Three phase four wire line voltage is low, what is the three phase four wire voltage

If the line voltage is low, check whether the phase contact of the incoming line is good.

This is due to the open circuit of the zero line in the three-phase four-wire power supply line, under the ideal working state, if the three-phase load is evenly distributed, the current on the zero line is zero, but in the actual work, often the three-phase load can not be distributed very evenly, so there must be a zero line to keep the phase voltage of the three-phase balanced.

When the neutral line is disconnected, the phase voltage of the one-phase circuit with a large load will be very low. Therefore, in the three-phase four-wire power supply system, it is clearly stipulated that the neutral line shall not be connected to any switch, insurance, circuit breaker and other protection devices to prevent damage to electrical equipment due to the three-phase voltage imbalance caused by the disconnection of the neutral line.

There seem to be a few questions with your question; 1. What is the so-called machine (it seems that it is not an electric motor, but a three-phase four-wire input transformer with star connection) You don't make it clear here. 2. The concept of line voltage and phase voltage seems to be a bit confusing (the voltage between phases is called line voltage, and the voltage between phase and zero is called phase voltage). 3. The two groups you measured are 220V and the other group is 100V, which seems to be the phase voltage.

4. You didn't mention what the output voltage of the security device is. According to what you said, the analysis of the causes of the failure is about the next door, which causes 1. The load imbalance of the three-phase power supply causes serious zero drift. 2. Three-phase imbalance caused by poor contact of security devices.

3. Zero-line access and troubleshooting. I seem to think it's an illusion with a certain compulsive priming. Make the original defect more hidden.

Whether it is caused by device connection.

Question 1: What is the voltage of each line of three-phase four-wire electricity? Hello, The voltage between the three-phase four-wire phase wire and the phase wire is called the line voltage of 380V.

The voltage of each relative neutral line is called the phase voltage, and the voltage is 220V.

Hope mine is helpful to you

At the same time, I hope you can be in time

Question 2: What is the voltage of the three-phase four-wire system? Hard!

In the three-phase four-wire of the 10kV substation and distribution system, the voltage between the live wire on the low-voltage side (output) and the live wire is about 370 410V, and the voltage between the live wire and the neutral line is about 210 230V. In the three-phase four-wire of the 380V 220V substation and distribution system, there are about 210 230V between the live wire and the live wire on the low-voltage side (transmission), and about 110 130V between the live wire and the neutral line.

Question 3: What is the voltage of each live wire of three phase and four wires? The voltage of each live wire to the neutral wire is 220V, and the live wire to the live wire is 380V

Question 4: What is the line voltage? What is the phase voltage? The line voltage is 220V and the phase voltage is 380V

Question 5: How many volts is the most suitable for the three-phase four-wire line voltage The three-phase four-wire line voltage of 380 volts is the most suitable, which is the specified value.

Question 6: Why is the three-phase four-wire 380V? The so-called three-phase four-wire system refers to three phase wires plus a neutral wire, the line voltage is 380 volts, and the phase voltage is 220 volts, to put it bluntly, the voltage of two live wires is 380 volts, and the voltage of one live wire plus one neutral wire is 220 volts.

Question 7: What is the line voltage of China's three-phase four-wire current V The three-phase four-wire voltage is 220 380V. 380V between phases and 220V between phases and neutrals.

Question 8: Does three-phase electricity 380V refer to its phase voltage or line voltage? Three-phase electricity 380V refers to its line voltage 1, three-phase electricity 380V refers to the line voltage.

Line voltage refers to the voltage between the phase wires and the phase wires, whereas phase voltage refers to the voltage between the phase wires and the neutral wires. 2. For the triangular wiring power supply system, because the three-phase coils are connected end to end, the voltage (line voltage) at the head of the coil and the head of the other phase coil is also the voltage (phase voltage) at the end of the coil itself. 3、?

For star-wired power supply systems, the line voltage is a multiple of the phase voltage.

Question 9: What is the power of the three-phase four-wire phase voltage 380V current is 20A? Power p = 3 * phase voltage u * phase current i * power delay = line voltage * line current.

Line current = phase current.

The so-called line voltage refers to the voltage between lines 380V, and the phase voltage is 220V between lines and zero.

Phase voltage: The voltage between the live wire and the neutral wire. The phase voltage in our country is 220 volts, 50 Hz.

Line voltage: The voltage between the live wires and the live wires. The line voltage in China is 380 volts, 50 Hz.

Phase voltage, the voltage between the three-phase transmission line (live wire) and the neutral wire is called phase voltage. For example, the voltage in the three-phase four-wire system in the daily electricity system is 380 220V, that is, the line voltage is 380V, and the phase voltage is 220V.

Line voltage, the voltage between each line (live wire) of the three-phase transmission line is called the line voltage, and the size of the line voltage is a multiple of the phase voltage.

Difference Between Line Voltage and Phase Voltage:

For phase voltage, it is generally understood as the voltage between phases, that is, 380V, and the line voltage is understood as 220V.

The phase voltage refers to the voltage between the phase wire, that is, the live wire and the neutral line, and the line voltage is the voltage of any two live wires on the line, that is to say, the phase voltage should be 220V, and the line voltage is 380V.

What comes out of the power plant are three live wires (line voltage). In the use of a transformer to boost the voltage to transport out, the point used is to use a step-down transformer to step down to 400V (still the voltage of the three live wires).

The neutral wire is drawn from the contacts of the three sets of coils of the winding of the step-down transformer, and the transformer is star-shaped, and the four wires here are aligned.

In the receiver through the electric cabinet respectively received the user (load). The three live wires are generally named A, B, C, and the neutral line is n. With a line voltage of 380V, it is connected to A, B, and C. Families are using an, bn, cn. Both 220V phase voltage.

The three-phase four-wire system is the power of electricity, and the voltage is 380V.

L phase (live wire), n middle line (neutral line).

Phase wire: In order to make the alternating current have a very convenient power conversion function, usually three-phase sinusoidal alternating current is used for industrial electricity, and the current phase (reflecting the direction of the current) is 120 degrees different from each other. Usually we refer to each of these wires as phase wires (live wires).

Neutral line: The neutral line is the line drawn from the neutral point (n) on the secondary side of the transformer, which forms a loop with the phase wire (L) to supply power to the electrical equipment. Under normal circumstances, the neutral line is repeatedly grounded (PEN) with the protective ground wire (PE) at the neutral point (N) on the secondary side of the transformer, which plays a double protection role.

Summary. Three-phase four-wire has no load, two-phase voltage is high and one phase is low, three-phase four-wire two-phase voltage is high and one phase is low, which may be a serious imbalance of three-phase load. Three-phase four-wire power supply system with three live wires and one neutral wire.

The voltage between the three live wires is a line voltage of 380 volts. Between the three live wires and the neutral wire is a phase voltage of 220 volts. If the three-phase load is balanced, the neutral point potential on the load side is zero.

Three-phase four-wire has no load, two-phase voltage is high, and one phase is low.

Three-phase four-wire has no load, two-phase voltage is high and one phase is low, three-phase four-wire two-phase voltage is high and one phase is low, which may be a serious imbalance of three-phase load. Three-phase four-wire power supply system with three live wires and one neutral wire. The voltage between the three live wires is a line voltage of 380 volts.

Between the three live wires and the neutral wire is a phase voltage of 220 volts. If the three-phase load is balanced, the neutral point potential on the load side is zero. When the three-phase load is seriously unbalanced, the three-phase potential displacement is large, which changes the phase voltage of each live wire.

There is no load, or one phase is low, two phases are high, what is the reason.

Hello dear, the three-phase four-wire two-phase voltage is high and the one-phase voltage is low, which may be a serious imbalance of the three-phase load. Three-phase four-wire power supply system with three live wires and one neutral wire. The voltage between the three live wires is a line voltage of 380 volts.

Between the three live wires and the neutral wire is a phase voltage of 220 volts. If the three-phase load is balanced, the neutral point potential on the load side is zero. When the three-phase load is seriously unbalanced, the three-phase potential displacement is large, which changes the phase voltage of each live wire.

A phase with a particularly heavy load will have a low phase voltage.

The phase voltage and line voltage of the three-phase four-wire system are high, and there are many reasons for this problem. Generally speaking, if there is no fault in the system, then the first thing you should check is to check the voltage of the system. For example, if the high-voltage side is 10000V, then its voltage will increase, and on the low-voltage side, the measured voltage will naturally increase.

There is also a possibility that the tap changer gear of the transformer is not adjusted well, resulting in the voltage attack section on the low voltage side of the transformer being too high, and the tap switch gear needs to be adjusted. Also, double-check the neutral point of the transformer. A problem with the neutral point of the transformer, or a broken neutral line, will cause the voltage to rise.

The neutral line in the three-phase four-wire system is without electricity, and the neutral line in the single-phase electricity in household is electric. The power supply of three-phase four-wire power supply has only three live wires and one neutral wire, this neutral wire is the integration of the neutral line and the ground wire, and this neutral wire is drawn out by the secondary neutral point of the transformer, and the secondary neutral point is connected with the zero potential of the earth, and the three live wires form a loop; So under normal circumstances, the zero line of the three-phase four-wire system is without electricity.

The single-phase electricity commonly used in the home is a circuit composed of a live wire and a neutral wire, and the third is a ground wire, which is a protective wire to prevent electric shock; The zero line in this circuit is called the working zero line, and the working zero line is live, but we can't measure it when measuring with an electrical measuring instrument, the reason is that one end of the zero line is drawn from the neutral point of the power supply, and the potential difference to the ground is zero.

The neutral line without arbitrary interruption will always be scattered and will not be electrified. Because the neutral line is the low voltage corresponding to the phase line, it has the same potential as the human body standing on the ground. But thousands of empty can not be dug jujube is cut off and suspended in the air, resulting in dangerous hidden dangers!

Summary. Hello, I am glad to answer for you: when the three-phase four-wire connection 220V, the voltage will drop to a certain extent, which is due to the fact that when 220V is connected, the load will form a certain impedance in the circuit, so that the original 220V voltage will drop to a certain extent.

At the same time, it will also be affected by the load, that is, the larger the load, the lower the voltage, and conversely, the smaller the load, the higher the voltage. Therefore, after the three-phase four-wire connection is 220V, if the load is large, the voltage will be relatively low, and conversely, if the load is small, the voltage will be relatively high.

Hello, I am glad to answer for you: when the three spring phase four wires are connected to 220V, the voltage will drop to a certain extent, which is due to the fact that when the 220V is connected, the load will form a certain impedance in the circuit, and the original 220V voltage will drop to a certain extent. At the same time, it will also be affected by the load, that is, the larger the load, the lower the voltage of Yusen ridge, and conversely, the smaller the load, the higher the voltage.

Therefore, after the three-phase four-wire connection is 220V, if the load is large, the voltage will be relatively low, and conversely, if the load is small, the voltage will be relatively high.

After the zero line is burned out due to the excessive load of 220V, the voltage of the tail section is normal at 220V after maintenance, and the voltage drops to about 100 after the load (rice cooker).

Whether it is a neutral line issue.

There are many reasons for this.

The reasons may be as follows:1The power cord or terminal connector may have poor contact and excessive contact resistance, resulting in a drop in voltage under load; 2.

It may be that the simple source voltage of the household electricity is unstable, and the voltage drops under load; 3.It may be that the leakage protector (circuit breaker) is set too low, and the voltage under load is unstable; 4.It may be that the load loss is too large, and the voltage is unstable under load; 5.

It may be that the rated voltage of household appliances does not match the actual voltage, resulting in unstable voltage under load; 6.It may be that the capacitor parameters of household appliances are unqualified, and the voltage drops under load; 7.It may be that the wiring of household appliances is not set properly, and the voltage is unstable under load.

Due to the excessive power of 220, the zero line is burned out.

If this is not the case before the repair, it may indeed be neutral or the voltage is unstable.

Repair to 220 voltage rises to 400V

You need to find someone to come and fix it again.

I just can't find a problem.

This must be the best line is not connected.

You must not have done this before you burned it.

No. If the repair is as it was before, it will definitely be fine.

So it must be the time for repair** not to get it right.

Otherwise, there would be no problem.

It's like repairing a mobile phone.

If the phone is repaired, it is completely fine, and it will be found after a while if it is not repaired.

The suggestion is to see if there is still a problem with the repair.