Electric motor connection diagrams: single-phase and three-phase electric motors, the ability to connect

The principle of operation of any electric motor is the ability to transform electrical energy into mechanical energy. Regardless of the design, each electric machine is arranged in the same way: in the stationary part (stator or inductor), the moving part (rotor or armature) rotates. Correct connection of the electric motor is necessary for long-term trouble-free operation of the equipment.

Main varieties

Electric motors have a number of obvious advantages. They are much smaller in size than their thermal counterparts of identical power. Therefore, they are great for placement in public electric vehicles or on factory machines. During operation, they do not harm the environment by emitting decomposition products and vapor vapors.

Electric motors can be classified into two main groups:

1. DC motors. Suitable for variable speed drives with high quality performance such as readiness to reload and rotational uniformity. They are used to equip auxiliary units for excavators, polymer equipment, and drilling rigs. Electric motors are widely used in electric vehicles. DC / DC converters are additionally subdivided into collector and valve ones.
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2. AC motors. They are cheaper and more durable, with a simple and reliable design solution. The vast majority of household appliances are equipped with these electric motors. In industry, they are used in factory machines, fans, compressors, pumps, winches for lifting and moving loads. According to the principle of operation, these mechanisms are divided into synchronous and asynchronous.

Connection methods

Electric motors of any design have the same structure. In a static winding (stator), the rotor rotates. In it, a magnetic field is excited, repelling its poles from the stator. The smooth operation of this design is due to the correct connection of the electric motor, depending on the type used.

Single phase asynchronous

This motor got its name because it has only one working winding. Its power can range from five to ten kilowatts. The working and starting windings are located at right angles to each other.

A phase-shifting element must be connected to the circuit. Such a connection scheme for a single-phase electric motor with a capacitor has optimal starting properties. Using a capacitor, the electric motor can be equipped with the following types of this two-pole:

• workers;
• launcher;
• workers and launchers.

In practice, a starting capacitor is most often used. This option can be applied using a time relay or by closing the electrical circuit through the start button.

In the case of choosing a circuit for connecting a 220 V electric motor through a capacitor, the starting characteristics noticeably deteriorate. The third option with a starting and working two-pole is considered intermediate.

Collector option

The versatility of this motor lies in the fact that it has the ability to receive energy from converters of an alternating or constant type of current. It finds application in sewing or washing machines, household electrical tools.

Single-phase collector motors have the following disadvantages:

1. The complexity of the repair work, the impossibility of their independent implementation.
2. High noise level.
3. Complex controls.
4. High price.

First you need to make sure that the parameters of the electrical network correspond to the permissible voltage and frequency indicated on the motor housing. The system must be de-energized beforehand.

To connect the collector motor, the stator and the armature must be connected in series. Terminals 2 and 3 must be connected, and 1 and 4 must be closed in a 220 V circuit. Switching on without a differential pressure regulator can generate a starting current of significant power, which will lead to arcing in the manifold.

It is also worth considering the connection diagram of the electric motor through a magnetic starter:

1. Make sure that the starter's contact system will withstand the operating conditions of the electric motor. There are eight load current categories from 6.3 A to 250 A. The value in this case indicates the current strength that the electromagnetic starter is able to pass through the working contacts.
2. The control coil can be rated for 36 V, 220 V, 380 V. The 220 volt option should be selected.
3. After collecting the circuit of the electromagnetic starter, connect the power section. At the output of the power contacts, an electric motor is switched on, a 220-volt input is connected in parallel.
4. Then you should connect the buttons "Stop" and "Start".
5. It is necessary to connect "zero" to the second output of the electromagnetic starter.

Star connection

This method is suitable for the connection diagram of a three-phase 380 V. Phase conductors (A, B, C) are connected to the beginning of the windings (C 1, C 2, C 3) through the switching apparatus. The ends of the windings must be aligned at one point.

Such a circuit of the electric motor will not allow it to develop all its power, because the voltage on each winding will be 220 V. The ability to connect the electric motor in a star circuit is confirmed by the Y symbol on the plate.

This motor connection can be easily distinguished in the terminal box due to the jumper located in the middle of the winding leads.

Delta connection

In order for a three-phase electric machine to be able to develop the maximum provided power, an asynchronous motor connection diagram should be used in the "triangle" method.

The winding leads must be connected in the following order:

• C 2 with C 4;
• C 3 with C 5;
• C 6 s C 1.

The line voltage between the wires in three-phase networks will be 380 V. With this connection option, the wiring may not be able to cope, because it contributes to the occurrence of inrush currents. This connection is possible if there is a Δ symbol on the motor plate.

To fully understand how to connect a 3-wire motor, you should know about the combination connection. In this case, the star connection is applied first., then in the operating mode of the winding switches to "delta".

You should always remember in the process of working with electrical appliances about strict adherence to safety rules. All actions must be performed only in the mode of de-energized equipment.