Which components are used in the signaling system of fixed temperature detectors?

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Multiple Choice

Which components are used in the signaling system of fixed temperature detectors?

In fixed-temperature detectors, the signaling element is a sealed glass bulb filled with a volatile solvent. When the ambient temperature reaches the preset value, the solvent expands, increasing pressure inside the bulb and causing it to act—typically by rupturing or moving a mechanism that closes or opens electrical contacts to send the alarm signal. This setup provides a precise, repeatable response at a specific temperature. A flexible diaphragm is more typical in pressure-sensing devices, a bimetallic strip often underpins other types of thermal devices that rely on gradual bending rather than a fixed-point rupture, and a thermoelectric sensor is used in heat detectors that generate voltage changes (like thermocouples) rather than triggering a fixed-temperature signaling mechanism.

In fixed-temperature detectors, the signaling element is a sealed glass bulb filled with a volatile solvent. When the ambient temperature reaches the preset value, the solvent expands, increasing pressure inside the bulb and causing it to act—typically by rupturing or moving a mechanism that closes or opens electrical contacts to send the alarm signal. This setup provides a precise, repeatable response at a specific temperature.

A flexible diaphragm is more typical in pressure-sensing devices, a bimetallic strip often underpins other types of thermal devices that rely on gradual bending rather than a fixed-point rupture, and a thermoelectric sensor is used in heat detectors that generate voltage changes (like thermocouples) rather than triggering a fixed-temperature signaling mechanism.

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