In the installation and use, the safety isolation transformer Class III tools, Class II leakage protectors, Class II, III tool box and power supply devices should be far away from the workplace. The power lead wire of the tool shall be made of tough rubber covered wire or plastic sheathed soft copper wire. There shall be no connector in the middle, and any length or disassembly shall not be allowed. Protective grounding resistance shall not be greater than 4Ω. Do not dismantle the protective cover of the running parts during the work, and replace the tool and abrasive tool to stop.

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 General workplace, in the use of class Ⅰ tools, should be equipped with earth leakage protection, isolation transformers and so on. Class II or III tools should be used in damp places. If class I tools are used, an earth leakage protector with an operating current not exceeding 30μA and operating time not exceeding 0.1s must be installed. In boiler, metal container, pipeline operation, should use Class III tools, or with Class II leakage protection device, the leakage current protection device operating current is not greater than 15μA, action time is not greater than 0.1s. In special environments such as damp heat, rain and snow, the presence of explosive or corrosive gases and other operating environments, should be used with the appropriate level of protection and safety technology tools.