The DC side of the photovoltaic system carries high-voltage DC voltage for a long time. The insulation layer inside the component cables, combiner boxes, and inverters is susceptible to insulation degradation due to moisture, aging, and external damage, which can cause leakage, grounding short circuits, inverter burnout, and even fire safety accidents. According to GB/T 35694 Photovoltaic Power Station Safety Regulations and IEC 62446 International Photovoltaic Safety Standards, special testing of system insulation resistance must be completed for grid connection acceptance and quarterly operation and maintenance inspections of photovoltaic power stations. Traditional universal megohmmeters are not optimized for photovoltaic active DC systems, and are susceptible to interference from component spontaneous currents during measurement, resulting in numerical distortion and inability to accurately determine insulation faults; Large scale photovoltaic insulation equipment is bulky and not suitable for on-site testing of distributed small-scale power stations on rooftops and households. Jiangsu Jingwei is deeply involved in the field of photovoltaic electrical safety testing and has launched the JW-J25 portable photovoltaic specific insulation resistance tester. It is equipped with photovoltaic specific anti-interference measurement algorithm, multi level high-voltage output, lightweight body design, and one-stop solution for insulation safety testing needs of photovoltaic modules, strings, DC cables, and combiner boxes. Leakage current test
JW-J25 is specially developed for photovoltaic active DC systems, with built-in photovoltaic current suppression compensation circuit, effectively offsetting the reverse current interference generated by component light generation. Even in outdoor light environments during the day, it can accurately measure insulation resistance without waiting for night power outage operations, greatly improving operation and maintenance inspection efficiency. It is different from ordinary megohmmeters that can only measure without the limitation of light environment. The equipment is equipped with four standard DC test voltages of 250V, 500V, 1000V, and 1500V, fully covering the measurement requirements of household low-voltage photovoltaic to 1500V high-voltage string centralized photovoltaic full voltage level system. The insulation resistance measurement range is 0.01M Ω to 20G Ω, and the ultra-high resolution accurately captures weak leakage hazards. The equipment automatically calculates the polarization index PI and absorption ratio DAR, two major safety judgment indicators, and the values are displayed in real time. The operation and maintenance personnel can directly compare the industry safety standards to quickly judge whether the insulation is qualified or not, without manual conversion calculation, reducing the technical threshold for operation.
The whole machine adopts a portable handheld integrated design, with a compact size and a weight of only 3.3kg. It is equipped with insulation extended test probes and high-voltage protection test clips. A single person can complete the insulation measurement of roof components, inverter DC terminals, and outdoor combiner boxes by hand. The storage protective box is easy to carry with the vehicle and is suitable for mobile operation scenarios such as household photovoltaic on-site inspection, mountain photovoltaic zoning inspection, and regular safety inspection of industrial and commercial rooftop photovoltaics. The equipment is equipped with an intelligent safety protection system, which monitors the circuit voltage in real-time at the high-voltage output end, automatically discharges after measurement, and eliminates the risk of residual high-voltage electric shock; Built in sound and light alarm mechanism, when the insulation resistance is below the national standard safety threshold, the screen will display a red warning and continuously beep to remind the operation and maintenance personnel to investigate grounding and leakage faults in a timely manner, ensuring the dual safety of the testing personnel and power station equipment. The equipment circuit has undergone multiple EMC electromagnetic compatibility optimizations, and the measurement values of outdoor power plant frequency converters and inverters are stable without jumping in the electromagnetic interference environment. The anti-interference ability far exceeds that of general insulation measuring instruments.
The adaptability to complex outdoor working conditions has been comprehensively optimized. The JW-J25 host adopts an IP54 dustproof and waterproof industrial protective shell, which can withstand outdoor rainwater, sand and dust, and temperature difference impacts. It can work stably in a wide temperature range of -20 ℃ to 60 ℃, and can be used for a long time in northwest desert, south high humidity and rainy, and coastal salt spray environments. Equipped with a large capacity lithium battery, it can continuously complete 500 high-voltage insulation tests when fully charged. It can be inspected all day in remote photovoltaic fields without external power sources, and there is no anxiety about battery life; Equipped with a fast charging interface, it can be fully charged in 2 hours and supports emergency power replenishment for mobile power banks in vehicles. The host is equipped with a large-sized backlit display screen, which provides clear and readable numerical values in strong light and low light environments at night. It supports single button automatic measurement mode, enabling one click start of high-voltage output, data acquisition, and automatic discharge throughout the entire process. Novice operation and maintenance personnel can operate it proficiently with simple training, greatly reducing the training cost for enterprise personnel.
The intelligent data storage and traceability function meets the requirements of compliance archiving. JW-J25 can store thousands of sets of insulation measurement data locally, and each record automatically saves the test voltage, insulation resistance, PI absorption ratio, measurement time, and equipment number. It supports one click export of complete detection reports, and the report format conforms to the standards of grid connection acceptance and power safety inspection data. It can be directly used for power station filing and safety inspection data submission. Equipment reserved firmware upgrade interface, Jiangsu Jingwei continuously updates photovoltaic insulation measurement algorithms, pushes upgrade packages to users for free, and continuously optimizes high-voltage measurement accuracy and anti-interference performance. At present, JW-J25 is widely used in photovoltaic operation and maintenance service enterprises, power testing units, safety and environmental departments of large photovoltaic groups, industrial and commercial energy management companies, and third-party electrical safety testing institutions. Jiangsu Jingwei provides insulation testing practical training, rapid after-sales maintenance, and annual equipment calibration guidance services to ensure the stable operation of equipment in all aspects. In the context of increasingly strict safety control in photovoltaic power plants, JW-J25 has built a standardized tool for insulation safety testing of photovoltaic DC systems with its core advantages of photovoltaic exclusive anti-interference technology, multi level high-voltage measurement, and portable safe operation. It can identify major safety hazards such as leakage and short circuit in advance, and build a strong electrical protection barrier for the long-term safe and stable operation of various photovoltaic power plants across the country.
Leakage current test, AC/DC withstand voltage insulation grounding tester, multifunctional electrical comprehensive tester