1, n line and PE line * * *;
2.N line and PE line are connected in reverse;
3. Equipment leakage caused by short circuit between phase wire and ground wire;
The earth is not equipotential. If your ground wire is connected to the earth in different places, it will cause a potential difference.
5. There are also interference problems such as high frequency of interference sources;
6. Finally, there is a large current flowing near the PE line, and some stray current will be conducted to the PE line through the earth.
It is not difficult to solve the threat of environmental electrification. For example, Haier water heater developed the patented technology of "anti-electricity wall" as early as 200 1. In case of environmental leakage, this technology can reduce the voltage of 220v in the tank to below the absolute safe voltage 12v that human body can bear (calculated by human body resistance), that is to say, even in unsafe electricity environment such as "live ground wire".