
Long term exposure of photovoltaic systems to outdoor environments, such as cable aging, damaged insulation layers of components, and moisture and water ingress of wiring terminals, can cause a decrease in insulation performance, resulting in leakage and PID effects. In severe cases, it can lead to equipment damage and even personal safety risks. Insulation resistance testing is an essential safety inspection item for photovoltaic system installation acceptance and annual safety inspection. By measuring the insulation resistance value, it can intuitively evaluate the electrical isolation status of components, cables, combiner boxes, and inverters on the DC side, and detect potential safety hazards in advance. In response to the high voltage characteristics of photovoltaic DC systems, Jiangsu Jingwei Technology has developed the JW-J25 insulation resistance tester, which is customized and developed for the photovoltaic industry. It balances testing accuracy, operational safety, and portability, providing professional solutions for electrical safety testing of photovoltaic power plants. Leakage current test
The JW-J25 insulation resistance tester is equipped with a high-precision DC high voltage testing unit and a precision sampling circuit, adapted to the mainstream voltage level of photovoltaic systems. It can output multiple levels of testing high voltage, accurately measure insulation resistance, complete polarization index testing, and fully evaluate the insulation medium state. The instrument is specially optimized for the residual voltage scenario of photovoltaic DC, with a complete safety protection mechanism and built-in automatic discharge function. After the test is completed, the residual charge of the tested circuit is automatically released to avoid the risk of electric shock caused by high-voltage residual and ensure the personal safety of on-site operators. The instrument is equipped with an intelligent self checking module, which can complete circuit self checking when turned on, identify problems such as damaged test lines and abnormal wiring, avoid measurement result distortion caused by incorrect wiring, reduce the probability of on-site misoperation, and is very friendly to frontline operation and maintenance personnel.
The equipment fully considers the outdoor operation scenarios of photovoltaics, and adopts a portable structural design. The shell is sturdy and impact resistant, and the protection level is suitable for complex outdoor environments. The entire equipment is of moderate weight, making it easy for operation and maintenance personnel to carry it to various testing points. The human-computer interaction interface is simple and intuitive, with a large screen displaying key information such as test voltage, real-time insulation resistance values, polarization index, etc. The testing process is simple and clear. Operators follow the specifications to complete the wiring, select the corresponding test gear to start the measurement, and wait for the reading to stabilize to obtain effective detection data, greatly reducing the threshold for using professional instruments. The instrument supports local storage of test data and can export test records, facilitating the establishment of power station safety archives and providing measured data support for completion acceptance and safety assessment reports.
During the entire lifecycle of photovoltaic projects, the JW-J25 insulation resistance tester plays an irreplaceable role in ensuring safety. At the completion and acceptance stage of the project construction, insulation testing of components, cables, and combiner equipment shall be carried out in accordance with national standards, and insulation damage caused by the construction process shall be investigated. After confirming that the system insulation indicators meet the standards, it shall be put into grid connected operation to avoid safety hazards from the source. In the daily operation and annual safety testing of the power station, regular insulation resistance testing can timely capture faults such as cable aging, component insulation layer moisture damage, and junction box water ingress. Disposal can be completed before the fault erupts into an accident, avoiding problems such as leakage, PID attenuation, and equipment burnout. Whether it is a large-scale ground photovoltaic power station or a distributed photovoltaic project for industrial, commercial, or household use, this equipment can be used to conduct safety inspections. At the same time, it can also be used for insulation and voltage withstand sampling in component manufacturing enterprises, completing component insulation performance factory verification, and controlling product quality at the factory.
Photovoltaic safety is an important issue that cannot be ignored in the development of the new energy industry. The root cause of many electrical accidents is the failure to detect insulation degradation in a timely manner. In the past, some sites used a universal megohmmeter for photovoltaic testing without adapting it to the high-voltage working conditions of photovoltaic DC, resulting in operational risks and measurement deviations. Jiangsu Jingwei JW-J25 Insulation Resistance Tester is deeply tailored to the safety requirements of the photovoltaic industry, combining measurement accuracy, operational safety, and portability to provide reliable domestic testing tools for power plant owners, operation and maintenance service providers, and third-party testing institutions. With the continuous expansion of domestic stock photovoltaic power stations and the increasing demand for electrical safety inspections, the JW-J25 insulation resistance tester will continue to provide protection for the safety of photovoltaic systems, help the industry establish a normalized safety inspection mechanism, ensure the safe and stable operation of photovoltaic assets, and promote the safe and high-quality development of the photovoltaic industry.
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