Whether the neutral line of a single phase circuit can be connected to the zero protection line

The zero line of the single-phase circuit can not be connected to the zero protection line, can not be connected to the ground wire, but can not be connected to the zero line end, otherwise once your equipment leaks, it will directly form a short circuit, causing a fire, and if the front end of the zero line is broken, then the leakage. If you can ensure that the neutral line will not be broken, and the short-circuit protection of the live wire is reliable, then you can connect the neutral line to the zero protection line.

Protective wire (PE wire): It is a grounding wire used to ensure personal safety and prevent electric shock accidents. The exposed conductive part of all equipment in the system (refers to the easily accessible conductive part that is normally unvoltage but may be voltage in the event of a fault.

For example, the metal shell and metal frame of the equipment, etc.) are grounded through the protective wire, which can reduce the risk of electric shock in the event of a grounding fault in the equipment. Protection neutral line (PEN line): It has the function of both neutral wire and protective wire, this kind of PEN line is commonly known as "zero line" in China, commonly known as "ground line".

The current flowing through the two wires of the household single-phase leakage protector is the same, and there is no problem of which one is more likely to burn out.

If any of the landlord's wires burns out, it must be that the wire has a large contact resistance when the line is pressed, and it is burned out by heating.

No! If your neutral wire is short-circuited, it will cause the electrical shell to have high voltage [220V] unsafe! It's better not to pick it up.

Absolutely not, you can not connect the ground wire, but you can't connect to the neutral end, otherwise once your equipment leaks, it will directly form a short circuit and cause a fire.

The three-phase four-wire system has a protection connection method, but it is not advocated now, and it is generally a three-phase five-wire system. Like you said, it's a single-phase circuit for domestic use, right? That's not compliant.

No! You can leave it alone.

Hello questioner.

Protective zero connection: Under normal circumstances, the metal part of the electrical equipment that is not charged is well connected with the neutral wire with metal or conductor. When a phase insulation is damaged and the phase wire of the power supply touches the shell, and the shell and conductor part of the electrical equipment are electrified, because the shell and the conductor part take the zero connection measure, the phase wire and the neutral wire constitute a loop.

Due to the large single-phase short-circuit current, the fuse of the line protection is blown out. As a result, the equipment is disconnected from the power supply, avoiding the possibility of personal electric shock injury.

Three-phase power supply system suitable for neutral grounding (some civil three-phase four-wire neutral grounding systems also use protective grounding, but it must be used with switches with leakage protection).

Connecting the device shell to the neutral line is to protect the neutral wire! If it is grounded, it is a protective ground wire, and grounding protection is not allowed in the system of neutral grounding, so zero protection is required! The function is the same, mainly to prevent the shell from being charged and causing electric shock accidents!!

The protection of the zero line generally refers to the repeated grounding of the zero line, in China's three-phase four-wire power supply system is not allowed to ground protection, so it is necessary to use the protection of the zero line for repeated grounding to ensure the safety of people and equipment, and the connection of the protection zero line is added at the entrance of the power supply with repeated grounding

The neutral line is repeatedly grounded, or the neutral line is worked to be grounded.

Zero connection protection with working zero line.

The working principle of zero connection protection: when the electrical equipment is working normally, the neutral line is not charged (or the voltage is very small), because the electrical equipment shell is connected with the power supply neutral line, there is no danger for the human body to touch the equipment shell.

When the motor and other electrical equipment "hit the shell and slip" to cause obstacles, the phase wire is short-circuited with the neutral line, and the short-circuit current is enough to make the fuse or circuit breaker installed on the power line play a short-circuit protection function, so as to cut off the power supply.

When the cable resistance is not considered, it is obvious that the voltage of the electrical equipment shell to the ground is 220V, which is very dangerous if the human body touches the shell; If the cable resistance is considered, where RO is the phase resistance and RN is the neutral resistance, assuming that the cross-section of the phase-wire cable is 2 times the cross-section of the neutral cable, the human body will be subjected to a voltage of 147 when it touches the shell, which is also very dangerous.

In general, the effectiveness of the protection zero connection lies in whether the short-circuit protection device of the line can quickly cut off the power supply.

1. Zero connection protection means that the shell of the electrical equipment is connected to the protection zero line, so that when the shell of the electrical equipment is in contact with the phase wire, a strong short-circuit current will be generated to cut off the power supply of the power circuit breaker and achieve protection.

2. The protection of the zero line is relative to the working zero line, and the two lines are the same friendly and stupid rush point, and the distribution room cannot be mixed, and each is responsible for it. There is a current in the working neutral line, which is used for the circuit of single-phase electrical equipment; The protection neutral line has no current, and is specially used to connect the electrical shell to play a protective role.

In the low-voltage three-phase four-wire system neutral direct grounding line, the construction unit should ground the terminal of the zero trunk line and branch line of the distribution line during installation, and the zero trunk line should be grounded every 1 km.

In addition to repeated grounding at the distribution room or main distribution box, the protection neutral line must also be repeatedly grounded at the middle and end of the distribution line. For distribution lines with a grounding point of more than 50 meters, the neutral line at the access user should still be repeatedly grounded, and the repeated grounding resistance should not be greater than 10 ohms.

The protection zero line must be repeatedly grounded, (the rear end of the working zero line is not allowed to be repeatedly grounded) what you said is that this protection zero line is grounded at the beginning and middle end, and it is best to be grounded in the middle of the multi-resistant shoot to ensure that it is well grounded and safe.

The grounding wire of each grounding device shall be made of more than two conductors, and the grounding device shall be electrically connected at different points. Aluminum conductors shall not be used as grounding bodies or underground grounding wires. Angle steel, steel pipe or round steel should be used for the vertical ground, and rebar should not be used.