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  2. Heat detector - Wikipedia

    en.wikipedia.org/wiki/Heat_detector

    A residential heat detector. A heat detector is a fire alarm device designed to respond when the convected thermal energy of a fire increases the temperature of a heat sensitive element. The thermal mass and conductivity of the element regulate the rate flow of heat into the element. All heat detectors have this thermal lag. Heat detectors have ...

  3. Thermal conductivity detector - Wikipedia

    en.wikipedia.org/wiki/Thermal_conductivity_detector

    The thermal conductivity detector (TCD), also known as a katharometer, is a bulk property detector and a chemical specific detector commonly used in gas chromatography. [1] This detector senses changes in the thermal conductivity of the column eluent and compares it to a reference flow of carrier gas. Since most compounds have a thermal ...

  4. Fire alarm system - Wikipedia

    en.wikipedia.org/wiki/Fire_alarm_system

    Fire alarm systems are required in most commercial buildings. They may include smoke detectors, heat detectors, and manual fire alarm activation devices (pull stations). All components of a fire alarm system are connected to a fire alarm control panel. Fire alarm control panels are usually found in an electrical or panel room.

  5. Thermopile laser sensor - Wikipedia

    en.wikipedia.org/wiki/Thermopile_laser_sensor

    Figure 2: [8] Working principle of a thermal laser sensor (Adapted from figure 3 with permission) As shown in Fig 2, a thermopile laser sensor consists of several thermocouples connected in series with one junction type (hot junction at temperature T 1) being exposed to an absorption area and the other junction type (cold junction at temperature T 2) being exposed to a heat sink.

  6. Thermopile - Wikipedia

    en.wikipedia.org/wiki/Thermopile

    Picture of a heat flux sensor that utilizes a thermopile construction to directly measure heat flux. Model shown is the FluxTeq PHFS-01 heat flux sensor. Voltage output is passively induced from the thermopile proportional to the heat flux through the sensor or similarly the temperature difference across the thin-film substrate and number of ...

  7. Fire alarm notification appliance - Wikipedia

    en.wikipedia.org/wiki/Fire_alarm_notification...

    A Simplex-brand fire alarm bell. A fire alarm notification appliance is an active fire protection component of a fire alarm system.A notification appliance may use audible, visible, or other stimuli to alert the occupants of a fire or other emergency condition requiring action.

  8. NFPA 72 - Wikipedia

    en.wikipedia.org/wiki/NFPA_72

    The NFPA 72 "covers the application, installation, location, performance, inspection, testing, and maintenance of fire alarm systems, supervising station alarm systems, public emergency alarm reporting systems, fire warning equipment and emergency communications systems (ECS), and their components."

  9. Linear heat detection - Wikipedia

    en.wikipedia.org/wiki/Linear_Heat_Detection

    Linear heat detection (LHD) cable is essentially a two-core cable terminated by an end-of-line resistor (resistance varies with application). The two cores are separated by a polymer plastic, that is designed to melt at a specific temperature (commonly 68 °C for building applications [1]), and without which causes the two cores to short.