How to judge the quality of DC motor?

To judge the quality of the micro-topography DC motor, first check whether there is a disconnection, and then measure whether the resistance is normal. If it is a brushless DC motor, lead out three phases, turn the rotor, and use a multimeter to measure whether the output AC voltage is normal, and whether the output voltage is proportional to the speed. If it is a brushed DC motor, turn the rotor and use a multimeter to measure whether the output DC is normal. The following will teach you the simple method of judging whether the micro DC motor is good or bad.

1. Observe the reverse spark when the power is turned on. It is good to have no sparks or few sparks, but it is not good that the sparks are connected in a line. If there is a ring fire phenomenon, it cannot be used;

2. When the temperature rises steadily, stop the machine and measure the winding resistance with a multimeter. Generally, the resistance value is a few tenths to several ohms, which is normal;

3. Under rated voltage, the error between the measured speed and the nominal speed should not exceed 10%;

4. Rotate the DC motor by hand. If there is an obvious resistance, it means that there is a short circuit point inside the motor, and smooth rotation is normal;

5. Add 1.2 times the rated voltage, run for 2 minutes, and observe whether there is any abnormality.

6. When connecting the positive and negative poles, there will be a lot of resistance by hand twisting, indicating that the line is normal. On the contrary, that is, there is a breakpoint in it;

7. After the DC motor runs to a stable temperature, the surface temperature of the motor should not exceed 80 degrees Celsius. If it exceeds this value, it means that the temperature rise of the motor cannot pass.

After the above inspection, the DC motor is fine. Auxiliary: Use a multimeter to measure the voltage between the commutator segments. If there is the same regular voltage between the two segments, the winding is normal.