Method 1: Distinguish from the color of wires. Yellow, green and red are all active lines, and there is only one zero line color, that is, light blue; The ground wire is two-color wire.
Method 2: Test with an electric pen. After power on, use the digital electroprobe to detect the connectors of the three wires respectively, and see the voltage value on the digital electroprobe; The highest voltage value is the live wire, the lowest is the ground wire, and the middle voltage value is the zero wire.
How to connect the socket to be qualified?
- The wire color of socket wiring shall be correct. The outgoing line in the box shall be connected in parallel except the end, and the branch shall be connected to the socket. The arch head (continuous wire) connection is not allowed;
- The single-phase two hole socket faces the right hole (or upper hole) of the socket and is connected to the phase line (L), and the left hole (or lower hole) is connected to the neutral line (N);
- The single-phase three hole socket faces the right hole of the socket and is connected to the phase line (L), the left hole is connected to the neutral line (N), and the PE or PEN line is connected to the upper hole;
- The PE or PEN line of three-phase four hole and three-phase five hole sockets shall be connected to the upper hole, and the phase sequence of three-phase socket wiring in the same place shall be consistent;
- The grounding terminal (E) of the socket is not connected with the neutral line (N) terminal, the PE or PEN line is not connected in series between sockets, and the N line of the socket is not confused with the PE line;
- When lighting and socket are laid in separate circuits, sockets and lighting or sockets and socket circuits shall not be confused.
What are the precautions for power socket wiring?
Although many people have learned physics in school, many people have not really applied it to real life, so they need to study hard. Before wiring the power socket, we should first understand that the copper wires inside the wires are interlaced and twisted. Only in this way can we ensure that the wire connector will not be ignited, short circuited or have poor contact. Of course, this is also a basic skill for each electrician. If the owner wants to wire by himself, this must be clear.
If you encounter a spark or short circuit when wiring, don’t panic. In fact, it is not so difficult to deal with it. This situation is mostly caused by the absence of the correct connector. After the connector is loose, the high load current will produce electric ions when it passes through. The electric ions repel each other like welding spatters. At the same time, the temperature also rises. And soon, if it can be stuck, it will be energized. If it cannot be energized, it will form a short circuit.
For safety, we need to do a simple treatment after connecting the wires. The method is also very simple. You can stick black insulating fireproof tape at the connection position of the wires. This is important. Its function is mostly insulation and also fire protection. Only in this way can we get a lower limit for electricity safety.
However, many people no longer use the method of pasting insulating tape. They will go to the building materials store to buy a wire cap, which is a small tool specially used for wire connection. It is simple and safe to use. Generally, the insulating tape is not needed when using the threading cap. It is worth noting that the power socket connection must be arranged orderly, and different lines must be marked differently. It is convenient for maintenance and inspection. Generally, high voltage lines and low voltage lines need to be marked, while red lines are often used for live lines, and blue lines are used for zero lines. Some ground wires are gray and others are yellow. This facilitates later maintenance.