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有—台台钻,手触台钻有漏电现象,电笔测氖管发亮。把台钻开关断开也有上述情况。 经测该设备接零没有保护接地。保护接地就是把电气设备的金属外壳、框架等用接地装置与大地可靠地连接,它适用于电源中性点不接地的低压系统中。如果电气设备的绝缘损坏,使金属导体碰壳,由于接地装置的接地电阻很小,外壳对地电压大大降低。当人体与外壳接触时,外壳与大地之间形成两条并联支路,电气设备的接地电阻愈小,通过人体的电流也愈
There - Taiwan bench drill, hand touch the table there is a leakage phenomenon, neon light pen pencil. The bench drill switch off the above situation. The device measured zero access zero ground. Protective grounding is the metal shell of electrical equipment, frames and other grounding devices connected to the earth and reliable, it is suitable for low voltage power supply neutral point system. If the electrical equipment insulation damage, the metal conductor housings, due to grounding device grounding resistance is very small, the shell to ground voltage is greatly reduced. When the human body is in contact with the shell, two parallel branches are formed between the shell and the ground. The smaller the grounding resistance of the electrical equipment, the more the current passing through the human body is also