Heat Detector
Intelligent, Sensitive and Industrial GradeSet to alarm when ambient temperatures reach a fixed point, typically indicating a fire, fixed-temperature heat detectors are a highly cost-effective solution for many property protection applications. If rapid response to fire is vital, rate-of-rise heat detectors are an ideal solution where rapid temperature increases would only be caused by a fire emergency.
Combination heat detectors provide both fixed and rate-of-rise detection. This enables the heat detector to communicate an alarm to the central control panel prior to reaching its fixed set point for high rates of rise, providing a timely response to both rapid and slow temperature increases.
The two types of heat detectors are spot and line type.
A spot type heat detector monitors temperature at a given point. These detectors vary with respect to the mechanisms used to detect heat.
Line type heat detectors are used in applications where it is not practical to use spot type detectors, such as on long industrial conveyors or cable trays. These detectors use heat-sensitive materials which affect the current flow through the electrical conductors.
- Restorable – returns to its ready state without any interaction from an outside source, once it has cooled below its set point.
- Non-Restorable – requires replacement of its element after actuation.
Rate-of-Rise Heat Detectors – operate on a rate-of-temperature change per unit of time basis. This type of heat detector contains a chamber with a calibrated vent. When the air in the chamber expands faster than it can escape from the vent, the increase in pressure causes the electrical contacts to close sending a signal to the fire alarm control unit. If the air in the chamber rises slowly and can escape from the vent, the electrical contacts do not close and there is no alarm.
Other types of spot detectors are:
- Rate-compensated heat detector
- Combination heat detector
- Pneumatic heat detector
