The environment of subway tunnel is complex, which has the characteristics of long tunnel distance and many detection points. It is difficult to warn the fire caused by power cable, mechanical and electrical equipment and other external causes. In the optical fiber temperature measurement system, the optical fiber is not only the transmission medium but also the sensing medium. At the same time, because the optical fiber is cheap and can be laid for a long distance, for example, the optical fiber is laid along the distribution cable, mechanical and electrical equipment and other places prone to fire in the tunnel. The optical fiber temperature measurement system which can describe the temperature field in the underground space is used to continuously monitor and accurately locate the temperature parameters according to the space The specific situation of temperature field change, to determine whether there is a fire hazard and timely forecast, to provide an advanced, reliable, economic and practical fire early warning and detection system for the safe operation of the subway, to realize the online monitoring and information management of the whole line of stations, and comprehensively improve the operation safety, with significant social comprehensive benefits

Advantages of the system:

    Distributed optical fiber temperature measurement system is a kind of sensor system used to measure the distribution of space temperature field in real time. It uses the same optical fiber as the sensing and conducting medium of temperature information, uses the temperature effect of Raman scattering spectrum to measure the temperature field information of optical fiber, and uses OTDR technology to locate the measuring point

   As a sensor, optical fiber body has strong anti electromagnetic interference ability, small size, light weight, simple structure, strong multiplexing ability, long transmission distance, corrosion resistance, high sensitivity, etc

Technical features:

1、Zone measurement: the measurement area can be arbitrarily divided in length, and some areas can be locally monitored and alarmed.

2、Alarm function: with constant temperature alarm, temperature rise alarm, fiber break alarm, device abnormal alarm and other alarm functions.

3、Alarm and zone setting: the setting of fire zone, constant temperature alarm, temperature rise alarm and the configuration of alarm output are all set by software, flexible and convenient.

Performance index:

1、Measuring distance  2/4/6/8/12/16/20/30/40KM

2、Working voltage  AC220V,50HZ or DC24V

3、Temperature measurement range  -70-300℃

4、 Temperature measurement accuracy  ±0.5℃

5、Corresponding time  ≤6S/Channel

6、Spatial resolution 1M

7、Communication interface  100MEthernet、RS2S2、RS485