Since the development cycle of new models for automobiles is getting shorter, it is necessary to apply OLP (off-line programming) of welding robot system. However, in the robot system in which the existing welding cable is externally installed, the interference of the cable restricts the operation area of the robot. Therefore, it is troublesome to modify the robot program downloaded from OLP (Off-line Programming) after placing the robot in the factory need. In recent years, welding robots equipped with welding cables that overcome these shortcomings have been released by foreign advanced companies and are expected to become the mainstay of the welding robot market within the next three years. In order to secure competitiveness of the automobile manufacturing process and the domestic welding robot system, a robot system suitable for a rapid product development cycle and a welding system capable of completely managing defects of the welding quality in the manufacturing process are integrated development is essential.