Cutting-edge technology for testing photovoltaic installations
The evolution of the photovoltaic industry demands instruments capable of meeting the challenges posed by state-of-the-art plants. Metrel equipment has been developed with the real-world needs of commissioning, operation, and maintenance engineers in mind, offering solutions ready for 1500 Vdc systems and high-current modules.
Its design incorporates advanced functions that enable testing in accordance with IEC 62446, integrating insulation measurements, I-V curves, open-circuit voltage (Voc), short-circuit current (Isc), polarity verification, protective continuity, and comprehensive string performance analysis into a single instrument.
A standout feature is the ability to measure string currents of up to 40 A DC. This allows for direct work with the latest high-power photovoltaic modules—including bifacial ones—addressing current and future market trends where many conventional devices begin to show limitations.
The Metrel platform also combines:
Compatibility with installations up to 1500 Vdc. Comprehensive Category 1 and Category 2 testing according to IEC 62446. Automatic correction of I-V curves to STC conditions. String performance evaluation via comparison with a theoretical model. Integration with environmental sensors for irradiance and temperature. Mass storage of results and automatic report generation. An intuitive interface designed to maximize field productivity.
The result is a solution that not only meets current regulatory requirements but also provides the technical capability needed to tackle next-generation photovoltaic projects with greater precision, efficiency, and reliability.
Metrel represents a future-proof investment, providing instruments ready for increasing module power outputs, utility company demands, and the latest international standards.
test on demanding conditions
The product range includes testing equipment for 1500 V DC or 1000 V DC systems. Among the instruments supporting 1500 V DC, the MI3114—which handles a maximum short-circuit current of 40 A—is compatible with IEC 62446-1 compliance testing, supporting all measurement procedures required for Category 1 tests. This includes specific PV measurements such as insulation resistance of PV strings, polarity, earth continuity, combiner box testing, short-circuit current (Isc) and open-circuit voltage (Uoc) measurements, as well as the calculation of measured results to STC values and comparison with the nominal values provided by the PV module manufacturer. Irradiance and cell temperature are measured in real time using a wireless remote unit. Furthermore, all Category 1 tests are consolidated into a single automatic test sequence, allowing the user to execute all tests by simply pressing the start button.
The MI3115, while supporting a maximum short-circuit current of 20 A, serves as an intermediate model between the MI3114 and MI3116; in accordance with the IEC 62446 standard, it incorporates both Category 1 and Category 2 measurements—adding, for instance, I-V curve analysis per string or group of strings, which is recommended for detecting mismatch, soiling, damaged modules, degradation, and connection issues, among other factors. It thus enables a comprehensive evaluation of array performance.
The MI3116 stands out as the most comprehensive unit, featuring a maximum short-circuit current of 40 A and full IEC-compliant testing covering both Category 1 and Category 2 measurements.
This range of PV installation solutions allows for complementary testing using power quality (PQ) meters to measure AC-side power, thereby facilitating a complete diagnostic analysis of the inverter.
