The operation load of composite insulator includes normal (0mi) and abnormal (EMI) mechanical load. OML (orrjinary mechanical load) refers to normal mechanical load? This load represents the weight of a suspension group composed of conductors, fittings, spacers, etc. or the tensile load of conductors in a tension group without ice, taking into account the most frequent wind speed. This load and the corresponding temperature are determined by the user according to the most prevailing operating conditions.