Difference between neutral point, zero point, neutral wire, ground wire, and grounding

The difference is: Neutral wire (N): The main conductor that is drawn out from the grounded neutral point of the transformer. It is mainly used in the working circuit; the voltage generated by the neutral wire equals the line resistance multiplied by the current in the working circuit. Due to long-distance transmission, the voltage generated by the neutral wire cannot be ignored, making protective measures for personal safety unreliable. Ground wire (PE): A main conductor is drawn from the grounded neutral point of the transformer; according to standards, it is re-grounded every 20–30 meters. It is not used in the working circuit, but only as a protection wire. By utilizing the absolute \"0\" voltage of the ground, when there is a leakage in the equipment’s casing, current will flow rapidly into the ground; even if the PE wire is open-circuited, current will still flow into the ground through nearby grounding elements. When the power supply side (transformer or generator) or the load side is connected in a star configuration, the common point at which the beginning (or end) of the three-phase coils are connected is called the neutral point, or simply the midpoint. The neutral point of a split power supply is divided into the neutral point of the power supply and the neutral point of the load. The wire leading from the neutral point is called the neutral wire, or simply the neutral line. If the neutral point is directly connected to the grounding device to obtain the reference zero potential of the earth, then this neutral point is called the zero point, and the wire leading from the zero point is called the neutral wire.

Very comprehensive, I’ve learned it! I must memorize this this time; otherwise, over time, if anyone asks, I’ll likely not be able to explain it properly!

The star connection point of a transformer is the neutral wire, and generally this neutral point is connected to ground; in other words, the resistance between the neutral wire and the ground wire is very low. 1. In terms of color, the neutral wire is standard blue, while the ground wire (protective neutral wire) is yellow-green colored; in the past, black wires were also used. 2. The main difference between the neutral wire and the protective neutral wire is that the protective neutral wire needs to be connected to ground multiple times, whereas the neutral wire shall not be connected to ground. [TN-S] – it’s also necessary to consider what type of power distribution system is being used. TN_C means that the neutral wire and the ground wire share the same conductor, while TN_C_S means that they share part of the conductor and are separated at other points

In an electrical lighting circuit, there are two wires: one is called the live wire, and the other is called the neutral wire. The difference between the live wire and the neutral wire lies in their voltages with respect to ground: the voltage of the live wire with respect to ground is 220V ； The voltage of the neutral wire with respect to ground is zero (it is connected to the ground itself). So when one part of a person comes into contact with the live wire while another part remains on the ground, the voltage between these two parts of the body is 220V, which poses a risk of electric shock. On the other hand, even if one tries to touch the neutral wire with their hand, as long as the person is standing on the ground, the voltage of the neutral wire with respect to the ground is zero; therefore, the voltage between different parts of the person’s body is also zero, and there is no risk of electric shock. If the live wire and the neutral wire come into contact, the voltage between them is 220 volts, and the resistance at the point of contact is almost zero. As a result, the current becomes extremely high, generating a great deal of heat at the point where the two wires touch. This heat produces electric sparks, and the temperature at those sparks is high enough to melt the metal wires. Grounding is the most important task in the safety technology of electrical equipment, and it should be taken seriously.

The neutral wire refers to the neutral conductor of the transformer； A ground wire is a wire that is connected to ground. The functions of the two are different: the neutral wire is used for power transmission, while the ground wire serves a safety protection purpose.