These requirements cover equipment incorporating solid state switching elements intended for starting@ stopping@ regulating@ controlling@ or protecting heating and other resistive loads@ having a-c voltage ratings above 1500 V@ up to 15 kV. The requirements do not cover variable speed motor controllers (power conversion equipment). These requirements cover equipment intended for use in ordinary locations in accordance with the National Electrical Code. Equipment intended for starting@ stopping@ regulating@ controlling or protecting electric motors or other electrical loads including refrigeration equipment are covered by the requirements the Standard for Medium-Voltage AC Contactors@ Controllers@ and Control Centers@ UL 347 or the Outline for Medium Voltage Motor Controllers@ Up to 15 kV@ Subject 347B. Where noted in this Outline@ requirements specified in the Standard for Medium-Voltage AC Contactors@ Controllers@ and Control Centers@ UL 347@ fifth edition@ apply to these products.