Industrial contactors and starters - US standard (duty classes, switching endurance).
The standard covers industrial AC contactors, controllers (starters) and overload relays with rated voltages up to 600 V, including NEMA sizes 00–9, utilization classes and test requirements. The scope does not cover medium-voltage equipment - MV contactors in the USA are covered by UL 347 / NEMA ICS 3.
