Recently, we have continued to pay attention to an incident where the claw machine leaked and injured people. On the afternoon of September 25, we invited Zhao Chubei, a physics teacher at Hangzhou No. 2 Middle School, and Master Ma, a professional electrician, to disassemble a new claw machine, take a look at the internal structure and circuit conditions of the machine, and analyze the reasons why the claw machine may leak.
Ms. Zhou reported that the claw machine electric shock incident. Where is the problem? The merchant has not yet responded to it. To make a proof, we purchased this new claw machine.
Teacher Zhao and Master Ma first checked the inside and outside of the claw machine's collection port and confirmed the material of the material. Then, they opened the back cover of the machine together and checked the internal circuit status. It was observed that the back of the claw machine mainly includes the motherboard and the switching power supply , which are all installed on a wooden board. Master Ma said that this plays a certain insulating role.
Senior physics teacher in Hangzhou No. 2 Middle School Zhao Chubei : "The hole around the doll is filled with metal. ( Reporter : If you say your hand reaches in.) ( Electrician Master Ma Wei : If the shell is charged, it may be electric. ) (Reporter : This is our pickup, and its shell is actually a metal texture.)”
Electrician Ma Wei : "Go out from here, enter here, enter this plug, and then go to this, this is the switch of the claw machine, and then the power of the claw machine comes out from here, first enter the switch, and then power the driver power supply. After these two wires go in and out, they are all weakly powered."
Master Ma introduced that after the 220 volt current passes through the power supply, it becomes a safe voltage, and then outputs to the machine motherboard and to the various components of the claw machine. In order to further view the internal situation of the machine, Master Ma removed all the main components such as the motherboard, switching power supply, etc. in the machine.
Senior Physics Teacher in Hangzhou No. 2 Middle School Zhao Chubei : "A power import is because it has many places to control, a sky car, a joystick, and the light will light up. They all go out from this motherboard. It should be different areas, so they are responsible for different functions."
Electrician Master Ma Wei : "The power supply is 220 (volts) coming in, 110 (volts) can come in, and it can be used. It becomes 12 volts, 5 volts, and 24 volts. (This is an output current.) The voltages it may use in this machine are different, and some aspects may be used."
Senior Physics Teacher at Hangzhou No. 2 Middle School Zhao Chubei : "If
During the disassembly, Teacher Zhao and Master Ma discovered that there were some hidden dangers inside the machine, mainly including: some circuits of are not fixed, and the circuit plug does not have protective shells, etc. . In response to these problems, Teacher Zhao also gave rectification suggestions.
Senior Physics Teacher, Hangzhou No. 2 Middle School Zhao Chubei : "There are some wires, which are not screwed with that kind of screw. It may be inserted, and it is easier to fall out. The metal wire of can have some insulating shells on the outside, so just put it in. If
dismantling investigation was completed, Master Ma restored the machine and used universal meter to test several locations where there may be leakage. Master Ma said that because most of the line interfaces are plug-in and are not exposed, , the possibility of leakage is lower .
Electrician Master Ma Wei : "4.8 volts should be safe. Now it is on-off , which is the ON or OFF gear. It's now accessible. (Umage means normal?) Normal. buzzer is calling, which means that ground line has been connected. "
Senior Physics Teacher Zhao Chubei : "Maybe there was a leakage in some parts of the circuit inside it, and then the protection device that was grounded at the same time (maybe) also had problems. One is that maybe its ground wire is not connected, and there is also a possibility that it may not be installed in our socket. is these various factors. Maybe it is combined and happens to that machine. ”