The real-time monitoring device for cable head temperature can mainly use fluorescent fiber optic temperature measurement devices. FJINNO is a manufacturer of cable head temperature warning and temperature measurement, providing an online monitoring system solution for cable head temperature.
Why do cable heads need temperature monitoring
As an essential part of power distribution facilities, the insulation reliability of cable heads plays a crucial role in the safe operation of the power distribution system. Usually, temperature plays a decisive role in the aging degree of the insulation layer of cable heads. If the temperature exceeds the safe range and lasts for a long time, it will accelerate the aging and detachment of the insulation layer of cable heads. If the cable breaks, grounding faults occur, and the cable connection is not tight, it will cause the temperature of the cable to rise. When the temperature rises, the insulation performance of the cable head will decrease or completely lose its insulation performance, which will have great safety hazards, such as cable short circuits, explosion and fire causing significant property damage and even endangering human life safety. Therefore, it is necessary to monitor the temperature of cable heads, and it is important to eliminate fault hazards in advance.
The faults and power outages of cable lines are mainly divided into external force damage faults and defect type faults. External force damage mainly occurs in the cable body, such as breaking and excavating, stealing cables, and defect type faults mainly occur at the cable terminals. The main cause of defect type faults is the breakdown of cable heads in the ring main unit and cable branch box, resulting in phase to phase short circuits. Once the cable terminal defect in the ring main cabinet or cable branch box develops into a breakdown fault, it often causes the entire space to be covered with dust and black ash. In severe cases, it can cause deformation of space components due to air pressure impact. After the cable head malfunctions and breaks down, emergency repairs often require cleaning, box deformation correction, or even overall replacement of the ring main unit or cable branch box, which greatly increases the time consumption compared to actively powering off to handle defects.
Why does the cable terminal in the ring main cabinet or cable branch box heat up
(1) Thermal breakdown: Due to the presence of insulation medium loss, solid insulation medium will gradually heat up in the electric field. The increase in temperature will lead to a decrease in the resistance of the solid insulation medium, a further increase in current, and an increase in loss and heating. While the insulation medium continuously heats up, there is also a process of continuously dissipating heat outward through electrodes or other media. When heating is faster than heat dissipation, the temperature of the medium will continue to rise, causing the insulation medium to decompose and carbonize, ultimately leading to breakdown.
(2) Heating defects: Due to issues with construction technology or material quality, conductor parts such as cable cores and joint terminals are often prone to heating defects. The combined effect of conductor heating and cable thermal breakdown mechanism ultimately leads to cable insulation breakdown, resulting in faults. At present, there is no effective device or means to detect the heat condition of cables in cable branch boxes and ring main cabinets.
FJINNO has independently developed a dedicated cable head temperature online monitoring system, specifically designed to eliminate overheating accidents caused by unreliable cable installation, which can avoid hidden accidents and greatly improve the reliability of the power supply system. The data acquisition terminal can transmit the temperature data collected by the temperature probe to the control room or relevant maintenance personnel of the power supply bureau. If there is any abnormal temperature phenomenon, the fault should be promptly eliminated to avoid serious consequences;
Characteristics of Fluorescent Fiber Optic Temperature Measurement System for Cable Head
1. The cable head fiber optic temperature measurement system fully considers the dispersion of the monitoring area and the complexity of the working environment, such as strong electromagnetic interference, temperature changes, etc., and takes corresponding measures. It has usability and reliability in special environments, and continuous real-time temperature measurement display and upload, as well as historical records.
2. The cable head fluorescent fiber optic temperature measurement host is equipped with remote monitoring function. By using the network on a remote monitoring computer, it is possible to understand the situation of each detection point on site, which is very convenient for leaders to timely understand the situation on site and is conducive to their decision-making and command.
3. The fiber optic temperature measurement device for cable joints has control functions. Capable of transmitting information downwards, issuing operation and control instructions, and operating some controllable devices to improve automation level.
4. The cable head fiber optic temperature monitor has a high degree of automation and can achieve temperature monitoring of the entire factory’s cables on the monitoring host, including online temperature monitoring of power equipment and temperature monitoring of cable channels.
5. The cable temperature control system has high alarm accuracy and anti false alarm function. By using anti false alarm algorithms, the occurrence of false alarms can be effectively avoided, and faults in both the system and the detector itself can be monitored simultaneously. Equipped with sound and light alarms, the monitoring host can record and print events, and has historical data queries for easy post analysis.
6. Fluorescent fiber optic temperature sensors can be integrated with temperature measurement cable bus interfaces, with advantages such as small size and strong anti-interference ability.
7. The fluorescence fiber optic temperature measurement system has good compatibility. This system can connect and integrate temperature measurement systems, temperature sensing systems, and other power equipment, greatly saving system investment.