The contact resistance of a main bus-bar circuit is one of the key parameters

concerning safety and reliability of GIS.However

sometimes this resistance is not stable in production and needs to be adjusted repeatedly.This paper analyzes the factors which affect the contact resistance of main bus-bar circuit

and determines the major factors by comparing the measured data from different assembly processes.Consequently

corresponding control methods are proposed to make the products qualified

including improving and optimizing the assembly process of main bus-bar

and controlling the dimension of main part of GIS.