UL 60947-4-1A-2007 低压开关装置和控制装置.第4-1节:电流接触器和电动机起动器.电机电流接触器和电动机起动器
UL Standard for Safety for Low-Voltage Switchgear and Controlgear Part 4-1: Contactors and Motor-Starters Electromechanical Contactors and Motor-Starters Second Edition
This standard gives requirements for: contactors associated with overload and/or short-circuit protective devices; starters associated with separate short-circuit protective devices and/or with separate short-circuit and integrated overload protective devices; contactors or starters combined, under specified conditions, with their own short-circuit protective devices. Circuit-breakers and fuse-combination units used as short-circuit protective devices in combination starters and in protected starters shall comply with the requirements of IEC 60947-2 and IEC 60947-3, as the case may be.