The Ministry of New and Renewable Energy (MNRE) has issued guidelines for series approval of solar PV inverters for conducting testing in labs.
Here we bring you few points that you should know about the new guidelines issued by the ministry:-
The guidelines has been designed to facilitate test labs to approve the product family including change in design and materials for the solar inverters for their compulsory registration with Bureau of Indian Standards (BIS) and for the implementation of the Solar Photovoltaics Systems Order.
The guidelines are applicable for solar PV-based off grid, grid-tied and hybrid inverters of capacities up to 150 Kilowatt.
Manufacturer have to submit a declaration about the series of the product while submitting the samples for testing.
Out of the entire range of models intended to be covered under registration, the highest rated model shall be tested to cover the entire range of family.
The lab will be required to charge the cost of testing only for the highest-rated inverter size model and the product label of each series model will be placed in the test report.
If there is a change in construction, material or components in the family then the product will be submitted to test labs for fresh testing.
Products having different Hardware Architecture and Firmware functionality shall be tested separately. Within the Family the components with different ratings (Power/current) can be allowed provided the Inverter with max rated component (such as EMC filters, Capacitors, Transformers, Inductors, IGBT/Mosfets, etc.) is tested.
All the models under one family shall have same rated Input/Output voltage, Same frequency and No. of Phases at output, Same PCB design and layout, same power stage topology, same insulation class (low or high frequency transformer or transformerless), same control algorithm/firmware, Same cabinet design and class of construction. If the cabinet design architecture is changing between various models in the family (keeping the same Internal Hardware like PCB layout between various models in the family), then all the different cabinet designs are to be tested or verified for Ingress Protection by either testing it at NABL approved laboratories or test reports shall be submitted from ISO/IEC 17025/ILAC accredited laboratories.
Inverters having PV voltages rated greater than 1000Vdc and greater than 415Vac are not covered in these guidelines.