Method for adjusting trip sensitivity of thermal overload protection apparatus

摘要

A method for adjusting a trip sensitivity in a thermal overload protection apparatus so as to effectively set and adjust a trip operation current, comprising: setting an adjusting reference point; measuring a normal position of bimetals; measuring a moving distance at a time of trip operation of a trip latch mechanism; deciding an assembling position of a shifter mechanism based on the measured moving distance at the time of trip operation of the trip latch mechanism, information on a trip distance between a pre-determined shifter mechanism and the trip latch mechanism and information on a size of the shifter mechanism; conducting a predetermined over current to the thermal overload protection apparatus; measuring a conducting time of the overcurrent until a trip occurrence; calculating a difference between the conducting time measured in the measuring step and a predetermined trip time by converting a rotation angle; and marking a graduation of a set trip operation current by the rotation angle calculated in the calculating step.