A device that responds to heat by a bimetallic element is categorized as which detector type?

A device that responds to heat by a bimetallic element is categorized as which detector type?

• A. Rate-of-rise detector
• B. Fixed-temperature detector
• C. Spot-type detector
• D. Ionization detector

Answer: (C)

A detector that uses a bimetallic element to respond to heat is a heat detector, and when described as a spot-type device, it’s a point detector installed at a fixed location to monitor a small area. The bimetallic strip bends as it heats, triggering the circuit when the local temperature crosses a set threshold, which is a common mechanism for fixed-temperature heat detectors. This type is typically deployed as a spot-type detector because the sensing occurs at a particular point rather than along a line or over a large area. The other options describe different detection approaches (rate-of-rise focuses on rapid temperature increase, ionization is for smoke) or installation styles, not the point-detection emphasis implied here.

A detector that uses a bimetallic element to respond to heat is a heat detector, and when described as a spot-type device, it’s a point detector installed at a fixed location to monitor a small area. The bimetallic strip bends as it heats, triggering the circuit when the local temperature crosses a set threshold, which is a common mechanism for fixed-temperature heat detectors. This type is typically deployed as a spot-type detector because the sensing occurs at a particular point rather than along a line or over a large area. The other options describe different detection approaches (rate-of-rise focuses on rapid temperature increase, ionization is for smoke) or installation styles, not the point-detection emphasis implied here.