Which is a good distributed fiber optic temperature sensor depends on the specific requirements of your project, whether the tested object is a pipeline or a comprehensive pipe gallery, or a fire equipment cable, and how far it is.
Function of distributed temperature sensing fiber optic system
1. Temperature monitoring of cables and cable joints; Real time temperature monitoring and abnormal alarm dynamic current carrying capacity monitoring of high-voltage cables and their joints through a distributed fiber optic temperature measurement system; Calculate the temperature of the cable core through dynamic current carrying capacity mathematical cross-section, further calculate the dynamic current carrying capacity, and horizontally simulate various operating states;
2. Temperature monitoring of cable interlayer, switchgear, etc; Temperature monitoring and fire warning of key areas such as cable interlayers and switchgear are carried out through distributed fiber optic temperature measurement systems and fluorescent point temperature measurement systems;
3. Monitoring of protective layer grounding cables; By using high-precision current transformers to monitor the leakage current of the grounding wire, limited monitoring and abnormal alarm of the protective layer grounding current can be achieved;
4. Partial discharge monitoring; By installing high-frequency current sensors on the grounding wire of cable joints, partial discharge information is obtained and insulation defects of cables and joints are analyzed, providing criteria for evaluating the aging degree of other insulation levels;
5. Data analysis: storing, querying, and analyzing historical data;
6. Remote access: The system can connect to industrial Ethernet and transmit data to various levels of management departments in the mining area, achieving remote access.
Characteristics of China’s Distributed Fiber Optic Temperature Sensing System
1. Fastness:
The system has a very high temperature measurement and positioning speed. In order to improve measurement time, high-speed data filtering technology was adopted to solve the optimization problem of massive digital filtering;
The laser emission device inside the system host emits tens of thousands of light pulses per second and outputs the average sampling temperature to the display system, basically eliminating errors.
2. Distribution characteristics:
The distributed fiber optic sensing system is a distributed fiber optic temperature measurement system that can provide continuous dynamic monitoring of temperature changes at points every 0.5 meters within a range of more than ten kilometers, and can set temperature alarm values at any level.
3. Progressiveness:
This system is currently the product with the highest performance indicators, strongest functionality, highest reliability, and most advanced technology in the world. The optical components used are imported devices produced through nanotechnology.
4. Accuracy:
The sampling interval of the system is 0.5m, with a temperature resolution of 0.1 ℃ and a temperature accuracy of ± 1 ℃; The positioning accuracy reaches ± 0.5m.
5. Flexibility:
The time for uploading alarm signals from any point within the monitoring range to the comprehensive monitoring system shall not exceed 2 seconds;
The host of this system can provide relay interfaces (passive dry contacts) for alarm on the fire alarm controller, and can provide a set of dry contact alarm signals according to the interval;
The monitoring system provides a continuous dynamic monitoring signal, and the system can set multi-level temperature point alarms. The system supports multi-level alarms, such as 40 ℃ pre alarm, 50 ℃ measures, etc., and can set temperature parameters for alarm points according to different environments;
To avoid false alarms, the temperature rise rate can be set in the alarm setting to monitor the characteristics of high temperature change rate before accidents occur. When the temperature rise rate is detected to be greater than this value, an alarm signal will be issued and corresponding signal output will be provided;
Multiple alarm conditions, as long as one is met, the system will immediately generate an alarm. The sampling interval can be adjusted according to on-site requirements, with a minimum sampling interval of 0.5 meters;
The alarm control area is programmable and can be flexibly designed according to user requirements. Each system can set up no less than 300 different alarm control areas per kilometer in response to environmental changes. For the on-site installation of power cables, the system can set two cable wells as a partition. When an abnormal situation occurs in a certain partition, FJINNO’s distributed fiber optic temperature measurement system will automatically package and upload the alarm information of this partition (such as location, alarm type, temperature value, etc.) to the centralized monitoring system.
6. Compatibility:
The host of the distributed fiber optic sensing system is an open communication protocol, which provides a communication interface to connect with the workstation. All information such as temperature curve, alarm position, and alarm temperature are displayed in graphic and textual form on the central control center workstation;
The system can be connected to other control devices such as PC and fire alarm systems through output forms such as RS232, RS485, built-in relays, RJ45, or other industrial protocols, to perform sound and light alarms, and the signal output is accurate and complete;
The distributed fiber optic sensing system can output signals in segments and levels according to different alarm zones to meet the needs of different control panels;
7. Security:
System software authorization management, secure and reliable;
Users can update the system for future upgrades and maintenance;
The distributed fiber optic sensing system has a security recording function, which can store all historical data since the system’s operation and can be downloaded using a portable computer;
If the fiber optic cable is damaged, the system can locate the damaged point, have self diagnosis function, and fuse it through the fiber optic fusion splicer, which is very important for effective online monitoring implementation;