Anbak Systems

Case Studies

Optical Fiber based Linear Heat Detection System installed in Abu Dhabi Corniche Tunnels

Anbak has proudly installed the optical fiber based linear heat detection system designed & manufactured by

in Baynoonah Tunnel & Corniche tunnel of Abu Dhabi. A two core special optical fiber cable is installed under the tunnel ceiling, along the entire length of the tunnel. This cable acts as the temperature sensor.

Protectowire's distributed temperature measurement is based on the proven Raman-Optical Time-Domain-Reflectometry (OTDR) technique. An optical laser pulse propagating through the sensor fiber gets scattered light back to the transmitting end, where it is analyzed using a patented code sequence measurement concept. The backscattered light is spread across a range of wavelengths. Some of these wavelengths are affected by temperature changes while others are immune. The intensity of the Raman signals is a measure of the temperature along the fiber. By very accurately measuring the difference in the signal intensity of the backscattered light an accurate temperature measurement can be made.

The local position of an alarm temperature is determined by measuring the arrival time of the returning light pulse similar to a radar echo showing the distance of a car or plane. This enables the FiberSystem PTS Controller to provide an exact location of a fire or hot spot anywhere along the sensor's length. Temperatures are recorded as a continuous profile. The system is also capable of providing graphical representation of the fire size and direction of fire spread based upon the length of sensor in alarm.