 Common Servo Motor Troubleshooting and Maintenance

Ⅰ. What are the tasks to be done before starting the AC servo motor?

1. Measure the insulation resistance (not less than 0.5m for low-voltage motors).

2. Measure the power supply voltage, check whether the motor wiring is correct, and whether the power supply voltage meets the requirements.

3. Check whether the starting equipment is in good condition.

4. Check whether the fuse is suitable.

5. Check whether the motor grounding and zero connection are in good condition.

6. Check whether the transmission is defective.

7. Check whether the motor environment is suitable, and remove flammables and other sundries.

Ⅱ. What are the reasons for the overheating of AC servo motor bearings?

1. The motor itself:

(1) The inner and outer rings of the bearing are too tight.

(2) There is a problem with the shape and position tolerance of the parts, such as the poor coaxiality of the machine base, end cover, shaft and other parts.

(3) Improper selection of bearings.

(4) The bearing is poorly lubricated or the bearing is not cleaned properly, and there are sundries in the grease.

(5) Shaft current.

2. In terms of use:

(1) Improper installation of the unit, such as the coaxiality of the motor shaft and the shaft of the device being dragged.

(2) The pulley is pulled too tight.

(3) The bearing is not well maintained, the grease is insufficient or exceeds the service life, and it becomes dry and deteriorated.

Ⅲ. What is the cause of the unbalanced three-phase current of the AC servo motor?

1. The three-phase voltage is unbalanced.

2. Poor welding or poor contact of a certain phase branch inside the motor.

3. The motor winding is short-circuited between turns or phase-to-phase to ground.

4. Wiring error.

Ⅳ. How to control the speed of the AC servo motor?

The servo motor is a typical closed-loop feedback system. The reduction gear set is driven by the motor, and its terminal (output end) drives a linear proportional potentiometer for position detection. The control circuit board compares it with the input control pulse signal, generates a correction pulse, and drives the motor to rotate forward or reverse, so that the output position of the gear group is consistent with the expected value, so that the correction pulse tends to be 0, so as to achieve the AC The purpose of precise positioning and constant speed of servo motor.

Ⅴ. Observe whether sparks and the extent of sparks are generated between the carbon brushes and the commutator when the AC servo motor is running and repair it

1. There are only 2 to 4 very small sparks. At this time, if the surface of the commutator is flat, it is not necessary to repair in most cases.

2. There is no spark, no need to repair.

3. If there are more than 4 very small sparks, and there are 1 to 3 large sparks, it is not necessary to disassemble the armature, but only need to use sandpaper to grind the carbon brush commutator.

4. If there are more than 4 large sparks, you need to use sandpaper to grind the commutator, and you must remove the carbon brush and armature, and replace the carbon brush to grind the carbon brush.