Abstract: A method for detecting a high pressure condition within a high voltage vacuum device includes detecting the position of a movable structure such as a bellows. The position at high pressures can be detected optically by the interruption of a light beam reflected by a hemispherically shaped reflector. The hemispherical reflector allows the source light fiber to oriented parallel to the detection light fiber, providing a more compact and efficient fiber routing.

Abstract: A method and apparatus for detecting a high pressure condition within an interrupter includes introducing high intensity ultrasonic sound into the outer wall of a vacuum interrupter through a sonic wave guide, then listening for the reflected and retransmitted response signals. The characteristics of the response signals are utilized to determine the pressure within the interrupter, and to determine when an unwanted high pressure condition exists.

Abstract: A method for detecting a high pressure condition within a high voltage vacuum device includes detecting the position of a movable structure such as a bellows. The position at high pressures can be detected optically by the interruption of a light beam reflected by a hemispherically shaped reflector. The hemispherical reflector allows the source light fiber to oriented parallel to the detection light fiber, providing a more compact and efficient fiber routing.

Abstract: A vacuum-type electrical switching apparatus (10) for high voltage electrical power. A vacuum pressure condition in a vacuum pressure space (21) surrounding electrical contact points (18) is monitored and movement of the contact points between open and closed positions is automatically prevented when the pressure exceeds a predetermined threshold in order to avoid destructive arcing between the points. A sensor (32) provides a vacuum signal (34) responsive to the vacuum pressure condition. A controller (36) automatically inhibits movements of the contact points when the vacuum signal indicates that the vacuum has degraded. A contactor (38) may be placed in series with power supply (28) and a solenoid (24) used to move the contact points, with the contactor being automatically opened by the controller in response to the degraded vacuum condition.

Abstract: A method for detecting a high pressure condition within an interrupter includes measuring the intensity of light emitted from an arc created by contacts within the interrupter, comparing the measured intensity with a predetermined value, and providing an indication when the measured intensity exceeds the predetermined value.