Periodic inspection and maintenance projects during the use of DC motors - Solutions - China Power

Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

Single chip microcomputer STM32L151CCU6

SMD aluminum electrolytic capacitor

Special attention should be paid to the following when the motor is regularly inspected during use:

1. The motor should be kept dry around, and no other objects should be placed inside or outside.

The cleaning of the motor should not be less than once a month. When cleaning, the internal dust should be blown off with compressed air, especially the commutator, coil wire and lead part.

2. Commutator maintenance

(1) The commutator shall be a positively cylindrical surface with no signs of mechanical damage or charring.

(2) After the commutator runs for a long period of time under no load, a brown and shiny hard film is produced on the surface. This is a normal phenomenon. It can protect the commutator from wear. This film must be protected and cannot be used. Abrasive cloth rubbing.

(3) If the surface of the commutator is rough or burnt, it can be finely ground on the surface of the rotating commutator with a sandpaper of “0”. If the surface of the commutator is too rough, uneven or partially concave, the commutator should be turned. The turning speed is not more than 1.5m/s, and the turning depth and the amount of feed per revolution are not more than 0.1mm. The commutator should not move axially during turning.

(4) When the surface of the commutator wears a lot, or after turning, it is found that the mica sheet has a convex appearance. The mica sheet should be milled into a groove of 1~1.5mm with a milling cutter.

(5) When the commutator is turned or the mica is undercut, it is necessary to prevent copper chips and dust from entering the inside of the armature. Because the armature coil end and the tab are covered. After processing, use compressed air for cleaning.

3. Use of brushes

(1) The working surface of the brush and the commutator should have good contact and the brush pressure is normal. The brush should slide freely in the brush holder. When the brush is worn or damaged, replace it with the same size and size as the original brush, and grind it with “0” sand cloth. The cloth is facing the brush, the back is close to the commutator, and the reversing device is used for grinding. Move back and forth.

(2) After brush grinding, use compressed air for cleaning, then make the motor run at no load, then run for 1 hour with light load (1/4~1/3 of rated load), so that the brush is in the commutator A good contact surface is obtained (the contact area of ​​each brush is not less than 57%).

4. Bearing maintenance

(1) When the temperature of the bearing is too high during operation, or when harmful noise is emitted, it may damage or invade foreign objects. The bearing cleaning inspection should be removed. When the steel ball or the slip ring is found to be damaged by cracks or the bearing is cleaned, the use condition is still When not changed, new bearings must be replaced. New grease should be replaced after the bearing has been in operation for 2,000 to 2,500 hours, but not less than once a year.

(2) The bearings must be protected from dust and moisture during operation, and any impact on the inner or outer ring of the bearing is strictly prohibited.

5. Insulation resistance

(1) The insulation resistance of the motor should be checked frequently. If the insulation resistance is less than 1 MΩ, the dirt and dust on the insulation should be carefully removed and cleaned with gasoline, toluene or carbon tetrachloride. After drying, apply the insulating varnish.

(2) If necessary, hot air drying method can be used. The hot air (80 ° C) is sent to the motor for drying with a fan, and the insulation resistance is lowered, then raised, and finally stabilized.

6. ventilation system

The stator temperature rise should be checked frequently to determine if the ventilation system is normal and the air volume is sufficient. If the temperature rise exceeds the allowable value, stop the ventilation system immediately.