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SGS in Spain has achieved recognition as an American Nationally Recognized Testing Laboratory (NRTL) and can now test and certify to the UL 1741 Supplement (SA) safety standard. This allows us to test and certify inverters, converters and other equipment for interconnected distributed generation in network support functions, making more intelligent and safe interconnections possible.

The second edition of the UL 1741 standard, issued in on September 7, 2016, distinguishes between two types of equipment:

  • Utility Interactive Inverter
  • Grid Support Utility Interactive Inverter (GSUI)

This version, including the supplement (SA), clears the way for improvements to general requirements established in the standard IEEE 1547 – Standard for Interconnecting Distributed Resources with Electric Power Systems. It allows for GSUI equipment to remain connected, despite stability issues. In turn, this will help the system to stabilize, creating better overall device efficiency.

Certain states in the US are now also issuing their own network interconnection requirements, to be verified using the testing methods referenced in UL 1741 SA. These tend to be the states with large numbers of solar power plants, such as California (Rule 21) and Hawaii (Rule 14). California has also recently announced UL 1741 SA as a compulsory requirement for PV inverters.

“Receiving NRTL recognition helps SGS deliver the global certification requirements of solar energy manufacturers. Our first cases have been successful, with high levels of customer satisfaction. Our team is focused on providing the right service to help manufacturers sell their products on a global scale,” said Susanna Serra, Global Business Development Manager for Renewable Energy in SGS.

All equipment certified under this safety standard will bear the SGS North America Listed Mark.

For more information, please contact:

Susanna Serra
Global Business Development E&E
SGS Tecnos, S.A.
www.sgs.com/ee

About SGS

SGS is the world’s leading inspection, verification, testing and certification company. SGS is recognized as the global benchmark for quality and integrity. With more than 90,000 employees, SGS operates a network of over 2,000 offices and laboratories around the world.