This standard establishes nominal voltage ratings and operating tolerances for 60-hertz electric power systems above 100 volts. It also makes recommendations to other standardizing groups with respect to voltage ratings for equipment used on power system
ANSI C84.1-2006 history
2020ANSI C84.1-2020 American National Standard for Electric Power Systems and Equipment -- Voltage Ratings (60 Hz)
2016ANSI C84.1-2016 Electric Power Systems and Equipment — Voltage Ratings (60 Hertz)
2011ANSI C84.1-2011 Electric Power Systems and Equipment-Voltage Ratings (60 Hertz)
2006ANSI C84.1-2006 American National Standard for Electric Power Systems and Equipment - Voltage Ratings (60 Hertz)