1. The color of the fire wire is red, that is, the red line commonly used in the circuit, which is represented by the letter L and abbreviated as L(LIVE) in English.
2. The color of the neutral line is blue, that is, the blue line is generally used in the circuit, which is represented by the letter n and abbreviated as n (neutral) in English.
3. The colors of grounding wire are yellow and green. Yellow and green lines (commonly known as flower lines) are generally used in the circuit, which are represented by the letter PE, abbreviated as PE (Protected Land) in English.
Note: In order to make alternating current have convenient power conversion function, power transmission usually adopts three-phase four-wire system. The three heads of three-phase electricity are called phase lines, and the three tails of three-phase electricity are called zero line together, which is also called "zero line". The reason why it is called neutral line is that at the moment of three-phase balance, there is no current flowing through the neutral line, and then it is directly or indirectly connected to the earth, and the voltage difference with the earth is close to zero.
The earth is a good conductor, and the grounding wire is short-circuited with the earth through the buried electrode. The transmission of commercial power is a three-phase mode with a neutral line. When the three phases are in balance, the current of the neutral line is zero, commonly known as the "zero line". Another characteristic of the neutral wire is that it is short-circuited with the ground wire at the input end of the total distribution of the system, and the voltage difference is close to zero. There is a voltage of 220 volts between the three-phase line and the neutral line of three-phase electricity, which will cause electric shock to people, commonly known as "live wire".
In electrotechnics, the AC voltage connected to the power line is 220 volts (V for short), and there are two lines in the line, one is called "zero line" and the other is called "live line". In electrical engineering, it is usually called neutral fire line or 10 1 fire fighting.
Circuit switches at home usually cut off the live wire and are equipped with leakage protectors to prevent personal electric shock accidents.