Alternating current has neither positive nor negative. N and L mean live and neutral wires.
The neutral line is a line drawn from the neutral point (N) on the secondary side of the generator or transformer. It forms a loop with the phase line (L) to power the electrical equipment. Normally, the neutral line is repeatedly earthed (PEN) with the protective earth wire (PE) at the neutral point (N) on the secondary side of the transformer, thus playing a dual role of protection.
The live wire in a DC circuit refers to the wire connected to the positive pole.
Detailed information:
1. AC power
AC power The wires are divided into neutral wire (marked with the letter “N”: neutral wire) and live wire (marked with the letter “L”: live wire). There is also a ground wire connected to electrical appliances - a wire connected to the ground ; the live wire, neutral wire and ground wire are all wires connected to the three-hole socket. A sinusoidal oscillating voltage difference is maintained between the live wire. and the neutral wire.
Since the ground and neutral wires have the same potential, the voltage difference between the live wire and the ground wire also maintains a sinusoidal oscillation. When the human body contacts the live wire, the current from the live wire passes through the human body to the ground or neutral wire, and an electric shock accident occurs. However, you won't be electrocuted if you touch neutral. thread.
Connect the shell of electrical devices that can conduct electricity to the ground wire. In the event of a leak, current will flow directly into the earth through the earth wire without passing through the body, thus avoiding electric shock. accidents.
2. Circuit differences
New linetre (N): Mainly used in the working circuit, the main line drawn from the neutral point of the generator and transformer and grounded.
Earth wire (PE): Not used for working circuit, only used as protective wire. Using the absolute "0" voltage of the earth, when a leakage occurs in the equipment shell, the current will flow quickly into the earth, even if the PE line is open circuit, it will flow into the earth from the nearby earthing body. (Bring the main line from the neutral point of the transformer to ground and repeat grounding every 20 to 30 meters)
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