This revision of ANSI/UL 61800-5-1 dated February 11, 2021 includes the following changes: – Typo Corrections in Table 4.3.5.3.1DV.3 – Editorial Correction in Clause 4.1 to Align with IEC Text Please note that the national difference document incorporates all of the U.S. national differences for UL 61800-5-1. UL 61800-5-1 is based on IEC 61800-5-1, second edition (published July 2007).