sensor, determine a measure of impedance of the material of the sensor based on the accessed indication of impedance, and determine a condition of the evacuated space based on the determined measure of impedance.

Abstract: A current-limiting fuse for use at voltages between 23 kilovolts (kV) and 38 kV includes a body including a sidewall that at least partially defines an interior space; a fuse element in the interior space of the body, the fuse element wrapped around a non-conductive core and connected to first and second electrically conductive plates; and a non-bound particulate material in the interior space of the body, the non-bound particulate material including a plurality of pieces of the material with voids between at least some of the pieces. A fuse holder for use at voltages between 23 kV and 38 kV includes a housing for insertion in a sidewall of a transformer. The housing includes an exterior surface that defines an interior region. A fuse assembly is received in the interior region of the housing, the fuse assembly being configured to be replaced without opening the tank of the transformer.

Abstract: A current-limiting fuse for use at voltages between 23 kilovolts (kV) and 38 kV includes a body including a sidewall that at least partially defines an interior space; a fuse element in the interior space of the body, the fuse element wrapped around a non-conductive core and connected to first and second electrically conductive plates; and a non-bound particulate material in the interior space of the body, the non-bound particulate material including a plurality of pieces of the material with voids between at least some of the pieces. A fuse holder for use at voltages between 23 kV and 38 kV includes a housing for insertion in a sidewall of a transformer. The housing includes an exterior surface that defines an interior region. A fuse assembly is received in the interior region of the housing, the fuse assembly being configured to be replaced without opening the tank of the transformer.

Abstract: Techniques for detecting vacuum loss in a vacuum interrupter are disclosed. For example, a sensing system of a vacuum interrupter includes a sensor including a material that oxidizes in the presence of air and is at least partially positioned in an evacuated space of a vacuum interrupter, the sensor being configured to produce an indication of impedance of the material; and a control system coupled to the sensor, the control system including an electronic processor and an electronic storage that stores instructions that, when executed, cause the electronic processor to access an indication of impedance produced by the sensor, determine a measure of impedance of the material of the sensor based on the accessed indication of impedance, and determine a condition of the evacuated space based on the determined measure of impedance.

Abstract: A dielectric fluid that provides improved resistance to device failure in capacitors comprising combinations of certain anthraquinone compounds and scavengers. Capacitors including the dielectric fluid can have a higher discharge inception voltage and can have increased failure threshold voltages in comparison to capacitors made without the combination. Therefore, these capacitors are more resistant to failures.