Abstract: To provide an evaluation of the remaining life (level of insulation degradation) of wire in an installation, a kit-based approach avoids the need for technical personnel to visit a customer location. The kit includes equipment and instructions for selecting specimens for removal, capturing pre-removal information, removing the specimens, and sending the specimens for evaluation. A round form padded with protective material simplifies packing of the specimens while avoiding customer damage to the specimens. Accelerated aging testing and comparison between results for specimens from zones particularly susceptible to aging and one or more reference specimens permits an evaluation of remaining wire life.

Abstract: A part of a wire is tested, in situ, for degradation. The part of the wire is optionally enclosed in a jacket. A conductive medium is disposed on the wire. A test unit has a test elements in contact with the conductor of the wire and with the conductive medium. An attempt is made to induce a current along a path from the test unit, through the conductor, through the conductive medium, and back to the test unit. If a current is induced, degradation is detected. The test unit receives a cable of wires, and a selector switch of the test unit electrically couples a voltage source to selected elements of the cable in turn. Wires are tested in situ in an aircraft or other restrictive location.

Abstract: A current-responsive, resettable, violence-free low fault range vacuum-type switch interrupter is disclosed which is especially designed for series connection with a high fault range current limiting fuse (CLF) to achieve an improved, full range circuit protecting device adapted for use in padmounted, oil filled switch gear apparatus or the like. The resettable switch includes a spring-loaded, over center toggle motive assembly along with a current-responsive, temperature sensitive, bimetallic U-shaped latching element; in the event of a fault, the element deforms and releases the motive assembly to quickly open the vacuum contacts without the violence or oil contamination associated with fuse links. Manual opening of the contacts, and resetting thereof after either manual or fault-induced contact opening, is achieved through appropriate manipulation of an external, trip-free operating handle.

Abstract: A high dielectric strength seal between the encapsulant and the outwardly projecting actuating arm of an externally operable encapsulated vacuum switch includes a fluid-receiving sealed cavity surrounding the actuating arm between the latter and the encapsulant. An externally accessible valve permits charging of the cavity with a dielectric fluid subsequent to encapsulation of the switch to insure displacement of air from the interface between the encapsulant and actuating arm, thereby greatly reducing the likelihood of corona formation and dielectric breakdown of the seal. Additionally, the dielectric fluid may be pressurized through the valve to preclude infusion of conductive contaminants into the cavity. In preferred forms, an accumulator is in fluid communication with the cavity to permit thermal expansion and contraction of the dielectric fluid without undesired leakage or cavitation of the liquid.