What is the cause of death from electric leakage in swimming pools?

Mr. Hu, who runs the water circulation system in Chongqing, is most concerned about the underwater leakage of swimming pool pumps. He has been engaged in this work for about 10 years. He told us that if the swimming pool leaks electricity, we can find the reasons from four aspects. The first reason is the water pump, such as the wet machine room and the wet motor. Water pipe leaks, wetting the motor, etc. Mr. Xiong from Bashu Middle School also analyzed the leakage of the water pump from the physical point of view. Firstly, it involved three kinds of wires in the water pump: live wire, neutral wire and ground wire. The grounding wire is connected to the water pump housing and leads to the earth. If the water pump itself leaks electricity and the shell is charged, it should flow to the earth through the ground wire, so that there will be no electric shock accident, which means that the probability of water pump motor leaking electricity through the ground wire is zero. The cause of the electric leakage, the problem may appear in the circuit, but it is unlikely to be the motor itself. Let's talk about the zero line first. Even if the zero line is broken, it will not cause people to get an electric shock. Because the zero line is the return line electricity, it finally returns to the substation and flows to the earth. Finally, the line of fire. If the motor is working, then there is only one possibility, and it should be where the outer skin of the live wire breaks and causes leakage. As for the reason of skin breakage, it may be that the temperature in the motor is too high, which leads to the skin breakage of insulating rubber and leads to conduction. Coupled with the vibration of the pump motor, it is likely to cause friction between the wire and the catheter. After a long time, the line of fire broke. Teacher Xiong suggested that the swimming pool should always check the terminals connected to the motor conduit. Then there is the cause of possible wire aging, which should also be considered. In short, if the water pump leaks electricity, only the live wire leaks electricity. But it is troublesome to check where it is missing. You should use a potentiometer, one end is grounded, and the other end is poked on the wire, and test it step by step. The closer to the leakage point, the higher the potential. The higher the potential difference, the more likely it is to be a place of leakage.