The metal frames and cases of mains-powered welding rectifiers, transformers and voltage regulators and of engine-driven welding machines must be positively earthed locally throughout the work.

• 在整个作业过程中，电网电源驱动的焊接整流器、变压器、电压调节器和发电机驱动的焊机的金属框架和外壳均必须就地可靠地接地。