Abstract: A temperature sensor has a heat-sensitive element contained within a chamber, the heat-sensitive element changing from a first configuration to a second configuration at a predetermined temperature, and a biased member biased towards the chamber. The biased member initially is prevented from entering the chamber when the heat-sensitive element is in the first configuration and enters the chamber when the heat-sensitive element is in the second configuration. In some aspects, the first configuration is solid and the second configuration is liquid and a selectively permeable element is provided to allow the heat-sensitive element to exit the chamber in the liquid configuration. An indicator can be provided that has a plurality of feet initially held in a retained configuration by the biased member until the biased member enters the chamber to release the feet for sliding motion of the indicator.

Abstract: A temperature sensor has a heat-sensitive element contained within a chamber, the heat-sensitive element changing from a first configuration to a second configuration at a predetermined temperature, and a biased member biased towards the chamber. The biased member initially is prevented from entering the chamber when the heat-sensitive element is in the first configuration and enters the chamber when the heat-sensitive element is in the second configuration. In some aspects, the first configuration is solid and the second configuration is liquid and a selectively permeable element is provided to allow the heat-sensitive element to exit the chamber in the liquid configuration. An indicator can be provided that has a plurality of feet initially held in a retained configuration by the biased member until the biased member enters the chamber to release the feet for sliding motion of the indicator.

Abstract: Apparatus and methods for non-invasively determining a temperature of a fluid inside a housing are provided. First and second temperature sensors are positioned so that there is a temperature differential between the first and second temperature sensors. A difference between the temperature of the first and second temperature sensors can be used to estimate the temperature of the fluid inside the housing and/or a zero heat flow methodology can be used to determine the temperature of the fluid inside the housing.

Abstract: A fault detector for detecting the occurrence of a rapid pressure rise within electrical equipment. The fault detector has a chamber having an interior, a diaphragm in sealing engagement with the chamber and an aperture providing fluid communication between the interior of the chamber and the external environment of the chamber.

Abstract: An integrated fault monitoring apparatus for electrical devices has an internal fault detector for detecting transient pressure surges within the electrical device, a pressure relief valve for allowing release of pressure during normal operating conditions of the electrical device, a temperature indicator for indicating that an operating temperature of the electrical device has gone above a predetermined threshold, and/or a sudden pressure relief device for allowing air to escape from the electrical device in the event of a sudden and significant increase in pressure within the electrical device. Methods of using the apparatus are provided.

Abstract: A temperature sensor has a heat-sensitive element contained within a chamber, the heat-sensitive element changing from a first configuration to a second configuration at a predetermined temperature, and a biased member biased towards the chamber. The biased member initially is prevented from entering the chamber when the heat-sensitive element is in the first configuration and enters the chamber when the heat-sensitive element is in the second configuration. In some aspects, the first configuration is solid and the second configuration is liquid and a selectively permeable element is provided to allow the heat-sensitive element to exit the chamber in the liquid configuration. An indicator can be provided that has a plurality of feet initially held in a retained configuration by the biased member until the biased member enters the chamber to release the feet for sliding motion of the indicator.

Abstract: An integrated fault monitoring apparatus for electrical devices has an internal fault detector for detecting transient pressure surges within the electrical device, a pressure relief valve for allowing release of pressure during normal operating conditions of the electrical device, a temperature indicator for indicating that an operating temperature of the electrical device has gone above a predetermined threshold, and/or a sudden pressure relief device for allowing air to escape from the electrical device in the event of a sudden and significant increase in pressure within the electrical device. Methods of using the apparatus are provided.

Abstract: An integrated fault monitoring apparatus for electrical devices has an internal fault detector for detecting transient pressure surges within the electrical device, a pressure relief valve for allowing release of pressure during normal operating conditions of the electrical device, a temperature indicator for indicating that an operating temperature of the electrical device has gone above a predetermined threshold, and/or a sudden pressure relief device for allowing air to escape from the electrical device in the event of a sudden and significant increase in pressure within the electrical device. Methods of using the apparatus are provided.

Abstract: An integrated fault monitoring apparatus for electrical devices has an internal fault detector for detecting transient pressure surges within the electrical device, a pressure relief valve for allowing release of pressure during normal operating conditions of the electrical device, a temperature indicator for indicating that an operating temperature of the electrical device has gone above a predetermined threshold, and/or a sudden pressure relief device for allowing air to escape from the electrical device in the event of a sudden and significant increase in pressure within the electrical device. Methods of using the apparatus are provided.

Abstract: A fault indicator for indicating the occurrence of a rapid pressure surge within a housing of an electrical device has: a barrel capable of being mounted in an aperture of the housing; an actuating mechanism having a chamber with at least one orifice communicating between interior and exterior surfaces of the chamber within the housing and an actuating member movable in response to a pressure differential between the interior and exterior surfaces of the chamber; a plunger within the bore of the barrel biased outwardly in the barrel and normally retained in an armed position by the actuating member; and a radial seal disposed between the plunger and the barrel. When the pressure differential exceeds a positive threshold value, the actuating member is moved and thereby permits the plunger to move outwardly into a triggered position. The radial seal may be a dual-lip seal.

Abstract: A fault indicator for indicating the occurrence of a rapid pressure surge within a housing of an electrical device has: a barrel capable of being mounted in an aperture of the housing; an actuating mechanism having a chamber with at least one orifice communicating between interior and exterior surfaces of the chamber within the housing and an actuating member movable in response to a pressure differential between the interior and exterior surfaces of the chamber; a plunger within the bore of the barrel biased outwardly in the barrel and normally retained in an armed position by the actuating member; and a radial seal disposed between the plunger and the barrel. When the pressure differential exceeds a positive threshold value, the actuating member is moved and thereby permits the plunger to move outwardly into a triggered position. The radial seal may be a dual-lip seal.