How to connect three phase electricity?

Three-phase alternating current is a form of transmission of electrical energy, referred to as three-phase electricity. Three-phase AC power supply is a power supply composed of three alternating currents with the same frequency, equal amplitude, and 120° difference in phase. Three-phase alternating current has many uses, and most of the alternating current electrical equipment in the industry, such as motors, use three-phase alternating current, which is often referred to as the three-phase four-wire system.

In daily life, single-phase power supply, also known as lighting electricity, is mostly used. When lighting electricity is used, one of the three phases is used to supply power to the consumer, such as household appliances, and the other wire is the fourth wire in the three-phase four-wire, that is, the neutral line, which leads from the neutral point of the three-phase electricity.

Three-phase electricity is divided into triangular connection (symbol) and star connection (also known as Y-shaped connection, symbol Y).

The load leads of the triangle connection are three live wires and one ground wire, the voltage between the three live wires is 380V, and the voltage of either live wire to ground wire is 220V;

The load leads of the Y-junction are three live wires, one neutral wire and one ground wire, and the voltage between the three live wires is 380V, and the voltage of either live wire to neutral or ground wire is 220V.

You can't pick it up like this.

1. You only have a two-phase load, you can't use a three-phase meter;

2. The current policy does not allow two families to share a meter.

3. Even if you pick up your home in violation of regulations, the billing of the two families will not be separated, and there will be endless skins.

4. After this connection, because the zero line is shared, there are serious safety hazards, which endanger life safety at any time.

You can't tell the difference between the two electricity bills when you use them like this. Each family installs a sub-meter under the three-phase meter, which is used separately, and the electricity bill is clearly divided.

The connection method of three-phase electricity is: three-phase electricity has two connection methods of star and triangle at the power supply end (or transformer) and load end.

The star connection of three-phase electricity is to connect one end of each phase power supply or load to one point, and the other end of them is used as a lead-out wire, which is the three phase wires of three-phase electricity. For the star connection, the midpoint (called the neutral point) can be drawn out as a neutral line, forming a three-phase four-wire system. It can also be drawn out without drawing out to form a three-phase three-wire system.

Of course, with or without a neutral wire, you can add a ground wire to become a three-phase five-wire system or a three-phase four-wire system, respectively.

The triangle connection of three-phase electricity is to connect each phase power supply or load end to end in turn, and lead each connected point out as the three phase wires of three-phase electricity. The triangular connection has no neutral point and cannot lead to a neutral line, so there is only a three-phase three-wire system. When the ground wire is added, it becomes a three-phase four-wire system.

In the three-phase electricity of the star connection, the line voltage is a multiple of the phase voltage, and the line current is equal to the phase current. When a three-phase load is balanced, no current flows over it, even if a neutral wire is connected. When the three-phase load is unbalanced, the neutral wire should be connected, otherwise the load of each phase will be unequal.

What is three-phase electricity.

Three-phase power supply is generally what people call power electricity, which is 380 volts alternating current, composed of three live wires, without zero wire, and is generally used for electricity consumption in factories and enterprises. Any combination of live and neutral wires of a three-phase power supply will constitute a single-phase power supply.

Single-phase power refers to the 220 volt alternating current used at home, that is, the mains power, which consists of a live wire and a neutral wire; Three-phase power supply is generally what people call power electricity, which is 380 volts alternating current, composed of three live wires, without zero wire, and is generally used for electricity consumption in factories and enterprises. Any combination of live and neutral wires of a three-phase power supply will constitute a single-phase power supply.

Difference Between Three-Phase Electricity and Two-Phase Electricity.

The difference between three-phase power supply and two-phase power supply: the power supply sent by the generator is three-phase, and each phase of the three-phase power supply and its neutral point can form a single-phase circuit to provide users with power energy. Note that it cannot be called the positive or negative electrode in the AC circuit here, but should be called the line end (called the live wire in civil electricity) and the neutral wire (called the neutral line in civil electricity).

1: The star connection method means that one end of each phase power supply is connected to one point, and the other end is used as a lead, which is used as a phase wire in the three-phase electricity, and the midpoint is drawn out as a neutral wire to form a three-phase four-wire system;

2: The triangle connection method is to connect the power supply of each phase in order from end to end, and at the same time lead out the connected points for three-phase electricity, without the need for a neutral point or a neutral line.

Three-phase motors have two wiring modes of operation:

1. Star (Y) connection, suitable for three-phase asynchronous induction motors of 3 kilowatts and below.

1. The first or last end of the three-phase stator winding inside the motor is connected.

2. The other end of the three-phase is respectively connected to the three-phase alternating current operation.

1. The head and tail of the three-phase stator winding are correspondingly connected, the first end of the first phase winding and the tail end of the third phase winding can be regarded as U phase, the first end of the second winding and the tail end of the first winding can be connected to the V phase, and the first end of the third winding and the tail end of the second winding can be connected to the W phase, which is respectively connected to the three-phase AC power supply.

There are two connections for three-phase electric motors, namely one is the triangle wiring method and the other is the star wiring method.

There are many kinds of connection methods for three-phase electricity, including TT system, TN system and IT system, and there are different connections according to different needs!

Three-phase electricity has two connections: star and triangle at the power supply end (or transformer) and load side.

The star connection method of three-phase electricity is to connect both ends of each phase power supply or load at one point, and the other end of them is used as a lead-out wire, and there are three phase wires of three-phase electricity. For the star junction method, the midpoint (called the neutral point) can be drawn out as a neutral line to form a three-phase four-wire system. It is also not necessary to draw out and form a three-phase three-wire system.

Of course, regardless of whether there is a neutral wire or not, it can be added to the ground wire and become a three-phase five-wire system or a three-phase four-wire system, respectively.

The triangular connection of three-phase electricity is to connect each phase power supply or load in order end-to-end, and lead out each connected point as the three phase wires of three-phase electricity. The triangle connection has no neutral point and cannot lead to a neutral line, so there is only a three-phase three-wire system. When added to the ground wire, it becomes a three-phase four-wire system.

In the three-phase electricity of the star connection, the line voltage is a multiple of the phase voltage, and the line current is equal to the phase current. When a three-phase load is balanced, no current flows to the neutral wire, even if it is connected. When the three-phase load is unbalanced, the neutral wire should be connected, otherwise the load of each phase will be unequal.

Ask friends: three-phase electricity is three live wires and a zero wire, if you want to connect two-phase electricity to use, generally connect a live wire and a zero wire can be used, note, do not connect into two live wires, then the electrical appliances will be burned immediately.

Hello, I have seen your question and am sorting out the answer, please wait for a while Hello, I have seen your question and am sorting out the answer, please wait a while Hello! 1.The color of the three-phase electricity is yellow in phase A, green in phase B, and red in phase C.

There are several names: a, b, c or l1, l2, l3 or u, v, w, all in the same order. 2.

Evenly distribute the three-phase electricity to the six upper ends of the empty opening.

Hello! Do you have any other questions that can help you If I help you, there are no other questions, I hope you can give a like, thank you very much

Firewire connects any one of the three. The neutral line must be connected to the neutral wire.

Only the old-fashioned AC welding machine is connected to two live wires, and any other electrical appliance is one live wire and one 0 wire.

"Let's talk about the distinction of three-phase electricity first: three-phase three-wire, from left to right, from top to bottom, from inside to outside, the order is yellow-green-red, or ABC or L1L2L3 or UVW, three-phase four-wire also has an N line (zero line), in the front or last, blue or black. Three-phase electricity connection:

Three-phase electricity has three-phase three-wire and three-phase four-wire connection, the usual three-phase electric equipment, as long as the three-phase three-wire connection, the principle of three-phase electricity is: the time electric phase difference of each phase.

When connecting 3-phase electrical equipment, it is necessary to pay attention to distinguish the phase sequence of 3 phases, a, b, c, and color code (for a, b, c, is yellow, green, red and red) for equipment with high requirements, if there is no phase sequence protection will cause losses, 3-phase electricity must be connected firmly because it must not lack phase, and can not cause losses to users.

As long as the zero line of the three-phase four-wire air conditioner is not connected wrong, and the three-phase electricity is reversed, the air conditioner will not be reversed, and there will be no consequences, as long as the phase sequence is changed, the three-phase air conditioner has reverse phase loss protection, so don't worry.

The voltage between each two phases of the three-phase electricity is 380V, and the bulb is 220V, which will definitely burn. The color scale of the three-phase line is yellow for phase A, green for phase B, red for phase C, light blue for the neutral wire (i.e. zero line), and yellow and green for the protective neutral (ground wire). The voltage between the phase line and the neutral line is 220V.

(1) 3 identical points connected to the live wire, the larger zero wire, if there is any grounding, connect a grounding wire outside the socket. (2) 3 identical points to the live wire, the larger ground.

The three-phase electrically connected two-phase method is as follows:

1. The color of three-phase electricity is yellow, B is green, and C is red, and there are currently the following names: A, B, C or L1, L2, L3 or U, V, W, the order is the same.

2. Evenly distribute the three-phase electricity to the upper end of the six empty openings. The specific method is: the three-phase electricity under the empty switch from left to right is respectively; The first two-phase empty opening upper end is connected to 1 and 2 respectively;

3, the second two-phase empty opening upper end is connected to 2 and 3 respectively; The upper end of the third two-phase empty opening is connected to 3 and 1 respectively; Then, the fourth empty opening is the same as the first empty opening method; The fifth air opening and the second air opening method are the same; The same is true for the sixth and third space openings. In this way, the three phases under the three-phase empty open are evenly distributed.

In the star connection, the line voltage is 3 times the phase voltage, and the line current is equal to the phase current. In the triangle connection, the line voltage is equal to the phase voltage, and the line current is 3 times the phase current.

According to the vector formula, the line voltage UAB = UA - UBN = UA (UA = UA, UBN = UB), it is obvious that the amplitude of the line voltage UAB is 3 times that of the phase voltage UA or UB.

Star connection of three-phase electricity

It is to connect one end of the three-phase power winding or load together to form a neutral wire, because the current in the neutral wire of the balanced three-phase electricity is zero, so it is also called the zero line: the lead wire at the other end of the three-phase power winding or load is the three phase wires of the three-phase electricity respectively.

In the case of long-distance power transmission, only three phase wires are used, forming a three-phase three-wire lead-resistant system. The circuit that reaches the user often involves two voltages, 220V and 380V, and requires three phase wires and one neutral wire to form a three-phase four-wire system.

In order to avoid the electric shock accident caused by leakage, the user also needs to add a ground wire, at this time there are three phase wires, a zero line and a ground wire, so there is also a three-phase mu trembling five-wire system.

Three-phase voltage is the voltage between phases, there are many kinds of voltage standards in various countries in the world, three-phase voltage 220V is one, three-phase 380V is another, and there are other voltages; In addition, the frequencies are also available in 50Hz and 60Hz. China's three-phase voltage standard is 380V, and the frequency between each phase is the same, and the frequency is 50Hz. Due to the use of star connection for residents to connect electricity in the middle, so if China says three-phase 380V, it refers to the line voltage, and the phase voltage is 220V; If we say three-phase 220V, it refers to the linear voltage, and its phase voltage is 127V.

Taiwan and other places are such power sources. Japan is a special case in the world, the east and west of Japan are different power grids, the phase voltage is 120V 60Hz and 220V 50Hz respectively, and at the same time access to the triangular connection used by residential electricity, so in Japan said that the line voltage and phase voltage are equivalent.

The end of the three windings of the three-phase power supply, X, Y, and Z are connected together to become a common point O, and three end wires are drawn from the beginning A, B, and C, which is called "star connection" and "Y-shaped connection". Three-phase power supply is a system in which three sinusoidal power supplies with the same frequency, equal amplitude and 120° phase difference are connected in a certain way to supply power to the outside. There are two types of connection methods for three-phase power supply: Y-shaped and shaped.

The star connection and the triangle connection method both refer to the winding connection method of the motor itself, and the star connection method refers to the three-phase end of the motor winding together, and the three-phase head end is the power supply end; The triangular connection refers to connecting the three-phase winding brigade width to each other, and the end of the three-phase land is the power supply end; No matter what kind of connection, there must be a three-phase sinusoidal AC power supply with a three-phase phase difference of 120 degrees, which cannot be replaced by 220V. Because the three-phase live wire (a, b, c) of three-phase alternating current is 220V, the phase difference between them is 120 degrees, and the voltage difference between the three phases is 380V, so it cannot be replaced by three live wires of the same phase.

Due to the small output power, the star connection method is often used for small power, large torque motors, or large power motors at the beginning, so that the loss of the machine is small, and the triangle connection method is used after normal operation;

Generally, the three-phase motor below 3kw is star-connected, and the above three-phase motor is used;

Triangular joints.

There is also a difference in voltage: the phase voltage output of the star connection and the triangle connection is 220V and 380V respectively.