UL

UL, short for Underwriters Laboratories, writes safety standards for many kinds of products and tests products to check that they meet them. UL uses UL 1741, together with CSA C22.2 No. 107.1, to certify that PV inverters meet the National Electrical Code, the Canadian Electrical Code and IEEE 1547. UL also certifies inverters to UL 62109-1, together with the Canadian CSA 62109-1, for the same code and IEEE 1547 requirements. Inverter datasheets list UL grid certifications such as UL 1741 SA and UL 1741 SB, along with arc-fault testing to UL 1699B. Battery storage products list UL 9540, UL 1973 and UL 1642 as their safety standards. Equipment can be UL Listed to both US and Canadian safety standards, and the listing is tied to a UL file number shown in the product documents. Manufacturers also publish guides on using UL 3741 to make commercial PV installations simpler.

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• sentence 4: review: partial - The Generac row lists UL 1741 SA and SB as grid certifications and the SMA row lists UL 1699B, but neither passage says UL 1699B is an arc-fault test.
• sentence 7: review: partial - Solis does publish a UL3741 guide on using it for a simpler (and cheaper) installation for commercial inverter models, but the sentence says 'manufacturers' in the plural when only one manufacturer's guide is cited. -->