The working principle of linear fiber optic thermal fire detectors

Fiber optic temperature sensor, Intelligent monitoring system, Distributed fiber optic manufacturer in China

What is linear fiber optic

Linear fiber optic transmission technology is a technology that uses single-mode optical cables to restore broadband RF signals as undistorted as possible at the remote end. Its principle is to use high-performance optical transmitters and receivers to achieve long-distance transmission of broadband RF signals through analog optical cables. Unlike typical digital fiber optic cable transmission, signals in the fiber optic cable are transmitted in analog form.

Fiber optic thermal fire detector

In the analysis of fire temperature in various engineering systems, the temperature measurement method, scattered and discontinuous temperature measurement points, temperature measurement distance, temperature measurement accuracy, extraction of temperature signals, and positioning analysis of heating points are important links. Traditional temperature measurement devices have weaknesses such as live detection, low temperature accuracy, blurred positioning, low temperature response rate, short effective temperature measurement distance, and difficult construction. Develop a distributed linear fiber optic temperature measurement system that meets the requirements based on the actual temperature and fire monitoring signals of various engineering projects, combined with optical technology and electronic circuit technology. The more continuous the data collected by instruments for monitoring fire temperature in an effective area, the more realistic and accurate the actual signals collected. This requires a device with strong computing power and high-speed data acquisition and processing. Through long-term monitoring and analysis of temperature, many information about fire temperature can be obtained. Therefore, whether long-term, continuous, and accurate monitoring of fire temperature can be carried out largely determines the accuracy and timeliness of fire temperature warning and alarm.

Linear fiber optic temperature sensing fire detection system

A linear fiber optic temperature fire detector is a device used for real-time measurement of spatial temperature field distribution. Its main system equipment consists of temperature sensing optical cables, temperature calibration, data acquisition, data processing, and graphic display. Using the same optical fiber as the sensing and conducting medium for temperature information, the temperature field information of the fiber is measured using the temperature effect of the backward Raman scattering spectrum of the optical fiber, and the measurement points are located using the optical time-domain reflection (OTDR) technology of the optical fiber. Due to its inherent safety, corrosion resistance, high voltage resistance, electromagnetic interference resistance, and ability to quickly measure and locate multiple points, the device has a wide range of applications, such as temperature monitoring in petroleum engineering, power plants, mines, tunnels, and dams. It plays an important role in the safe operation of equipment and the safety of personnel and property.

The linear fiber optic temperature sensing fire detection system, as a new type of temperature measurement technology product in fire temperature measurement systems, can be widely used in many public fire protection systems. The fiber optic temperature sensing fire detection system can monitor the temperature hazards generated by fires in power systems such as cable tunnels, cable trays, and cable intermediate heads of enterprises. It can also be used for fire detection in coal conveyor belts and storage yards. The insulation and explosion-proof properties of fiber optic can be used to monitor the high-voltage switchgear, transformers, and other electrical equipment in coal mines in real time, eliminating potential accidents.
The linear fiber optic temperature sensing fire detection system, relying on its inherent safety and the timeliness of dynamic information, has gradually shown superiority in the safety fields of coal mine fire detection and early warning, significantly improving the level of mine production safety.

Working principle of linear fiber optic temperature sensing fire detection system

Based on the optical time-domain reflection (OTDR) of optical fibers and the temperature effect of Raman scattering in optical fibers. The detection fiber optic cable is laid in the space to be tested, and the fiber optic host emits a laser beam into the detection fiber optic cable and collects real-time Raman scattered light with on-site real-time temperature information scattered along the fiber optic cable. The fiber optic host analyzes and processes these optical signals to obtain temperature distribution information on the entire fiber optic cable. Compare the temperature information with the preset alarm parameter values. When the alarm conditions are met, the fiber optic host emits a fire alarm sound and light indication, and can output alarm information to the fire alarm controller.