Two cold knowledge of plug
First. The life-saving three millimeters on the triangular plug:
Do people often complain that the three-wire plug occupies the space? It is not as convenient to use as the two-wire plug. I can’t wait to change the three-wire plug into a two-wire plug. In fact, one of the three-wire plugs is a grounding wire. The grounding wire is not a redundant design, but a "help" String". It is usually connected to the shell of electrical equipment. Once there is a leakage, most of the current flows to the earth from there. In the event of an electric shock, only a small amount of current flows into the human body.
So, where is the three millimeters of the three-wire plug? Yes, it's on the rescue line. Usually the ground wire is three millimeters longer than the neutral wire and the live wire. The reason for this design is that when the plug is inserted into the triangular socket, the ground wire is first connected and then the neutral wire is connected. Therefore, if there is a potential leakage hazard in the electric facilities, the grounding wire has been led to the earth in advance, which also avoids the electrical accident of electric shock!
Second. What are the two small round holes of the two-angle plug used for?
1. Fixing the plug: When the plug is inserted into the socket, there will be a force to fix the plug, which comes from the shrapnel inside the socket. The shrapnel has a small protrusion that just fits into the hole of the plug and gives the socket one Fixed force.
2. Locked plugs: Some sockets are locked. After inserting them, press a switch to insert a metal rod into the hole to avoid being pulled out by others, such as the plug on a vending machine.
3. Factory packaging: Pass a plastic strip through this hole, which is equivalent to a package and cannot be used unless it is opened. For example, the factory can wear a plastic strip with instructions on it to ensure that you must tear the plastic strip and see their instructions before using it.
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