How to check the motor armature at home?

The anchor of the electric motor refers to the rotating part, on which dirt collects, a deposit is formed. In case of malfunctions, it is possible to perform diagnostics at home using a visual and a multimeter. On rubbing surfaces there should be no chips, scratches and cracks. If they are found, measures are taken to eliminate them.

Typical malfunctions

The motor armature under normal operating conditions is not subject to wear. Replace only the brushes, measuring the permissible length. But with prolonged loads, the stator windings begin to heat up, which leads to the formation of carbon deposits.

Due to mechanical influences, the motor armature may be skewed if the bearing units are damaged. The engine will work, but the gradual wear of the lamellas or plates will lead to the final failure of it. But to save expensive equipment often it is enough to carry out preventive maintenance and the device can be used for a long time.

To the negative factors that affect the anchor of the electric motor, it is the moisture that penetrates the metal surfaces. Critical is the long-term exposure to moisture and rust. Due to red clusters and dirt, friction increases, this increases the current load. The contact parts are heated, the solder can peel off, creating a periodic spark.

The service center can help, but it will require certain costs. With the breakdown, you can handle it yourself, by reading the question: how to check the motor armature at home. For the diagnosis you need a device that measures resistance and tools.

How is the fault diagnosed?

The check of the motor armature begins with the determination of the fault itself. The complete failure of this node is due to the scattered brushes of the collector, the destruction of the dielectric layer between the plates, and also due to a short circuit in the electrical circuit. In the case of sparking inside the device, it is concluded that the current collectors are worn or damaged.

The sparking of the brushes begins because of the appearance of a gap in the place of contact with the collector. This is preceded by a drop in the device, a high load on the shaft during jamming, as well as a violation of the integrity of the solder on the winding leads.

The fault on the running motor is indicated by typical conditions:

• Spark is the main symptom of a malfunction.
• Humming and friction when the armature rotates.
• Sensible vibration during operation.
• Change the direction of rotation when the anchor trajectory is less than the revolution.
• Appearance of a smell of melting plastic or strong heating of the case.

What should I do if there are any deviations in my work?

The frequency of rotation of the motor armature is kept constant. At idle, a malfunction may not occur. Under load, friction is compensated by an increase in the current flowing through the windings. If deviations in the work of the Bulgarian, drill, starter become noticeable, then the supply of voltage should be removed.

Continued use of the device may result in a fire or electric shock. First, it is recommended to inspect the body of the product, assess the wiring for integrity, the absence of fused parts and damage to insulation. The temperature of all parts of the device is checked by touch. Hand try to rotate the anchor, it must move easily, without jamming. If the mechanical parts are intact and no contaminants are transferred to the disassembly.

Diagnostics of internal parts

The winding of the motor armature should not have carbon deposits, dark spots similar to the effects of overheating. The surface of the contact parts and the gap area should not be chilled. Small particles reduce engine power and increase current. It is not necessary to disassemble the appliances with the plug included in the network for the safety of the work.

It is recommended to shoot the disassembly process in order to avoid difficulties in the reverse process. Or you can write down every step of your actions on a sheet. Some wear of brushes, slats is allowed. But if you find a scratch, you should find out the reason for their origin. Perhaps, this contributed to the crack in the body, which can be seen only when loaded.

Working with an ohmmeter

Sincere could be due to the loss of electrical contact in one of the slats. To measure the resistance, it is recommended to place probes on the side of the current collectors. Rotating the motor shaft, observe the dial readings. The screen should have zero values. If the figures slip even a few ohms, then this speaks of carbon deposits. When infinite values appear, they judge a break in the chain.

Regardless of the results, the resistance between each adjacent lamellae should be checked further. It must be the same for each measurement. With deviations, all connections of the coils and the contact surface of the brushes should be inspected. The brushes themselves should have uniform wear. When chips and cracks, they are subject to replacement.

The coils are connected to the core by a wiring that could peel off. Solder often can not withstand impacts from falls. With a starter, the current through the contacts can reach 50A, which leads to burn-out of poor-quality connections. External inspection determines the location of damage. If no faults are found, the resistance between the lamellae and the coil itself is measured.

If there is no ohmmeter?

In the absence of a multimeter, a 12 volt power supply and a light bulb for the corresponding voltage will be required. Any car enthusiast with such a set will not have problems. Connect the positive and negative terminals to the plug of the appliance. In the gap put an incandescent lamp. The result is observed visually.

The armature shaft is rotated by hand, the lamp burns without jumps of brightness. If damping is observed, a faulty motor is judged. Most likely, an interturn fault occurred. The complete disappearance of the glow indicates a break in the circuit. The reasons may be non-contact brushes, a break in the winding or lack of resistance in one of the slats.

How to "revive" a faulty device?

Repair of the motor armature begins only after full confidence in the malfunction of the unit. Scratches and chips on the lamellae are removed by a circular groove surface. Carbon black and soot can be removed with cleaning agents for contact electrical connections. Broken bearings are re-pressed and replaced with new ones. It is important to observe the balancing of the shaft during assembly.

Rotation should be easy and without noise. Damaged insulation is restored, you can use the usual insulating tape. Connections that cause suspicion, it is better to disintegrate again. In case of problems with the armature coils, it is recommended to resort to rewinding, which can be performed independently.

Coil recovery

Rewind the motor armature can be in the conditions of the garage, only it is required to be careful when applying each turn. Copper wiring is selected similar wound. The cross section can not be changed, this will lead to a violation of the high-speed operation of the engine. Dielectric paper will be required to separate the windings. Coils at the end of pour lacquer.

A soldering iron and the skills of using it will be required. The joints are treated with acid, rosin is used to apply tin-lead solder. When dismantling the old winding, count the number of turns and apply the same amount of new winding.

The case must be cleaned of old varnish and other inclusions. For this, a file, a nest or burner is suitable. For the anchor, sleeves are made, the material is electrical cardboard. The resulting blanks are laid in the grooves. Wrapped coils should be done with the right turns. The conclusions from the collector's side are rewound with a kapron thread.

Each wire is soldered to the corresponding lamellae. The assembly must end with the next measurements of the resistance of the contact connections. If everything is OK and there are no short circuits, you can check the operation of the electric motor under voltage.