How to connect a three-phase motor to 220 volts. How to choose a capacitor for a three-phase motor in a single-phase network

Must be connected to home network to 220 V. Since the engine will not start, it is necessary to change some details in it. This can be easily done on your own. Even though the efficiency will decrease somewhat, this approach is justified.

Three-phase and single-phase motors

To figure out how to connect an electric motor from 380 to find out what 380 volt power means.

Three-phase motors have many advantages over household single-phase motors. Therefore, their application in industry is extensive. And the point is not only in power, but also in the coefficient useful action. They also provide starting windings and capacitors. This simplifies the design of the mechanism. For example, the starting protective relay of the refrigerator monitors how many windings are connected. And in a three-phase motor, this element is no longer necessary.

This is achieved by three phases, during which an electromagnetic field rotates inside the stator.

Why 380 V?

When the field inside the stator rotates, the rotor also moves. The turns do not match the 50 Hertz of the network due to the fact that there are more windings, the number of poles is different, and slippage occurs for various reasons. These indicators are used to regulate the rotation of the motor shaft.

All three phases have a value of 220 V. However, the difference between any two of them at any time will be different from 220. This will turn out to be 380 Volts. That is, the engine is used for operation, while there is a phase shift of one hundred and twenty degrees.

Because it is impossible to connect a 380 to 220 Volt electric motor directly, you have to use tricks. The capacitor is considered the most in a simple way. When the capacitance passes the phase, the latter changes by ninety degrees. Although it does not reach one hundred and twenty, this is enough to start and operate a three-phase motor.

How to connect an electric motor from 380 to 220 V

To implement the task, it is necessary to understand how the windings are arranged. Usually the case is protected by a casing, and wiring is located under it. After removing it, you need to examine the contents. You can often find a wiring diagram here. In order for the network 380-220 to take place, switching in the form of a star is used. The ends of the windings are at a common point, which is called neutral. Phases are fed to the opposite side.

"Star" will have to change. To do this, the motor windings must be connected in a different shape - in the form of a triangle, combining them at the ends with each other.

How to connect an electric motor from 380 to 220: diagrams

The schema might look like this:

• mains voltage is applied to the third winding;
• then the voltage will pass to the first winding through the capacitor with a phase shift of ninety degrees;
• the voltage difference will affect the second winding.

It is clear that the phase shift will be ninety and forty-five degrees. Because of this, the rotation will not be uniform. In addition, the phase shape on the second winding will not be sinusoidal. Therefore, after it is possible to connect a three-phase electric motor to 220 volts, it will not be able to be implemented without power loss. Sometimes the shaft even sticks and stops spinning.

Working capacity

After a set of revolutions, the starting capacity will no longer be needed, since the resistance to movement will become insignificant. To discharge the capacitance, it is shortened by a resistance through which the current will no longer pass. For the correct choice of working and starting capacity, first of all, it must be taken into account that the working capacitor voltage must significantly overlap 220 volts. It should be at least 400 V. You also need to pay attention to the wires so that the currents are intended for single-phase network.

If the working capacity is too low, the shaft will stick, so the initial acceleration is used for it.

Working capacity also depends on the following factors:

• The more powerful the motor, the more capacitor rating will be required. If the value is 250 W, then a few tens of microfarads will suffice. However, if the power is higher, then the denomination can be considered hundreds. It is better to buy film capacitors, because electric ones will have to be completed additionally (they are designed for direct, not alternating current, and can explode without alterations).
• The higher the engine speed, the higher the rating is needed. If we take the engine at 3000 rpm and a power of 2.2 kW, then it will need a battery from 200 to 250 microfarads. And this is of great importance.

This capacity also depends on the load.

Final stage

It is known that an electric motor of 380 V at 220 Volts will work better if the voltages are obtained with equal values. For this, the winding connected to the network does not need to be touched, but the potential is measured on both others.

The asynchronous motor has its own It is necessary to determine the minimum at which it will start rotating. After that, the value is gradually increased until all the windings are aligned.

But when the engine spins up, it may turn out that equality is violated. This is due to the reduction in resistance. Therefore, before connecting the electric motor from 380 to 220 Volts and fixing this, you need to equalize the values ​​\u200b\u200band with the unit running.

The voltage may be higher than 220 V. Look to ensure stable docking of the contacts, and there is no power loss or overheating. Switching is best done on special terminals with fixed bolts. After connecting the electric motor from 380 to 220 Volts, it turned out with the necessary parameters, the casing is again put on the unit, and the wires are passed through the rubber seal on the sides.

What else can happen and how to solve problems

Often, after assembly, it is found that the shaft rotates in the wrong direction. The direction needs to be changed.

To do this, the third winding is connected through a capacitor to the threaded terminal of the second stator winding.

It happens that due to long-term operation, engine noise appears over time. However, this sound is of a completely different kind compared to the hum when connected incorrectly. It happens over time and the vibration of the motor. Sometimes you even have to turn the rotor with force. This is usually caused by wear on the bearings, resulting in too large clearances and noise. Over time, this can lead to jamming, and later to damage to engine parts.

It is better not to allow this, otherwise the mechanism will become unusable. It is easier to replace the bearings with new ones. Then the electric motor will last for many more years.

Homegrown "kulibins" use whatever comes to hand for electromechanical crafts. When choosing an electric motor, three-phase asynchronous ones usually come across. This type has become widespread due to its successful design, good balance and economy.

This is especially true in powerful industrial units. Outside a private house or apartment, there are no problems with three-phase power. And how to organize the connection of a three-phase motor to a single-phase network if your meter has two wires?

Consider the option of regular connection

Three-phase motor, has three windings at an angle of 120°. Three pairs of contacts are displayed on the contact block. The connection can be established in two ways:

Connection according to the scheme "star" and "delta"

Each winding is connected at one end to two other windings, forming the so-called neutral. The remaining ends are connected to three phases. Thus, 380 volts are supplied to each pair of windings:

In the distribution block, the jumpers are connected accordingly, it is impossible to mix up the contacts. There is no concept of polarity in alternating current, therefore it does not matter which phase, which wire to apply.

With this method, the end of each winding is connected to the next, resulting in a vicious circle, more precisely a triangle. Each winding has a voltage of 380 volts.

Wiring diagram:

Accordingly, jumpers are installed differently on the terminal block. Similarly with the first option, there is no polarity as a class.

For each group of contacts, current flows at a different time, following the concept of "phase shift". Therefore, the magnetic field consistently drags the rotor along with it, creating a continuous torque. This is how the engine works with its “native” three-phase power supply.

And if you got an engine in excellent condition, and you need to connect it to a single-phase network? Do not be upset, the connection diagram of a three-phase motor has long been worked out by engineers. We will share with you the secrets of several popular options.

Connecting a three-phase motor to a 220 volt network (single phase)

At first glance, the operation of a three-phase motor when connected to one phase is no different from correct inclusion. The rotor rotates, practically without losing speed, no jerks and slowdowns are observed.

However, it is impossible to achieve nominal power with such a power supply. This is a forced loss, there is no way to fix it, you have to reckon with it. Depending on the control circuit, the power reduction ranges from 20% to 50%.

In this case, electricity is consumed in the same way as if you were using all the power. To choose the most profitable option Let's take a look at the different ways:

Capacitive switching method

Since we need to provide the same “phase shift”, we use the natural abilities of capacitors. We have two lead wires, we connect them respectively to both points of the standard terminal block.

There remains a third contact, which receives current from one of the already connected ones. And not directly (otherwise the engine will not start rotating), but through a capacitor circuit.
Two capacitors are used (they are called phase-shifting).

The above diagram shows that one capacitor is constantly on, and the second through a non-fixed button. The first element is working, its task is to simulate a regular phase shift for the third winding.

The second container is intended for the first revolution of the rotor, then it spins by inertia, each time falling between false "phases". The start capacitor should not be left on all the time, as it will confuse the relatively smooth rotational rhythm.

note

The above diagram for connecting a three-phase motor to a single-phase network is theoretical. For real work it is necessary to correctly calculate the capacitances of both elements, and select the type of capacitors.

The formula for calculating the working "capacitor":

• When connected with a "star" C \u003d (2800 * I) / U;
• When connected with a "triangle" C \u003d (4800 * I) / U;

Single-phase motor runs on AC electric current and connects to networks with one phase. The network must have a voltage of 220 volts and a frequency of 50 hertz.

Electric motors of this type are used mainly in low-power devices:

1. Household appliances.
2. Fans low power.
3. pumps.
4. machine tools for processing raw materials, etc.

Models with power from 5 W to 10 kW are produced.

The values ​​of efficiency, power and starting torque for single-phase motors are significantly lower than for three-phase devices of the same size. The overload capacity is also higher for 3-phase motors. So, the power of a single-phase mechanism does not exceed 70% of the power of a three-phase mechanism of the same size.

device

Device:

1. Actually has 2 phases, but only one of them does the work, so the motor is called single-phase.
2. Like all electric machines, a single-phase motor consists of 2 parts: fixed (stator) and movable (rotor).
3. Represents, on the fixed component of which there is one working winding connected to a single-phase alternating current source.

To strengths engine of this type can be attributed to the simplicity of the design, which is a rotor with a short-circuited winding. The disadvantages are low starting torque and efficiency.

The main disadvantage of single-phase current- the impossibility of generating a magnetic field that performs rotation. Therefore, a single-phase electric motor will not start by itself when connected to the network.

In the theory of electrical machines, the rule applies: in order for a magnetic field to turn the rotor, there must be at least 2 windings (phases) on the stator. It is also required to shift one winding at a certain angle relative to the other.

During operation, alternating electric fields flow around the windings:

1. According to this, on a fixed section of a single-phase motor is the so-called starting winding. It is offset by 90 degrees with respect to the working winding.
2. Shift currents can be obtained by including a phase-shifting link in the circuit. Active resistors, inductors and capacitors can be used for this.
3. As a basis 2212 electrical steel is used for the stator and rotor.

It is incorrect to call single-phase electric motors that are 2- and 3-phase in their structure, but are connected to a single-phase power source through matching circuits (capacitor electric motors). Both phases of such devices are operational and are on all the time.

Principle of operation and launch scheme

Principle of operation:

1. electric shock a pulsating magnetic field is generated on the motor stator. This field can be considered as 2 different fields that rotate in different directions and have equal amplitudes and frequencies.
2. When the rotor is stationary, these fields lead to the appearance of equal in absolute value, but oppositely directed moments.
3. If the engine does not have special starting mechanisms, then at the start the resulting torque will be equal to zero, which means that the engine will not rotate.
4. If the rotor is rotated in one direction, then the corresponding moment begins to prevail, which means that the motor shaft will continue to rotate in a given direction.

Launch scheme:

1. Launched by magnetic field, which rotates the moving part of the motor. It is created by 2 windings: main and additional. The latter has smaller size and is the launcher. It connects to the main electrical network through capacitance or inductance. The connection is made only during start-up. In low power motors, the starting phase is short-circuited.
2. Engine start carry out withholding start button for a few seconds, resulting in acceleration of the rotor.
3. When the start button is released, the electric motor passes from the two-phase mode to the single-phase one, and its operation is supported by the corresponding component of the alternating magnetic field.
4. Starting phase designed for short-term operation - usually up to 3 s. A longer time under load can lead to overheating, insulation fire and mechanism failure. Therefore, it is important to release the start button in a timely manner.
5. In order to improve reliability a centrifugal switch and a thermal relay are built into the housing of single-phase motors.
6. Centrifugal switch function consists in turning off the starting phase when the rotor is gaining rated speed. This happens automatically - without user intervention.
7. Thermal relay turns off both phases of the winding if they heat up above the permissible level.

Connection

The device requires 1 phase with a voltage of 220 volts. This means that you can plug it into a household outlet. This is the reason for the popularity of the engine among the population. For everyone household appliances, from a juicer to a grinder, mechanisms of this type are installed.

connection with start and run capacitors

There are 2 types of electric motors: with a starting winding and with a running capacitor:

1. In the first type of devices, the starting winding works by means of a capacitor only during the start. After the machine reaches normal speed, it turns off and work continues with one winding.
2. In the second case, for motors with a running capacitor, the additional winding is permanently connected through the capacitor.

The electric motor can be taken from one device and connected to another. For example, a serviceable single-phase motor from washing machine or a vacuum cleaner can be used to operate a lawn mower, cutting machine, etc.

There are 3 schemes for switching on a single-phase motor:

1. In 1 scheme, the work of the starting winding is carried out by means of a capacitor and only for the starting period.
2. 2 scheme also provides for a short-term connection, however, it occurs through a resistance, and not through a capacitor.
3. 3 scheme is the most common. In this scheme, the capacitor is constantly connected to the source of electricity, and not just during the start.

Connecting an electric motor with starting resistance:

1. Auxiliary winding such devices has an increased active resistance.
2. To start the electric machine of this type, a starting resistor can be used. It should be connected in series with the starting winding. Thus, it is possible to obtain a phase shift of 30 ° between the winding currents, which will be quite enough to start the mechanism.
3. Besides, phase shift can be obtained by using a starting phase with a higher resistance value and lower inductance. Such a winding has fewer turns and a thinner wire.

Connecting a motor with capacitor start:

1. For these electric machines the starting circuit contains a capacitor and is switched on only for the start period.
2. To reach the maximum value starting torque, a circular magnetic field is required, which performs rotation. For it to occur, the winding currents must be rotated 90° relative to each other. Phase-shifting elements such as a resistor and a choke do not provide the necessary phase shift. Only the inclusion of a capacitor in the circuit allows you to get a phase shift of 90 °, if you choose the right capacitance.
3. Calculate which wires belong to which winding can be done by measuring the resistance. For the working winding, its value is always less (about 12 ohms) than for the starting winding (usually about 30 ohms). Accordingly, the cross section of the wire of the working winding is larger than that of the starting one.
4. Capacitor selected according to the current consumed by the motor. For example, if the current is 1.4 A, then a 6 uF capacitor is needed.

Health check

How to check engine performance by visual inspection?

The following are the defects that indicate possible problems with the engine, they could be caused by incorrect operation or overload:

1. broken prop or mounting slots.
2. In the middle of the motor darkened paint (indicates overheating).
3. Through the cracks external substances are drawn into the device in the housing.

To check the performance of the engine, you should first turn it on for 1 minute, and then let it run for about 15 minutes.

If after that the engine is hot, then:

1. maybe bearings are dirty, pinched, or simply worn out.
2. Cause may be in too high a capacitance of the capacitor.

Disconnect the capacitor and start the motor manually: if it stops heating up, it is necessary to reduce the capacitor capacitance.

Model overview

electric motor AIR

One of the most popular are electric motors of the AIR series. There are models made on legs 1081, and models of combined execution - legs + flange 2081.

Foot+flange motors will cost approximately 5% more than foot-mounted motors.

As a rule, manufacturers provide a guarantee of 12 months.

For electric motors with a rotation height of 56-80 mm, the frame is made of aluminum. Motors with a rotation height of more than 90 mm are available in cast iron.

Models differ from each other in terms of power, rotational speed, height of the axis of rotation, efficiency.

The more powerful the engine, the higher its cost:

1. 0.18 kW motor can be purchased for 3 thousand rubles (AIRE 56 B2 electric motor).
2. 3 kW model will cost about 10 thousand rubles (AIRE 90 LB2).

As for the speed, the most common models with frequencies of 1500 and 3000 rpm, although there are engines with other speeds. At equal powers, the cost of a 1500 rpm motor is slightly higher than that of a 3000 rpm motor.

The height of the axis of rotation for motors with 1 phase varies from 56 mm to 90 mm and directly depends on the power: the more powerful the engine, the greater the height of the axis of rotation, and hence the price.

Different models have different efficiency, usually between 67% and 75%. Greater efficiency corresponds to a greater cost of the model.

You should also pay attention to the engines manufactured by the Italian company AASO, founded in 1982:

1. So, the electric motor AASO series 53, designed specifically for use in gas burners. These motors can also be used in washing machines, generators warm air, centralized heating systems.
2. Electric motors series 60, 63, 71 designed for use in water supply installations. Also, the company offers universal motors of the 110 and 110 compact series, which are distinguished by a variety of applications: burners, fans, pumps, lifting devices and other equipment.

You can buy motors manufactured by AASO at a price of 4600 rubles.

It happens that a three-phase electric motor falls into the hands. It is from such engines that home-made circular saws, emery machines and various kinds of grinders are made. In general, a good owner knows what can be done with him. But the trouble is, a three-phase network in private homes is very rare, and it is not always possible to conduct it. But there are several ways to connect such a motor to a 220v network.

It should be understood that the engine power with such a connection, no matter how hard you try, will noticeably drop. So, the “triangle” connection uses only 70% of the engine power, and the “star” connection is even less - only 50%.

In this regard, the engine is desirable to have more powerful.

Important! When connecting the engine, be extremely careful. Do everything slowly. When changing the circuit, turn off the power supply and discharge the capacitor with an electric lamp. Do the work with at least two people.

So, in any connection scheme, capacitors are used. In fact, they play the role of the third phase. Thanks to him, the phase to which one terminal of the capacitor is connected shifts exactly as much as is necessary to simulate the third phase. Moreover, for the operation of the engine, one capacity (working) is used, and for starting, another one (starting) is used in parallel with the working one. Although this is not always necessary.

For example, for a lawn mower with a blade in the form of a sharpened blade, a 1 kW unit and only working capacitors will be enough, without the need for start-up tanks. This is due to the fact that the engine is idling at startup and it has enough energy to spin the shaft.

If you take a circular saw, hood or other device that gives the initial load on the shaft, then you can’t do without additional cans of capacitors to start. Someone may say: “why not connect the maximum capacity so that there is not enough?” But not everything is so simple. With this connection, the motor will overheat and may fail. Don't risk your equipment.

Important! Whatever the capacity of the capacitors, their operating voltage must be at least 400V, in otherwise they will not last long and may explode.

Let's first consider how a three-phase motor is connected to a 380v network.

Three-phase motors come in both with three leads - for connecting only to a "star", and with six connections, with the choice of a star or delta circuit. classical scheme can be seen in the figure. The figure on the left here shows a star connection. The photo on the right shows how it looks on a real motor brand.

It can be seen that for this it is necessary to install special jumpers on the desired outputs. These jumpers are included with the motor. In the case when there are only 3 outputs, then the star connection is already made inside the motor housing. In this case, it is simply impossible to change the connection scheme of the windings.

Some say that they did this so that the workers would not steal the units from home for their own needs. Be that as it may, such engine options can be successfully used for garage purposes, but their power will be noticeably lower than those connected by a triangle.

Scheme of connecting a 3-phase motor to a 220v network connected by a star.

As you can see, the voltage of 220V is distributed into two series-connected windings, where each is designed for such a voltage. Therefore, power is lost almost twice, but such an engine can be used in many low-power devices.

The maximum power of a 380v motor in a 220v network can only be achieved using a delta connection. In addition to minimal power losses, the engine speed remains unchanged. Here, each winding is used for its operating voltage, hence the power. The connection diagram of such an electric motor is shown in Figure 1.

In Fig. 2, a brno is shown with a 6-pin terminal for the possibility of connecting with a triangle. The three resulting outputs are supplied: phase, zero and one output of the capacitor. The direction of rotation of the electric motor depends on where the second output of the capacitor is connected - phase or zero.

In the photo: an electric motor with only working capacitors without start-up tanks.

If there will be an initial load on the shaft, capacitors must be used to start. They are connected in parallel with the workers using a button or switch at the time of switching on. As soon as the engine reaches maximum speed, the start containers must be disconnected from the workers. If it's a button, just release it, and if it's a switch, then turn it off. Further, the engine uses only the working capacitors. Such a connection is shown in the photo.

How to choose capacitors for a three-phase motor using it in a 220v network.

The first thing to know is that capacitors must be non-polar, that is, not electrolytic. It is best to use brand containers - MBGO. They were successfully used in the USSR and in our time. They perfectly withstand voltage, current surges and the damaging effects of the environment.

They also have eyelets for mounting, helping to easily place them anywhere in the body of the device. Unfortunately, it is problematic to get them now, but there are many other modern capacitors that are no worse than the first ones. The main thing is that, as mentioned above, their operating voltage should not be less than 400V.

Calculation of capacitors. Capacitance of the working capacitor.

In order not to resort to long formulas and torture your brain, there is an easy way to calculate a capacitor for a 380v motor. For every 100 W (0.1 kW), 7 microfarads are taken. For example, if the engine is 1 kW, then we calculate as follows: 7 * 10 \u003d 70 microfarads. It is extremely difficult to find such a capacity in one bank, and it is also expensive. Therefore, most often the containers are connected in parallel, gaining the desired capacity.

starting capacitor capacity.

This value is taken from the calculation of 2-3 times more than the capacity of the working capacitor. It should be borne in mind that this capacitance is taken in total with the working one, that is, for a 1 kW engine, the working one is equal to 70 microfarads, we multiply it by 2 or 3, and we get the required value. This is 70-140 microfarads of additional capacitance - starting. At the moment of switching on, it is connected to the working one and in total it turns out - 140-210 microfarads.

Features of the selection of capacitors.

Capacitors, both working and starting, can be selected by the method from smaller to larger. So, having selected an average capacity, you can gradually add and monitor the engine's operating mode so that it does not overheat and has enough power on the shaft. Also, the starting capacitor is selected by adding until it starts smoothly without delay.

One of the reasons for connecting a three-phase motor to a single-phase circuit is that the supply of electrical energy to industrial facilities and for domestic needs is fundamentally different.

For industrial production, electrical enterprises manufacture electric motors with a three-phase power system, and to start the engine, you need to have 3 phases.

What to do if you purchased motors for industrial production, but you need to connect to home socket? Some skillful specialists, with the help of simple electrical circuits, adapt the electric motor to a single-phase network.

Winding connection diagram

To understand a person who first encountered a similar problem, you need to know how a three-phase motor works. If you open the connection cover, you can see the block and the wires attached to the terminals, their number will be 6.

A three-phase electric motor has three windings and 6 leads, respectively, they have a beginning and an end, and are connected in electrical configurations called star and delta.

This is interesting, but in most cases, standard switching is formed into a "star", since the connection to the "delta" leads to a loss of power, but an increase in engine speed. It happens that the wires are in an arbitrary position and are not connected to the connectors or there is no terminal at all. In this case, you must use the device tester or ohmmeter.

You need to ring each wire and find a pair, these will be the three motor windings. Next, we connect it into a “star” configuration as follows: start-end-start. We clamp three wires under one terminal. There should be three outputs left, and further switching will take place to them.

It's important to know: a single-phase power supply system or “phase and zero” is organized in a household network. This configuration must be used to connect the motor. From the beginning, we connect one wire from the electric motor to any wire of the network, then, to the second end of the winding, we connect the network wire and one end of the capacitor unit there.

The last wire from the engine and the unconnected contact of the capacitor set remain free, we connect them and the circuit for starting a three-phase motor into a single-phase network is ready. Graphically, they can be represented as follows:

• A, B, C - lines of a 3-phase circuit.
• F and O - phase and zero.
• C is a capacitor.

In industrial production, a 3-phase voltage supply system is used. According to the PUE standards, all network buses are marked with letter values ​​and have the corresponding color:

A is yellow.

B is green.

C is red.

It is noteworthy that, regardless of the arrangement of the phases, in, bus "B", with in green should always be in the middle. Attention! The interfacial voltage is measured by a special device that has passed the state check and is a worker with the appropriate tolerance group. Ideally, the phase-to-phase voltage is -380 volts.

Motor device

Most often, electric motors with a three-phase asynchronous operation scheme fall into our hands. What is an engine? This is a shaft on which a squirrel-cage rotor is pressed in, on the edges of which there are plain bearings.

The stator is made of transformer steel, with high magnetic permeability, cylindrical shape with longitudinal grooves for laying the wire and a surface insulating layer.

According to a special technology, the winding wires are laid in the stator channels and isolated from the housing. The symbiosis of the stator and rotor is called an asynchronous type electric motor.

How to calculate the capacitance of a capacitor

To start a 3-phase motor from a household network, it is necessary to perform some manipulations with the capacitor units. To start the electric motor without a "load", you need to select the capacitance of the capacitor based on the formula 7-10 mF per 100 W of motor power.

If you look closely at the side of the electric motor, you will find its passport, where the power of the unit is indicated. For example: if the engine has a power of 0.5 kW, then the capacitance of the capacitor should be 35 - 50 mF.

It should be noted that only “permanent” capacitors are used, in no case “electrolytic” ones. Pay attention to the inscriptions that are on the side of the case, they talk about the capacitance of the capacitor, measured in microfarads, and the voltage for which they are designed.

The block of starting capacitors is assembled according to this formula. Using the engine as a power unit: connect it to a water pump or use it as a circular saw, an additional capacitor bank is required. This design is called - the working blocks of capacitors.

They start the engine and, by connecting in series or in parallel, select the capacitance of the capacitor so that the sound from the electric motor comes from the quietest, but there is a more accurate method of selecting the capacitance.

For a verified selection of a capacitor, it is necessary to have a device called a container store. Experimenting with different connection combinations, they achieve the same voltage value between all three windings. Then the capacitance is read and the desired capacitor is selected.

Necessary materials

In the process of connecting a 3-phase motor to a single-phase network, some materials and devices will be needed:

• A set of capacitors with different ratings or "capacity store".
• Electrical wires, type PV-2.5.
• Voltmeter or tester.
• 3 position switch.

Basic tools should be at hand: voltage indicator, dielectric pliers, insulating tape, fasteners.

Parallel and series connection of capacitors

The capacitor belongs to electronic parts and with different switching combinations, its nominal values ​​\u200b\u200bmay change.

Parallel connection:

Serial connection:

It should be noted that when capacitors are connected in parallel, the capacitances will add up, but the voltage will decrease, and vice versa, the series version gives an increase in voltage and a decrease in capacitance.

In conclusion, we can say that there are no hopeless situations, you just need to make a little effort and the result will not be long in coming. Electrical engineering is a cognitive and useful science.

How to connect a three-phase motor to a single-phase network, see the instructions in the following video: