If mains power is used, the workpiece must be positively earthed using a well-protected earthing wire connected at both ends by bolted lugs or secure screw clamps.是什么意思_If mains power is used, the workpiece must be positively earthed using a well-protected earthing wire connected at both ends by bolted lugs or secure screw clamps.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句