N stands for zero line and is the abbreviation of the English word NEUTRAL. The line is blue, and there is a PE line, which represents the ground wire. The color is yellow and green, commonly known as flower line.
Two wires in the lighting circuit, one is called live wire and the other is called zero wire. The difference between live wire and neutral wire lies in their different voltages to ground: the voltage of live wire to ground is 220 V; The voltage of neutral line to ground is equal to zero (it is itself grounded).
So when one part of a person touches the fire line and the other part stands on the ground, the voltage between these two parts of the person is equal to 220V, and there is a danger of electric shock. Instead, people grab the zero line with their hands. If a person is standing on the ground and the voltage between the neutral line and the ground is equal to zero, then the voltage between all parts of the human body is equal to zero, and there is no danger of electric shock.
Extended data:
Distinguishing method of zero line, live line and ground line:
1. Color: In power cables, yellow, green and red respectively represent phase A, phase B and phase C (three-phase live wire), blue represents zero line, and yellow and green represents ground wire.
2. Distinguish with an electric pen: When testing the live wire with an electric pen, the neon tube will glow, but the zero line will not.
3. Use voltmeter to distinguish: the voltage between different phase lines (i.e. live wires) is 380V, the voltage between phase lines (live wires) and neutral lines (or good grounding bodies) is 220V, and the voltage between neutral lines and good grounding bodies is 0 V. ..
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