A system for determining when an electrical contact or other component reaches a predetermined temperature. In operation, a trace material is dispersed into a surrounding environment (e.g., head space within a compartment above insulating oil), where the trace material is detected. A barrier may be ruptured or broken by temperature-induced gas pressure, or pierced by a spring-loaded member that is located within the same section that contains the trace material, and devices may be provided for moving the trace material through the foil barrier as the barrier is ruptured. The barrier may be opened solely by internal gas pressure. According to another embodiment, improved fail-safe operation may be achieved by providing a spring-loaded member and configuring the barrier to be ruptured by the pressure of the detectable gas material before the barrier is ruptured by the spring-loaded member.

A system for determining when an electrical contact or other component reaches a predetermined temperature. In operation, a trace material is dispersed into a surrounding environment (e.g., head space within a compartment above insulating oil), where the trace material is detected. A barrier may be ruptured or broken by temperature-induced gas pressure, or pierced by a spring-loaded member that is located within the same section that contains the trace material, and devices may be provided for moving the trace material through the foil barrier as the barrier is ruptured. The barrier may be opened solely by internal gas pressure. According to another embodiment, improved fail-safe operation may be achieved by providing a spring-loaded member and configuring the barrier to be ruptured by the pressure of the detectable gas material before the barrier is ruptured by the spring-loaded member.

A system for determining when an electrical contact or other component reaches a predetermined temperature. In operation, a trace material is dispersed into a surrounding environment (e.g., head space within a compartment above insulating oil), where the trace material is detected. A barrier may be ruptured or broken by temperature-induced gas pressure, or pierced by a spring-loaded member that is located within the same section that contains the trace material, and devices may be provided for moving the trace material through the foil barrier as the barrier is ruptured. The barrier may be opened solely by internal gas pressure. According to another embodiment, improved fail-safe operation may be achieved by providing a spring-loaded member and configuring the barrier to be ruptured by the pressure of the detectable gas material before the barrier is ruptured by the spring-loaded member.

A system for determining when an electrical contact or other component reaches a predetermined temperature. In operation, a trace material is dispersed into a surrounding environment (e.g., head space within a compartment above insulating oil), where the trace material is detected. A barrier may be ruptured or broken by temperature-induced gas pressure, or pierced by a spring-loaded member that is located within the same section that contains the trace material, and devices may be provided for moving the trace material through the foil barrier as the barrier is ruptured. The barrier may be opened solely by internal gas pressure. According to another embodiment, improved fail-safe operation may be achieved by providing a spring-loaded member and configuring the barrier to be ruptured by the pressure of the detectable gas material before the barrier is ruptured by the spring-loaded member.

A system for determining when an electrical contact or other component reaches a predetermined temperature. In operation, a trace material is dispersed into a surrounding environment (e.g., head space within a compartment above insulating oil), where the trace material is detected. A barrier may be ruptured or broken by temperature-induced gas pressure, or pierced by a spring-loaded member that is located within the same section that contains the trace material, and devices may be provided for moving the trace material through the foil barrier as the barrier is ruptured. The barrier may be opened solely by internal gas pressure. According to another embodiment, improved fail-safe operation may be achieved by providing a spring-loaded member and configuring the barrier to be ruptured by the pressure of the detectable gas material before the barrier is ruptured by the spring-loaded member.

A bond inspection system may include a material that reacts to applied activation energy by creating a compression wave, the material positioned adjacent a surface of a structure having a bond to be inspected and shaped in a predetermined pattern, such that reaction of the material causes compression waves to travel through the surface and structure; a source of activation energy capable of directing the activation energy at the material; and a controller programmed to actuate the source of activation energy to direct the activation energy at discrete portions of the predetermined pattern of material in a predetermined sequence selected to create a plurality of the compression waves so that the compression waves reflect from an opposite side of the structure as a plurality of tension waves that combine at substantially the same time at a bondline of the structure to be inspected.

An exemplary embodiment provides matching media for perfect transmission of ultrasonic waves by easily implementing perfect transmission of ultrasonic waves at a boundary between different elastic media through a matching layer provided at the boundary between the different elastic media and proposes a matching layer having a single layer structure of a simple single pattern that is easily processed, thereby easily implementing effects such as miniaturization of the matching layer, reduction of manufacturing cost, and improvement of manufacturability. The matching medium for perfect transmission of ultrasonic waves according to an exemplary embodiment includes a matching layer that is provided with a single pattern under a perfect transmission condition at a boundary between an incident medium and a transmission medium to perfectly transmit the ultrasonic waves incident from the incident medium to the transmission medium, wherein the matching layer forms a single pattern by controlling a plurality of predetermined design variables.

The present heat-sensitive material is a heat-injectable and electrically insulating material, the heat-sensitive material including a polymer matrix, made of a thermoplastic polymer material or of a thermoplastic elastomer, a plasticizer, having a molar weight (M), and a filler in the form of particles, in particular carbon black. The molar weight (M) of the plasticizer is chosen according to a first predetermined temperature threshold (Ti), such that the heat-sensitive material is configured to release volatile species from the heated plasticizer and filler particles entrained by the plasticizer when the heat-sensitive material is subjected to a temperature higher than the first temperature threshold (Ti), said volatile species from the plasticizer and filler particles being detectable by a detection device.