The Ministry of New and Renewable Energy (MNRE) has released draft guidelines for the series approval of solar photovoltaic (SPV) inverters for testing in laboratories under the Solar Systems, Devices and Components Goods Order, 2025. These guidelines apply to SPV-based off-grid, grid-tied, and hybrid inverters and are intended to support compulsory registration with the Bureau of Indian Standards. A product family is defined based on a maximum configuration of components and sub-assemblies, with all models required to share the same hardware and firmware. The highest-rated inverter model in a series must undergo testing for IS 16221 (Part 2):2015 and IS 16169:2019 standards, while each individual model must be tested separately for IS/IEC 61683:1999, IS 17980:2022, and IEC 62891:2020 due to variations in efficiency. Testing fees are charged only for the highest-rated model in a family for the IS 16221 (Part 2):2015 and IS 16169:2019 standards, while model-wise testing fees and individual testing reports will be applicable for the IS/IEC 61683:1999, IS 17980:2022, and IEC 62891:2020 standards.The product label of each model in the series shall be included in the test reports.
The documentation required includes datasheets, bill of materials, schematics, enclosure diagrams, principal control board (PCB) layouts, safety certificates, user manuals, and details on firmware versions. Product marking must comply with IS 16221 Part II Clause 5, including manufacturer name, model number, serial number, input/output voltage, current and frequency, and ingress protection (IP) rating. Two samples of the maximum-rated inverter from the family must be submitted, complete with handling, mounting and connection instructions. All models in a family must share the same rated input/output voltage, frequency, number of output phases, PCB design, control algorithm, power state topology, insulation class, and cabinet design. Different cabinet designs must undergo separate IP testing. The inverter safety tests must follow IS 16221 (Part 1):2016, and the test sequence should involve communication with manufacturers for critical safety verifications. For standalone or off-grid inverters, IS 16169 does not apply.
If a test fails in sequence 1 or 2, the manufacturer must submit a new sample and repeat the respective tests, along with a review of components and construction. Only one failure is permitted per test sequence; a second failure results in overall test rejection. Brands and respective model numbers must be listed in the test report, with test samples not required for each brand if representative labels are included. Products manufactured at different locations must undergo separate testing. Retesting of IS 16169 is only required if internal component changes affect performance.
