Direction of motor rotation
How to determine the direction of rotation of the motor? The question is simple for those who know) Now I will tell you how I determine the direction of rotation. Often the direction of rotation is fundamentally important for the correct operation of any mechanism (drive), so the first thing to check is the direction, or as they say, the phasing of the motor.
It’s clear that a motor can rotate “this way” and “that way.”. Speaking correctly, to the right and to the left. Scientifically speaking, there is right and left rotation. They also say “forward” and “reverse” rotation, or “forward” and “reverse”, or “right-handed” and “left-handed” rotation. The essence is the same.
Since a lot of the literature is in English, I will also say “Forward. Reverse”, or FWD. REV. This is especially common in the manuals for frequency converters, about which I have written extensively on the blog. I will also mention how foreign technical literature defines “clockwise” and “counter-clockwise” rotation. CW and CCW (Clock Wise and Counter Clock Wise). Convenient, I apply.
In this article I will talk only about three-phase asynchronous (induction, according to foreign sources) motor.
By the way, the Royal Academy of Sciences (which can be more authoritative in the scientific world?) in the century before last officially stated that the asynchronous motor is an impractical futile. And now this motor is used in industrial equipment 99% of the time. Where I’m going with this? Do not believe even the most official sources! Check it out for yourself!
What is right hand rotation of a motor
Most electric motors (over 90%) that rotate in machines have “right-hand rotation”.
But the motor (or rather, its rotor) has two ends, which one to look at to determine the direction? The rule of thumb is: Rotation is right-handed when, when viewed “backwards,” the motor’s rotor and shaft will rotate in a clockwise direction.
I learned this rule by heart when Sergey Ivanovich sent me on a business trip to the other end of the country.
How to determine the rotation of electric motors. The first thing to do is to look “in the back” (i.e. on the impeller).
Explanation of the “right” direction of rotation from the Delta frequency converter manual:
If on the shaft side. counterclockwise. This would be Right, or Direct rotation of the motor rotor.
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An example of why it is important to pay attention to the correct direction of rotation of the motor. in the article “How we broke a new German compressor for many thousands of euros”.
Another example is how ridiculously the mechanism for moving the width of the feed on one of the machines was broken. Everything worked as it should. motor turns “right”, reaches the right end, stops. Turns to the left, reaches the left end, stops. But once the engine did not stop, but bent and broke out the metal guides, bringing misery to our mechanics))) Turns out the electrician on the night shift had been instructed to change the input circuit breaker, and he did so without thinking about phasing.
Kolya, hello to you very much, if you read these lines!
20V single-phase motor. problem statement
Let’s assume that the single-phase induction motor which is already connected using the starting capacitance initially rotates clockwise as shown in the picture below (single-phase 220V motor)
Wiring diagram for a single-phase motor
- Point A marks the beginning of the starter winding and point B its end. Brown wire is connected to the start terminal A and green wire to the end terminal.
- Point C marks the beginning of the working winding and point D. its end. The red wire is connected to the start contact and the blue one to the end contact.
- The direction of rotation of the rotor is indicated with arrows.
We set ourselves the task of making a reversal of a single-phase motor without opening its housing so that the rotor begins to rotate in the other direction (in this example against the movement of the hand of the clock). There are three ways to do this. Let’s consider them in detail.
For mechanisms in production or in everyday life, whether it is a wood or metal processing machines, cantilever pump, conveyor belt, crane beam, sharpening machine, electric lawnmower, forage grinder or another device to work without failure, it is necessary, first of all, that the electric motor shaft rotates in the right direction. In order to avoid mistakes and prevent rotation of the machine shaft in the opposite direction according to point 2.5.3 “The rules of technical operation of electric installation of consumers” on the case of the mechanism itself and the drive motor must be marked with arrows of direction of rotation of the electric motor.
Direction of rotation of the motor shaft
Determination of the electric motor rotation direction is performed from the side of the single shaft end. In the case where the motor has two ends of the shaft, the rotation is determined by the side of the shaft that has a larger diameter. According to GOST 26772-85 clockwise motion of the shaft corresponds to the right direction. For the most common three-phase squirrel-cage motors, rotation of the shaft in the right direction will be performed, if the sequence of phases, by which the voltage is supplied to the ends of stator windings, corresponds to the alphabetic sequence of their marking. U1, V1, W1.
For single-phase motors with squirrel-cage rotor, clockwise rotation of the shaft will be possible, provided the phase is at the end of the operating winding.
Change of shaft rotation direction in three-phase electric motors
Operation of some machinery requires left-hand rotation of the shaft. Knowing how to change the direction of rotation of the electric motor, this can be done without any modification or alteration of the drive motor itself. To change the direction of rotation you need:
If the operation of the motor requires constant switching of the motor from right-hand to left-hand rotation, it is connected according to a special circuit,
Reverse a single phase motor
To start the rotation of the single-phase asynchronous electric motor, reconnect the phase to the beginning of the working winding.
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Knowing how to reverse the direction of rotation of an electric motor, you can connect a single-phase electric motor with the ability to switch right-hand rotation to left-hand rotation using a three-pin switch.
Motor Rotation Direction Codes | Spec. Sense
It is important to bear in mind that the washing machine motor does not start via a capacitor, nor is a starter winding necessary for starting.
Before we start connecting, let’s look at what wires are in the transfer case of the washing machine motor:
- the two white ones are from the engine speed sensor (tachogenerator or Hall sensor);
- The brown and red one is for the winding to the stator and the rotor;
- gray and green are from the graphite brushes.
In the photo you can see the wires in the transfer case
The wires that lead to the tachogenerator can be put aside. we don’t need them. In different models of washing machines, the color of wires can be different, and the resistance can be oriented. in those that go to the sensor, it must be 60-70 ohms. After the extra wires are highlighted, the remaining wires need to be “phoned” to find each pair.
220V Washing Machine Universal Motor Direction Change | Forward. Reverse. Clock. Anti Clock
Before starting to work, you should fix the motor firmly to some surface. the shaft will rotate as soon as it is connected to 220 V.
As a rule, motors come with 4 leads (that is, they have 4 wires coming out of the motor). If your motor has 5 pins, 6 pins, or even 7 pins, make sure there are no extra pins among them. we need only the wires from the rotor and stator.
Next, you need to connect the motor according to the diagram shown in the figure below.
The photo shows the connection diagram of a collector motor (pinout)
According to the scheme, you need to connect the stator winding with the rotor brush, so you need to find the appropriate wires and make a jumper between them (it is marked pink in the photo), and then insulate. Connect the remaining two wires. from the rotor winding and the second brush. to the mains.
It remains only to complete the device with on and off buttons. In order to change the direction of rotation of the shaft, it is enough to jumper to other pins.
On old Soviet units may be installed motors with 3 pins. How to connect such a “miracle of technology”?
Motors from old washing machines may have three pins
First of all, you need to measure the resistance: between leads 1 and 2 and 2 and 3 the ohmmeter will show 10 ohms, and between 1 and 3. 20 ohms. Connect the motor as follows: Terminals 1 and 2 to the mains, terminal 3 through a capacitor to terminal 1.
So, to connect the motor from a washing machine is not difficult. Use our recommendations, don’t forget about preventive measures and give a “second life” to your equipment.
In the video, posted below, you can once again get acquainted with the order of connection of the motor from the washing machine.
About the author:
Mom, wife and just a happy woman. Inspired by travel, can’t imagine life without books and good films. Strives to become the perfect hostess, and is always ready to share her experience.
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Astronauts in Earth orbit solve the problem of dirty things in an ingenious way. Clothes are dropped from a spaceship, and they burn up in the upper atmosphere.
Washing machines equipped with “No Ironing” or “Easy Ironing” features can wash laundry with little to no creasing. It achieves this effect due to a special approach to the spin. it is performed at low speed, with long pauses, and a small amount of water is stored in the tank.
To wash small items on the road or in a hotel, it is convenient to use a regular plastic bag. Socks or pantyhose are kneaded inside a knotted bag along with water and a small amount of detergent. This method allows you to pre-soak items and wash them without damaging the fabric or wasting a lot of powder and water.
The first officially patented washing machine was made of wood and consisted of a box with a frame half-full of wooden balls. Laundry was loaded inside, detergent and a lever was used to move the frame, which, in turn, made the balls move and grind the laundry.
Laundry machines have something to do with the origin of the expression “money laundering. In the 1930s, American gangsters used a network of laundromats as a cover for their illegal activities. By passing off the proceeds of criminal activity as proceeds from cleaning clothes, they turned “dirty” money into “clean” money.
There is a washing machine “for bachelors”. Laundry washed in such a machine does not need to be ironed at all! The thing is that the device does not have a drum: some things can be placed inside the container directly on hangers (for example, jackets and shirts), and smaller things (say, underwear and socks). on special shelves.
The expression “soap opera” (“soap”) did not emerge by chance. The very first soap operas and shows with a female audience were broadcast on television while housewives did the cleaning, ironing and laundry. In addition, commercials for detergents (soaps and detergents) were often aired to attract female viewers.
History has it that a kitten got into the drum of a washing machine and, after a full wash cycle on the “Woolen Things” program, got out unharmed. The only trouble for the pet was an allergy to detergent.
There are a variety of balls that are used in the washing machine. Antistatic will not let the fabric stick to the body after washing, balls with special loops will “comb” the lint and prevent the appearance of lint, and silicone with nubbins will not let pile up the down when washing outerwear.
Connection to the washing machine
How to Connect a Motor to a Washing Machine? Features that must be taken into account to connect the electric motor from the washing machine to the 220V network:
- The connection pattern shows that the motor functions without a starting winding;
- There is also no starting capacitor in the wiring diagram. it is not required for starting. But it is necessary to connect the wires to the network strictly according to the diagram.
Each of these motors is designed for 2 mains voltages. There are 2 connection schemes for it.
It is possible to connect the electric motor from a washing machine:
By switching the windings, one achieves a variation of the nominal 1 voltage in 2. With the existing motor jumpers and 6-pole terminal block the jumper position must be changed.
With any connection scheme, the direction of the windings must correspond to the direction of the windings. The star point can be either the base of the winding or its terminus, as opposed to a delta point where they are connected together only in alternating sequence. In other words, the end of the previous winding with the beginning of the next.
Operation of the motor also in single-phase line is allowed, but not with absolute efficiency. Non-polar capacitors are used for this. With the capacitors included in the mains, the maximum power will not exceed 70%.
Connecting the motor 220V from a washing machine
180W GOST 16264.1-85 from the washing machine type Malyutka (Kama-8M) of which there are 4 wires to 2 separate windings, 1
2.4 ohm of active resistance. In the machine was connected without condenser (time relay, thermal relay, button of saving modes./norm.). All the old connections were broken. By connecting directly to 220V I found out that it works (turns, switches the direction of rotation). There are doubts about the long-term performance of such a simple connection scheme.
Resistance values. confused. Not much in ohms. And on the duration. I don’t know, I’ve done a couple of sharpening.
NazAnd wrote: There is a motor AER 16UHL4 220V
180W GOST 16264.1-85 from a washing machine like Malyutka (Kama-8M)
I’m not going to lie, but I similar engines rewound. operating winding seems to be 0,41, and the starting winding, which immediately turns off after start. 0,14mm. This refers to the ZVI with a thermal relay. I don’t think the Malyutka has gone any further.
So it is necessary that the second winding is disconnected after start-up?
avmal wrote: the inrush, which immediately turns off after starting, is 0,14mm
You had in your hands the wire 0.14 mm ?? Its allowable current is 30 milliamps.
NazAnd wrote : The machine was connected without a capacitor. All the old connections were ripped off.
So the capacitor was ripped off the place with connections.
NazAnd wrote : there are 4 wires coming out of it for 2 separate windings, 1
Winding 1. turn directly to 220V winding 2. turn through a paper capacitor 4-6mkF 600V also in 220V.
NazAnd wrote: From a washing machine like Malyutka
usually these machines were in use “till the last breath”, they used to break down because the activator bushing was worn out, backlash appeared, the oil seal was leaking water. it got on the motor and it broke down. As the comrade above said
haramamburu wrote : Resistance values. confused by. not much in ohms.
check the winding to ground and between each other again.Rarely a used washing machine gets a working motor.All with “tarnished reputation” vosnovnom.
4eh wrote : did you hold a 0 wire in your hands.14 mm ??
O-o-o-o-o-o. So you are a Khohol. Then it will be easier to communicate with you. The point is that the winding wire is determined by its diameter.
avmal wrote : So you are a Khohol. Then it will be easier to communicate with you. The thing is, the winding wire is determined by its diameter.
And the katsavs have 0 wire.14mm wire holds more current ??
avmal wrote : The point is that the winding wire is determined by the diameter.
What do you say? ?? You measure current in amps and voltage in volts, don’t you? ??
As a “professional wrapper of all times and peoples” I underlined your wire in red.
4eh wrote: Have the katsapians wire 0.14mm holds more current ??
So. Let’s go to “Chatterbox”. Since you’ll be there to talk to. I have a lot of topics there.
Connecting a 220V motor to a single-phase network in reverse
Reversal of the motor shaft in this case is possible, if there is access to the outputs of its starting and working windings. These motors have 4 leads: two to the start winding connected with a capacitor, two to the operating.
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If there is no information about the purpose of the windings, it can be obtained by means of a wiretap. The resistance of the starter winding will always be greater than that of the working winding due to the smaller cross section of the wire with which it is wound.
In a simplified version of the motor connection diagram, 220 V is fed to the working winding, one end of the starting winding to the phase or zero of the network (makes no difference). The motor starts to rotate in a certain direction. To obtain the reverse circuit, disconnect the end of the starter winding from the contact and connect there the other end of the same winding.
To get a complete working wiring diagram, you need equipment:
The reverse and forward motion circuit in this case is very similar to the connection diagram of the three-phase motor, but it is not the phase but the starting winding is switched in one or the other direction.
How to change the rotation on a single phase motor
Before selecting a wiring diagram for a single-phase induction motor, it is important to determine whether to reverse. If you often need to change the direction of rotation of the rotor for full operation, it is advisable to organize reversing using a pushbutton station. If one-side rotation is enough for you, then the simplest circuit without the possibility of switching is suitable. But what to do if after connecting it you decide that the direction must be reversed after all?
Let’s assume that the single-phase induction motor which is already connected to the starting capacitor initially rotates clockwise as shown in the picture below.
Let’s set a task. to reverse single-phase motor without opening its housing so that the rotor starts to rotate in the other direction (in this example against the movement of the hand of the clock). It can be solved in three ways. Let’s take a closer look at them.
Reconnect the work winding
To change the direction of rotation of the motor, you can only swap the beginning and end of the operating (permanently energized) winding, as shown in the figure. You would think that to do this, you would have to open the case, take out the winding and flip it. You don’t have to do this because it’s enough to work the pins from the outside:
As a result, we get a scheme where points C and D swap places. Now the rotor of the asynchronous motor will rotate in the other direction.
reconnect the starter winding
The second way to organize the reverse of a 220 volt induction motor is to swap the beginning and end of the starter winding. This is done by analogy with the first variant:
After the actions described above we get a diagram as in the figure above: points A and B have swapped places, it means that the rotor began to turn in the opposite direction.
swap the starter winding for the working winding and vice versa
To organize the reversing of single-phase 220 V motor by those methods, which are described above, is possible only under the condition that the leads from both windings with all beginnings and ends are coming out of the case: A, B, C and D. But often there are motors in which the manufacturer has deliberately left outside only 3 contacts. This way he protects the device from different “homemade” devices. But there is still a way out.
The diagram above shows a diagram of such, “problem” motor. Only three wires are coming out of the housing. They are marked with brown, blue and purple. The green and red lines, corresponding to the end B of the start winding and the start C of the work winding, are connected inside. We can not access them without disassembling the motor. Therefore it is not possible to change the rotation of the rotor with one of the first two options.
Take a look at the figure above. Now if you connect a phase to lead D, the rotor rotates in one direction. If we throw the phase wire to the A branch we can change the direction of rotation in the opposite direction. Reverse can be done by manually disconnecting and connecting the leads. The use of a wrench can make operation easier.
Important! The last variant of the reversing connection diagram of the asynchronous single-phase motor is wrong. It can only be used if the conditions are met:
All of these quantities affect the resistance. It must be constant at the windings. If suddenly the length or thickness of the wires is different, then after you organize the reverse, it will be found that the resistance of the working winding is the same as it was before the starting winding and vice versa. This can also be the reason why the motor can’t start.
Warning! Even if the length, thickness and material of the windings are identical, operation with a reversed rotor direction must not be prolonged. This can cause overheating and motor failure. The efficiency in this case also leaves much to be desired.
Tips from the experts
When deciding to connect a motor from an old washing machine to use it for a new purpose, there are two important conditions to be aware of:
In order to be more convenient to deal with the wiring of the transfer box, you need to know its color designations:
Note that in different models of washing machines the color of the wires may vary, but the principle of connection is the same.
Types of motors
The rotation of the shaft of the washing machine is carried out by the motor. It has different design features. The motor can be of the collector, asynchronous or electronic type.
There are several ways to remove the motors from washing machines. First of all, you should disconnect the washing machine from the power supply, sewer and water mains. In this condition, the unit should stay for at least 10 hours. During this time the capacitor will be able to discharge. Only after that you can proceed to the removal of the motor.
Before beginning disassembly
To begin with we need free space. If the machine is in a combined bathroom, the space may be enough, but if the bathroom is only a “meter on a meter”. there will be a lot of inconvenience in the disassembly and repair. The best option. is to move the unit in the garage or outdoors (if you do repairs at the cottage). If there is no such opportunity. move the washing machine to any room where you can find at least 2 square. m of free space. Next it is necessary to perform the following work.
- Cover the working area with an unnecessary cloth or newspapers.
- Move the washing machine to the workplace, having previously disconnected the hoses and wires from it.
- Remove the powder hopper from the machine. it will only get in the way.
- Drain the residual water from the tank by unscrewing the drain filter (underneath).
Also prepare a separate place for small parts and detachable parts. Can immediately put there a receiver for the powder and filter.
Most often, the collector motor in the washing machine stops working, because the brushes are washed. Less often it is due to a defective winding or worn lamellae.
To identify the fault, it is necessary to run the motor. To do this, you must perform a series connection of the stator and rotor windings, and then through the loose connectors to supply alternating current of 220 volts. The motor will start to rotate.
If the washing machine is many years old, the brushes will be almost worn out, and when the motor is running, a strong sparking will be noticeable. Solid brushes are long, have no external defects. Otherwise, it is necessary to remove the brushes from the motor and replace them. New parts should be purchased only original, it will significantly increase the life of the washing machine.
Strong noises, motor heating, incomplete power operation indicates a defective winding. To be sure of this, you need to take a multimeter, select the ohmmeter mode and measure the resistance on the adjacent lamellae. The difference should not be more than 0,5 Ohm. Otherwise, the user will see a short circuit between the coils. Check the stator in the same way. Then you need to diagnose the windings shorted to the stator or rotor case.
If the parts of the motor are serviceable, the resistance values will be very high.
To see if the lamellas are worn, remove the rotor from the motor and inspect the manifold. Flaking of the lamellae, burrs, breakage of the supply contact will inform about the malfunction. This causes the brushes to spark. Usually the lamellas overheat and peel off if the rotor is jammed or there is an inter-turn short circuit.
Another popular machine malfunction is a broken or slipped belt. If the problem occurs frequently, it can indicate a defective pulley. You will need to replace it. It is necessary to disassemble the washing machine, remove the belt, unscrew the fasteners, remove the pulley from the motor and replace it with a new one.
How to turn on a collector-type motor
The appearance of the motors of different models may differ, but the device, the principle of operation is almost identical. The instrument consists of:
- Stator coils (shoes) with two, three leads;
- Two brushes;
- tachoductor (with two, three wires);
- terminal block.
To connect the motor, you need to know the outputs of the armature windings, stator, tacho. The tester will help you not to get confused among the wires.
How to connect an electric motor
Set the tester to the lowest resistance mode, call the tacho, coil, armature windings. Make the connection on the terminals, which are wired to each other to find a pair. If you have a 4 wire design, the red and brown wires are the stator, and the gray and green wires are the rotor. The colors of the wires may vary from one model to the next. Therefore, use a multimeter. You have a meter with 6 wires? The ones on the left regulate the speed of the machine with the tachometer. Their resistance is about 70 ohms. A properly wired unit will pick up speed smoothly, without cracking or sparking. You can check how many revolutions the motor makes with the revolution sensor.
How to start the motor from the washing machine, you can see here:
Adjusting the rotation
There are many ways to control the speed:
- laboratory autotransformer;
- household appliance adjustment board;
- screwdriver buttons, bolt cutters;
- Lighting controllers (switches, toggle switches).
Adjustment scheme is simple, you can make it with your own hands.
This is a satisfactory option for a pump, fan. powerful machines (e.g. machine tools) require a different regulator circuit.
The essence of the matter is to reduce revolutions, preserving operability. The connection is made through a tachogenerator, which transfers the number of turns to the speed regulator chip, which coordinates the cycle with a thyristor.
This board allows you to increase, decrease the speed, but requires constant, intense cooling due to overheating. You can see a detailed video of the speed control, power, connection of the microchip here:
As mentioned above, to change the direction of rotation it is necessary to swap the connection of one of the windings with each other. And the motor starts to rotate in the other direction. Check the correct connection, swap over the leads on the terminal block according to the diagram, switch on the voltage. The direction of rotation of the motor should be reversed. Connect the contact on which phase was connected to the second winding input. Voltage is applied to the vacant terminal, the zero position does not change. You can change the order of connection by flicking the toggle switch.Turn the rocker switch upside down, on the bottom there is a marking of each output and a schematic of their connection in the left and right positions of the switch. To make it easier to understand, draw an elementary connection diagram: two windings and two switch contacts. Connect/disconnect the middle contacts one by one to the two side contacts. The connection is elementary. Connect one coil to the lowermost contact and connect it to the uppermost contact. Connect the second winding to the middle terminal, so that in our example the stator winding is connected. Now connect the rotor. One tumbler contact must be connected to the rotor winding output and the other directly to the neutral supply. If everything is clear, then proceed with the connection. Make diagonal jumpers between the outermost terminals. Connect one middle pin of the tumbler to zero and the other to the second winding.Connect all the leads and check again that the circuit is correct. middle terminal: one is connected to ground and the other to the stator winding. The other end of this winding is connected directly to the supply phase (brown wire). The diagonal tumbler contacts must be jumper-wire connected to the second winding (rotor). Before switching on, be sure to check with a tester for changes of short circuit when the toggle switch is switched.Thoroughly insulate the contacts, check the motor for proper functioning. When switching, the direction of rotation must be reversed. It is strictly forbidden to change the direction of movement until the rotor comes to a complete stop.
The electric motor that turns the drum is the heart of the washing machine. The very first machines were driven by belts which twisted the drum with the laundry. Today, however, the asynchronous machine, which converts electrical energy into mechanical energy, has evolved considerably.
often in the schemes of washing machines there are asynchronous motors, consisting of a stator, which does not move and is intended as both a magnetic core and carrying system, and a moving rotor, which rotates the drum. The asynchronous motor functions due to the interaction of magnetic unstable fields of these structures. Asynchronous motors are divided into two-phase motors, which are less common, and three-phase motors.
The pluses of asynchronous machines include:
- uncomplicated system;
- elementary maintenance involving the replacement of bearings;
- periodic lubrication of the electric motor
- silent operation;
- conditional low cost.
Such motors tend to have a lower cost.
for synchronous speed 3000 r/min. two-phase winding.
for synchronous speed of 500 rpm. symmetrical three-phase winding. Three-phase connection system allows you to change the speed of rotation by switching the winding power.
A motor of the old type usually has 5 wires of black, blue, white, red and green. A series of measurements were made to determine the windings and the resistance between them came out as follows:
Wiring the old motor requires finding the start winding with a multimeter.
- OP. initial winding. It is designed to start the motor only and starts at the beginning until the motor begins to rotate.
- OB. excitation winding. It is the operating winding that runs continuously and turns the motor constantly.
- SB is the button from which the voltage is applied to the starter coil and is switched off when the motor is started.
A little theory on the construction and application of collector motors
Electric motors of this type can be DC or AC, with series, parallel or mixed excitation (for AC only the first two types of excitation are used).
A collector motor consists of a rotor, stator, collector and brushes. Current in the circuit, passing through the rotor and stator windings connected in a certain way, creates a magnetic field that makes the rotor rotate. The voltage is transmitted to the rotor by brushes made of a soft electrically conductive material, most commonly graphite or a copper-graphite mixture. If you change the direction of current in the rotor or stator, the shaft will begin to rotate in the other direction, and this is always done with the leads of the rotor, so that there is no remagnetization of the cores.
If you change the connection of both rotor and stator at the same time there will be no reversal. There are also three-phase collector motors, but that’s another story.
DC motors with parallel excitation
The field winding (stator winding) in a motor with parallel excitation consists of a large number of turns of thin wire and is connected in parallel with the rotor, whose winding resistance is much lower. Therefore, to reduce current during start-up of electric motors with power more than 1 kW include a starting rheostat in the rotor circuit. This connection arrangement controls the speed of the motor by varying the current in the stator circuit only, i.e.к. the way of voltage reduction on the terminals is not very economical and requires a regulator of high power.
If the load is small, then if an accidental break in the stator winding using this arrangement, the speed will exceed the maximum allowable speed and the motor may “run out”
DC motors with series excitation
The field winding of such an electric motor has a small number of loops of thick wire, and when it is connected in series with the armature circuit, the current in the whole circuit will be the same. Electric motors of this type are more robust when overloaded, and therefore most commonly found in domestic appliances.
There are two ways to regulate the speed of a DC motor with a series-connected stator winding:
- By connecting a regulating device that changes the magnetic flux in parallel with the stator. However, this method is rather complicated to implement and is not used in domestic appliances.
- Regulation (reduction) of speed by reducing voltage. This method is used in almost all electrical devices. household appliances, tools, etc.д.
AC collector motors
These single-phase motors have lower efficiency than DC motors, but because of the simplicity of manufacturing and control circuits they are most widely used in household appliances and power tools. They can be called “universal”, i.e.к. they are capable of alternating current and direct current operation. This is due to the fact that when you plug in the AC voltage, the direction of the magnetic field and current will change in the stator and rotor simultaneously, without causing a change in direction of rotation. Reversal of such devices is performed by reversing the rotor ends.
Auxiliary poles and compensation windings are used in AC heavy-duty (industrial) collector motors to improve performance. There are no such devices in the motors of household appliances.
Motor RPM controller from Aliexpress
Inexpensive and effective motor speed regulator is available at a reputable marketplace. When using such a device, there is also no reduction in the power of the motor. The controller is in a hard plastic case, on the front panel of which there is a power button with an indicator and a rheostat switch. The rheostat is connected to the socket with an ordinary plug.
There is a line of wires on the back of the RPM controller, where one pair is “phase” and “zero” and the second pair goes to the electronic engine tachodactor. If only 2 main wires are connected to the washing machine motor through the controller, the motor will run at maximum speed. In order to appear to regulate the speed required necessarily connect the wires coming from the tahodotchik.
Not only motors from washing machines can be connected to such a device, but also motors removed from old drills and other unnecessary power tools. The main thing in preparation for the work correctly perform the installation of the electrical system. Work on connecting the regulator to the motor should be carried out in this sequence:
- Connect the wires going from the controller to the motor. It is important not to mix up the purpose of each conductor.
- Connect the plug to the mains.
- Set the rheostat position to “0”.
- Press the power button.
- Using rheostat select optimal rotor rotation mode.
If the speed controller will be used with only one power consumer, it is enough to turn off the device on the front panel and disconnect it from the mains when the work is over.
Many homemade craftsmen when connecting a controller of this type face one problem. Wires coming from rheostat are made in the connector, which does not fit into the standard socket of most models of washing machines. This problem can be solved by re-soldering a suitable plug strip, which can be purchased in specialized stores or removed from the washer, from which the motor was removed.