YBX3 series high-efficiency flameproof three-phase asynchronous motors (frame numbers H80~355) are made into flameproof type according to the requirements of GB/T 836.1-2021 "Explosive Atmospheres - Part 1: General Requirements for Equipment" and GB/T3836.2-2021 "Explosive Atmospheres - Part 2: Equipment Protected by Flameproof Enclosures" d ". The explosion-proof symbol is Ex db IIB T4 Gb. Its efficiency index meets the third level specified in GB 18613-2020 "Limits and Grades for Energy Efficiency of Electric Motors", and is applicable to equipment in Class II, Class A and Class B, Groups T1 to T4, where flammable gases or explosive mixtures of steam and air form. It is used as general power equipment.