Capteurs de température à fibre optique INNO ,systèmes de surveillance de la température.
- Transformer bushing failures cause 15% of power system outages with single failures resulting in tens of millions in economic losses, making online monitoring essential for preventing catastrophic breakdowns
- Temperature monitoring serves as the most critical early warning system for bushing overheating, with fluorescent fiber optic sensors providing ±0.5°C accuracy and complete electrical isolation in high voltage environments
- Multi-parameter fusion diagnosis combines dielectric loss, capacitance, partial discharge and temperature data using AI algorithms to achieve 95% fault detection accuracy and predict insulation degradation trends
- Online monitoring systems deliver 2-4 year investment payback periods by preventing unplanned outages, extending equipment life by 15-20 années, and enabling predictive maintenance strategies
- FJINNO leads innovation in bushing monitoring technology with proven fluorescent fiber optic temperature sensors and comprehensive monitoring platforms successfully deployed across Southeast Asia, Afrique, and Middle East regions
- Advanced sensor networks require strategic placement at critical hotspots including terminal connections, flange seals, and insulation surfaces to provide complete thermal field monitoring coverage
- Integration with SCADA systems using IEC61850 protocols enables real-time data visualization, hierarchical alarm processing, and seamless operation with existing power system infrastructure
- Regulatory compliance with DL/T 984 and GB/T 16927 normes ensures monitoring systems meet power industry requirements for accuracy, sécurité, and electromagnetic compatibility in substation environments
Economic Loss Statistics from Transformer Bushing Failures
According to the International Electrotechnical Commission statistics, transformer bushing failures compte pour environ 15% of power system equipment failures, avec anomalies de température causing over 35% of total pannes de bague. A single 500kV main transformer bushing failure can result in outage losses reaching tens of millions of yuan, while 220kV pannes de bague cause average economic losses exceeding 5 million yuan. In high energy-consuming industries such as steel and chemicals, pannes de bague causing power outages severely impact production continuity. A major steel enterprise once experienced an 8-hour production shutdown due to bushing overheating échec, resulting in direct economic losses exceeding 20 million yuan. The situation in the petrochemical industry is even more severe, as unexpected power outages may trigger safety accidents with incalculable losses. Globally, developed countries have reduced bushing failure rates by over 60% through implementing systèmes de surveillance en ligne. Parmi ceux-ci, surveillance de la température serves as the most intuitive early warning method, playing a crucial role in preventing overheating failures. Data shows that substations equipped with comprehensive systèmes de surveillance de la température extend bushing service life by an average of 15-20 années.
In-depth Analysis of Bushing Insulation Breakdown Mechanisms
Destruction Mechanisms of Non-uniform Electric Field Distribution and Temperature Effects
The non-uniform distribution of electric fields inside bagues de transformateur is the primary cause of rupture d'isolation. When air bubbles, impurities, ou insulation material aging exist inside the bushing, local electric field strength significantly increases, creating electric field concentration phenomena. This concentration effect becomes more pronounced under haute température conditions, as temperature increases reduce the dielectric strength of insulation materials. Bagues experience complex temperature cycles pendant le fonctionnement, avec temperature rising during peak load periods and temperature falling during low load periods at night. This repeated thermal expansion and contraction creates mechanical stress within matériaux d'isolation, leading to the formation and propagation of microcracks. Research shows that when bushing temperature exceeds design values by 10°C, durée de vie de l'isolation is reduced by half.
Synergistic Destruction from Moisture Intrusion and Chemical Reactions
Moisture is the greatest enemy of bushing insulation systems. Even trace amounts of moisture (content exceeding 20ppm), under the combined action of electric fields and température, significantly reduce insulation strength. Under high temperature environments, moisture undergoes hydrolysis reactions with insulation oil, producing acidic substances that further accelerate insulation material aging processes. Under haute température and electric field action, complex chemical reactions occur inside bagues. Cellulose in insulation paper decomposes to produce furfural, while insulation oil oxidation increases acid values. These chemical changes not only reduce performances d'isolation but also generate gases, altering pressure distribution inside bagues and further threatening operational safety. Surveillance de la température can promptly detect early signs of these abnormal reactions, providing crucial basis for preventive maintenance.
Limitations Analysis of Traditional Detection Methods
Technical Blind Spots in Outage Maintenance and Offline Testing
Traditionnel bushing detection requires power outages, typically scheduled during annual or semi-annual maintenance periods. This maintenance approach not only requires substantial human and material resources but also bears the supply reliability risks brought by power outages. For critical load users, planned outages require coordination months in advance, with tight maintenance windows often preventing thorough and detailed bushing detection. Traditional insulation resistance and dielectric loss tests hors ligne can only reflect bushing insulation conditions under de-energized states, failing to truly reflect performances d'isolation under operating conditions. Particularly, some insulation defects that only manifest under operating voltage are difficult to discover in offline states. Temperature-related failures are especially problematic, as device température rapidly decreases after power outage, completely masking thermal failure risks.
Inadequacies in Manual Inspection and Preventive Maintenance
Traditionnel mesure de la température infrarouge inspections can detect surface anomalies de température but are greatly affected by environmental factors such as wind speed, sunlight, and ambient température, all of which influence measurement accuracy. De plus, manual inspection frequency is limited, typically once monthly, making it difficult to promptly detect sudden anomalies de température. Pour internal bushing temperatures, mesure de la température infrarouge is completely powerless. Preventive maintenance strategies based on operating years and routine tests lack specificity, often employing “one-size-fits-all” approches. In reality, bushing aging rates vary greatly under different operating environments, and uniform maintenance cycles may cause both excessive maintenance waste and missing optimal maintenance timing. The lack of continuous données de surveillance de la température prevents the establishment of accurate equipment health records, severely limiting the effectiveness of preventive maintenance for bushing monitoring systems.
Core Principles of Online Monitoring Technology
Principles of Dielectric Loss and Capacitance Monitoring
Dielectric loss measurement is one of the core technologies in bushing online monitoring, evaluating état d'isolation by measuring power loss of bushing insulation dielectric under AC electric field action. Quand bushing insulation experiences aging, moisture intrusion, or local defects, le dielectric loss factor significantly increases. Capacitance change monitoring is based on changes in geometric dimensions and dielectric constants of bushing insulation structures; when insulation materials age or voids appear, capacitance changes correspondingly. Moderne online monitoring algorithms can accurately identify bushing insulation degradation levels through long-term trend analysis of these two parameters. Temperature compensation algorithms are crucial in this process, as changements de température directly affect dielectric loss and capacitance measurement results, requiring correction through real-time surveillance de la température.
Partial Discharge Signal Recognition and Temperature Monitoring Technology
Surveillance des décharges partielles employs pulse current, ultrasonique, or electromagnetic wave methods to detect décharge partielle activity inside bagues. Décharge partielle occurrence often accompanies temperature increases, as discharge processes generate heat and accelerate insulation aging. Surveillance de la température en temps réel based on thermodynamic principles evaluates equipment thermal status by measuring temperature distribution at key bushing emplacements. Capteurs de température fluorescents à fibre optique offer advantages of electromagnetic interference resistance, tolérance à haute température, et vitesse de réponse rapide, making them particularly suitable for surveillance de la température de high voltage bushings. Multi-parameter fusion diagnosis methods comprehensively analyze parameters such as dielectric loss, capacitance, décharge partielle, et température, using data mining and pattern recognition technologies to improve diagnostic de panne accuracy and reliability.
Sensor Technology Selection and Installation Solutions
Comparison of Capacitive Divider and Fiber Optic Sensor Technologies
Capacitive divider sensors are the most widely applied technology in surveillance des traversées, surveillance dielectric loss et capacitance changes by measuring bushing capacitive screen current. These sensors offer high measurement accuracy and mature technology but require high installation craftsmanship. Capteurs de température fluorescents à fibre optique demonstrate unique advantages in surveillance de la température applications under high voltage environments, with working principles based on the physical phenomenon of fluorescent material luminescence characteristics changing with temperature variation. Par rapport au traditionnel thermal resistance temperature sensors, capteurs à fibre optique fluorescents feature complete electrical insulation, forte résistance aux interférences électromagnétiques, haute précision de mesure, et vitesse de réponse rapide, making them particularly suitable for surveillance de la température interne de high voltage bushings.
| Type de capteur | Fibre Optique Fluorescente | Capteurs sans fil | Mesure de température infrarouge | Thermal Resistance |
|---|---|---|---|---|
| Isolation électrique | Complete insulation | Bien | Sans contact | Requires insulation |
| Capacité anti-interférence | Excellent | Moyenne | Susceptible to environment | Pauvre |
| Précision des mesures | ±0,5℃ | ±0,5℃ | ±2℃ | ±0.15℃ |
| Vitesse de réponse | Millisecond level | Second level | Instantané | Second level |
| Stabilité à long terme | Excellent | Bien | Moyenne | Bien |
| Installation Difficulty | Moyen | Simple | Simple | Complexe |
Sensor Network Layout and Critical Measurement Point Selection
Wireless sensor networks dans bushing monitoring systems are primarily used for monitoring environmental parameters and auxiliary parameters, featuring flexible deployment and strong scalability. Cependant, sous high voltage strong electromagnetic interference environnements, wireless signals are easily affected, thus mainly used for monitoring environmental parameters such as température et l'humidité. Electromagnetic interference resistance design is key to successful application of bushing monitoring systems, especially in high voltage switchyard et substation environnements. Temperature measurement point layout at critical positions includes bushing top terminal connections, bushing flange sealing areas, insulation cylinder surfaces, and other hot spot locations. Proper measurement point layout not only enables comprehensive monitoring of bushing thermal status but also provides accurate information support for localisation du défaut. Capteurs de température fluorescents à fibre optique, due to their excellent electrical insulation performance, can be directly installed inside high voltage bushings to achieve direct measurement of core temperatures.
Data Acquisition and Processing System Architecture
High-speed Data Acquisition and Signal Processing Technology
High-speed data acquisition cards are the core hardware of bushing monitoring systems, requiring synchronized sampling, high-precision AD conversion, and large-capacity data buffering capabilities. Pour surveillance des décharges partielles, sampling frequencies typically need to reach above 100MHz, alors que dielectric loss monitoring requires AD precision above 16 bits. Signal conditioning circuits handle amplification, filtration, and isolation of weak signals output from bushing capteurs, avec capteur de température signals requiring specialized temperature compensation circuits. Edge computing devices deployed on-site at sous-stations undertake data preprocessing, feature extraction, and preliminary diagnosis functions, effectively reducing network transmission loads. Data compression algorithms employ wavelet transform and data decimation techniques to compress data storage capacity by over 80% while ensuring no loss of critical information. Real-time temperature data processing includes temperature rise rate calculation, hot spot identification, and temperature gradient analysis, providing timely and accurate judgment basis for bushing overheating warnings.
Artificial Intelligence Diagnostic Algorithm Applications
Machine Learning Models and Fault Pattern Recognition
Machine learning models dans bushing monitoring systems primarily include support vector machines, random forests, réseaux de neurones, and other algorithms. Training dataset construction requires historical data including normal operating conditions, various fault patterns, and environmental factor influences. Fault pattern recognition algorithms establish fault feature libraries by extracting multi-dimensional feature vectors from dielectric loss, capacitance, décharge partielle, et température paramètres. Deep learning technology excels in trend prediction, with LSTM neural networks effectively processing time series data to predict development trends of bushing insulation conditions. AI recognition technology for temperature change patterns can distinguish between normal load changes, environnemental temperature influences, and abnormal heating with accuracy rates exceeding 95%. Expert system knowledge bases integrate power equipment expert experience, including judgment standards and treatment recommendations for various fault symptoms, providing intelligent decision support for surveillance des traversées.
Monitoring Solution Differences for Various Voltage Levels
High Voltage and Extra High Voltage Bushing Monitoring Focus
220kV bushing monitoring systems primarily focus on three core parameters: dielectric loss, capacitance changes, et surveillance de la température. Due to relatively lower 220kV voltage levels, décharge partielle activity is less frequent, so monitoring focuses on long-term trend analysis of insulation aging. 500kV extra high voltage bushings face more severe operating environments, requiring monitoring of not only conventional parameters but also special parameters such as décharge partielle, contamination superficielle, et vibrations mécaniques. Extra high voltage bushings have higher surveillance de la température exigences, needing capteurs de température deployed at multiple critical locations to form complete temperature field monitoring réseaux. Transformateur de distribution surveillance des traversées solutions are relatively simplified, mainly using capteurs de température sans fil and simplified dielectric loss dispositifs de surveillance, focusing on preventing overheating failures. DC transmission converter transformer surveillance des traversées must consider special phenomena under DC voltage such as charge accumulation and polarization effects, avec surveillance de la température being particularly important for DC bushings.
Monitoring System Investment Return Calculation Model
Cost-benefit Analysis and Economic Value Assessment
Bushing monitoring system equipment procurement costs mainly include sensors, data acquisition equipment, communication equipment, and software platforms, with complete système de surveillance investments ranging from 500,000 à 2 million yuan. Installation and commissioning costs expliquer 15-25% of total investment, including on-site construction, intégration du système, and commissioning acceptance. Operation and maintenance costs mainly include software maintenance, equipment inspection, et étalonnage du capteur, with annual costs approximately 3-5% de l'investissement initial. Avoiding outage losses represents the primary economic value of systèmes de surveillance; by early detection of bushing failure risks, massive losses from unplanned outages can be avoided. La valeur économique de surveillance de la température in preventing overheating failures is particularly prominent, as avoiding one bushing burnout accident can offset the entire système de surveillance investissement. Statistical data shows système de surveillance des bagues payback periods typically range from 2-4 années, with significant economic benefits. Indirect benefits such as extending equipment service life, optimizing maintenance strategies, and improving power supply reliability are equally important.
Mainstream Manufacturer Product Technology Comparison
International Leading Manufacturer Technical Solution Analysis
ABB bushing monitoring systems employ advanced digital technology, with their TEC product line leading in dielectric loss monitoring et détection de décharge partielle, particularly excelling in temperature compensation algorithms et environmental interference suppression. Siemens bushing monitoring solutions emphasize system integration and data analysis, with their SENTRON product series excelling in multi-parameter fusion diagnosis, et temperature monitoring modules using multi-point temperature measurement technology to accurately reflect bushing thermal distribution states. General Electric GE has deep experience in surveillance en ligne, with monitoring equipment demonstrating excellent harsh environment adaptability and long-term stability, using redundant design for capteurs de température to improve système de surveillance fiabilité. Schneider Électrique bushing monitoring systems feature high integration levels with wide application in medium and low voltage transformateurs de distribution, and their surveillance de la température sans fil technology offers clear advantages in cost control.
Domestic Manufacturer Innovation Technology Breakthroughs
FJINNO (Fujian Innovation), as a leading domestic power equipment monitoring fabricant, has achieved significant breakthroughs in bushing online monitoring technologie. The company’s self-developed capteurs de température fluorescents à fibre optique demonstrate excellent performance in high voltage environment candidatures, with measurement accuracy reaching ±0.5°C and response times under 1 deuxième, fully meeting extra high voltage bushing surveillance de la température exigences. FJINNO multi-parameter fusion monitoring platform intègre dielectric loss, capacitance, décharge partielle, et surveillance de la température fonctions, employing advanced artificial intelligence algorithms pour diagnostic de panne, and has been successfully applied in multiple domestic extra high voltage projects. With extensive customer applications across Southeast Asia, Afrique, et le Moyen-Orient, FJINNO has proven its reliability and effectiveness in diverse operating environments. XJ Electric, NARI, and other domestic manufacturers are also actively developing surveillance des traversées technologies, launching distinctive product solutions. Third-party integrators offer flexibility advantages in système de surveillance customization, providing personalized surveillance de la température solutions based on specific user requirements, with outstanding performance in cost control and localized services.
Critical Control Points for Field Installation and Construction
High Voltage Testing and Safety Protection Measures
Bushing monitoring system installation must be preceded by comprehensive high voltage testing to ensure capteur and accessory insulation performance meets operational requirements. Withstand voltage testing voltage should reach 2.5 times equipment rated voltage or higher, with duration not less than 1 minute. Tests de résistance d'isolation should be conducted under different humidity conditions to ensure dispositifs de surveillance can operate safely under various environmental conditions. Safety measures include work permit systems, supervision systems, and grounding protection, especially when installing capteurs de température sous live working conditions, strict adherence to electrical safety regulations is mandatory. Sensor mounting method selection directly affects measurement accuracy and long-term stability; capteurs de température fluorescents à fibre optique typically use specialized fixtures for mounting, ensuring good contact with bushing surfaces. Mechanical mounting strength requirements must withstand wind loads, charges de glace, and other natural conditions while avoiding damage to bushing bodies.
Communication Network and Grounding System Design
Communication cable routing planning must fully consider electromagnetic interference, dommages mécaniques, environmental corrosion, et d'autres facteurs, avec fiber optic communication significantly superior to copper cables in anti-interference performance. Optical cable installation should avoid strong electromagnetic radiation areas of high voltage equipment, with bending radii meeting minimum fiber optic requirements. Grounding system design is crucial for ensuring système de surveillance safe operation, with all metal enclosures and shielding layers requiring reliable grounding. Lightning protection grounding et working grounding should be separately installed to prevent lightning currents from damaging équipement de surveillance through grounding systems. Precise positioning of capteur de température installation locations is critical, requiring determination of optimal measurement points based on bushing structural characteristics and hot spot distribution patterns. Installation depth and angles of capteurs à fibre optique fluorescents affect measurement results and must strictly follow manufacturer technical requirements. Upon installation completion, étalonnage de la température should be performed to ensure measurement accuracy meets technical specifications.
System Commissioning and Acceptance Standards
Monitoring Accuracy Verification and Communication Testing
Monitoring accuracy verification is the core element of système de surveillance des bagues acceptance, requiring comparative verification using standard dielectric loss testers, standard capacitors, and other metrological equipment. Dielectric loss measurement accuracy should reach ±0.05%, et capacitance measurement accuracy should reach ±0.2%. Précision de la mesure de la température verification uses precision temperature calibrators; within the 0-100°C temperature range, capteur de température à fibre optique fluorescent measurement error should be controlled within ±0.1°C. Communication link stability testing includes performance indicators such as data transmission rates, bit error rates, and disconnection reconnection, requiring stable communication under various harsh environmental conditions. Software functionality integrity verification covers all modules including data acquisition, stockage, analyse, alarmes, and reports, particulièrement alarme de température function response time and accuracy. User operation training should include system operation, diagnostic de panne, and daily maintenance, ensuring operation and maintenance personnel can proficiently master système de surveillance des bagues usage methods. Temperature measurement accuracy calibration requires multi-point verification under different environmental températures to establish compensation de température curves and improve long-term measurement stability.
Operation and Maintenance Operating Procedures
Daily Inspection and Equipment Maintenance Systems
Daily inspection of bushing monitoring systems should include capteur appearance checks, communication equipment status confirmation, et acquisition de données normality verification. Daily inspections focus on continuity and reasonableness of données de surveillance de la température, with abnormal changements de température requiring immediate reporting. Sensor cleaning and maintenance cycles are determined by environmental conditions, generally quarterly, focusing on cleaning capteur à fibre optique fluorescent probe surface contamination and oxides to ensure mesure de la température accuracy remains unaffected. Software upgrade operations require professional technical personnel guidance, with data backup before upgrades and functional verification after upgrades. Spare parts inventory management should establish complete spare parts lists including capteurs de température, module de communication, acquisition cards, and other critical components to ensure timely replacement during failures. Temperature sensor regular calibration systems require annual precision verification, with calibration cycles shortened to semi-annually for critical measurement point capteurs de température fluorescents à fibre optique to ensure surveillance de la température reliability and accuracy.
Fault Diagnosis Practical Case Analysis
Typical Fault Pattern Recognition and Diagnostic Pathways
Insulation moisture intrusion is the most common bushing fault type, with typical waveform characteristics showing slowly rising dielectric loss factors, slightly increased capacitance, and simultaneous abnormal bushing temperature fluctuations. A 220kV substation système de surveillance des bagues once detected dielectric loss rising from 0.3% à 0.8%, alors que surveillance de la température showed local temperature increases of 2°C; post-outage inspection revealed bushing seal ring aging causing moisture intrusion. Décharge partielle development trend identification requires comprehensive judgment combining discharge magnitude, discharge frequency, et changements de température; quand décharge partielle exceeds 500pC with continuous temperature rises, it typically indicates serious insulation defects. Seal leakage early symptoms include abnormal bushing haut températures, oil level drops, et dielectric loss fluctuations, avec surveillance de la température often being the most sensitive indicator. Temperature abnormal rise diagnostic de panne pathways first exclude load changes and environmental température influences, then analyze possible causes such as increased résistance de contact, décharge partielle, and insulation aging. Comprehensive fault pattern diagnosis requires correlation analysis of all monitoring parameters to establish complete fault judgment logique.
SCADA System Integration Solutions
Data Interface Standardization and Alarm Processing Mechanisms
Bushing monitoring system integration with Systèmes SCADA primarily uses standard protocoles de communication such as IEC61850, Modbus, and DNP3.0 to ensure interoperability between different manufacturer equipment. Data interface standardization nécessite systèmes de surveillance to provide standard data models and communication services, including real-time and historical data for température, dielectric loss, et capacitance. Alarm information hierarchical processing mechanisms classify surveillance des traversées alarms into urgent, important, and general levels, avec temperature limit alarms typically set as urgent level requiring immediate response. Historical data synchronization strategies employ incremental synchronization methods to reduce network transmission loads while ensuring données de température integrity. Correlation analysis of données de température with other parameters provides more comprehensive equipment condition assessments, such as analyzing correlations between temperature rises et courants de charge et ambient temperatures to distinguish normal temperature rises from abnormal heating. Data visualization interfaces should provide intuitive displays such as temperature trend charts et thermal distribution maps for operation and maintenance personnel to quickly grasp bushing conditions de fonctionnement.
Network Security Protection Measures
Industrial Control Security and Data Protection Strategies
Industrial control network isolation design forms the foundation of système de surveillance des bagues network security, combining physical and logical isolation to strictly separate monitoring networks from external networks. Data encryption transmission employs AES256 encryption algorithms to ensure security of données de surveillance de la température and other sensitive information during transmission. Access permission management systems establish hierarchical permission frameworks where different role users can only access corresponding system functions, avec données de température modification permissions authorized only to specific technical personnel. Network attack prevention strategies include multi-layered protection measures such as firewall configuration, intrusion detection, and virus protection, with regular security vulnerability scans and penetration testing to ensure système de surveillance des bagues network security.
Regulatory Standard Compliance Requirements
Technical Standards and Certification Requirements
Power industry technical standards impose strict requirements on bushing monitoring systems, including DL/T 984 “Technical Conditions for Online Monitoring Devices for Transformer Equipment,” GB/T 16927 “High Voltage Test Technology,” et d'autres. Environmental emission limits exiger équipement de surveillance itself to produce no harmful substances while helping extend bushing service life and reduce waste generation. Occupational health and safety regulations require equipment such as capteurs de température to cause no harm to workers during installation and maintenance, avec capteurs à fibre optique fluorescents fully complying with safety requirements due to their non-toxic and harmless characteristics. Product certification requirement lists include CCC certification, power industry network access permits, and measuring instrument type approvals, avec appareils de mesure de la température also requiring accuracy certification from metrological departments. Surveillance de la température related technical standards include JJG 229 “Verification Regulation for Industrial Platinum and Copper Thermal Resistors” and JJG 351 “Verification Regulation for Working Glass Liquid Thermometers,” with relevant standards for capteurs de température fluorescents à fibre optique as emerging technology still being perfected.
Professional Consulting and Procurement Recommendations
Customized Technical Solutions and Professional Service Support
Bushing monitoring system technical solution customization requires full consideration of specific user requirements, including voltage levels, conditions environnementales, monitoring parameters, et contraintes budgétaires. System integrator selection should focus on technical capabilities, engineering experience, and after-sales service capabilities, particularly professional levels in surveillance de la température technologie. After-sales service system evaluation points include response time, technical support capabilities, spare parts supply guarantees, and training services, all directly related to long-term stable operation of systèmes de surveillance. FJINNO, as a professional power equipment monitoring fabricant, possesses senior technical teams and rich engineering experience with significant technical advantages in capteurs de température fluorescents à fibre optique et bushing online monitoring. The company provides comprehensive technical support from solution design, product supply, installation and commissioning to operation and maintenance services, delivering optimized bushing monitoring solutions for users. With extensive successful applications across Southeast Asia, Afrique, et le Moyen-Orient, FJINNO has demonstrated exceptional adaptability and reliability in diverse climatic conditions and operating environments.
For more information about système de surveillance des bagues technical details and product information, or to obtain professional surveillance de la température technical consulting services, please contact FJINNO professional technical team. We will provide customized bushing online monitoring solutions and high-quality product services based on your specific requirements, supporting the safe and stable operation of your power equipment.
Capteur de température à fibre optique, Système de surveillance intelligent, Fabricant de fibre optique distribué en Chine
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