How to prevent the motor from burning out during operation

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There are mainly the following 6 points:

1. Always keep the motor clean. When the motor is running, dust, water stains and other debris are not allowed within at least 3 meters around the air inlet to prevent people from being sucked into the motor. Internally, a short-circuit medium is formed, or the insulation layer of the wire is damaged, causing a short circuit between boxes, an increase in current, an increase in temperature, and burning of the motor. Therefore, it is necessary to ensure that the motor has sufficient insulation resistance and a good ventilation and cooling environment so that the motor can maintain a safe and stable working condition during long-term operation.

2. Keep the motor working at rated current. The motor is overloaded.. The main reason is that the load being driven is too large, the voltage is too low, or the driven machinery is stuck. etc. caused. If the overload time is too long, the motor will absorb a large amount of active power from the power grid, the current will increase sharply, and the temperature will also rise. At high temperatures, the insulation of the motor will age and fail and burn out.

Therefore, when the stepper motor is running, attention should be paid to frequently checking whether the transmission device is running smoothly, whether the concentricity of the reliable coupling is standard, the flexibility of the gear transmission, etc. If any stuck phenomenon is found, the machine should be stopped immediately to find out the cause and eliminate the fault. and then run again.

3. Frequently check whether the three-phase current of the motor is balanced. Three-phase asynchronous motor. The difference between any one of its three-phase current and the average value of the other two-phase currents is not allowed to exceed 10 %, so as to ensure the safe operation of the motor. If it exceeds, it indicates that the motor is faulty and the cause must be found out and eliminated in time.

4. Check the temperature of the motor. Always check the temperature of the bearings, stator, shell and other parts of the motor for abnormal changes., especially if there is no voltage, current and frequency monitoring and no For motors with overload protection, monitoring of temperature rise is more important. Check whether the motor bearings are overheated and lack oil. If the temperature rise near the bearings is found to be too high, stop the motor immediately for inspection. Check whether there are cracks, scratches or defects on the surface of the rolling elements and raceways of the bearing, whether the bearing clearance is too large and shaking, whether the inner ring rotates on the shaft, etc. If any of the above phenomena occur, the bearings must be replaced before further operation.

5. Observe whether the motor has vibration, noise and abnormal smell. If the motor vibrates, it will cause the non-concentricity of the load part connected to it to increase, causing the motor load to increase. , if overload operation occurs, the motor will be burned. Therefore, when the motor is running, especially high-power motors, it is necessary to frequently check whether the anchor bolts, motor end covers, bearing glands, etc. are loose, whether the grounding device is reliable, and solve problems in a timely manner. Noise and odor are precursors of abnormal motor operation and subsequent serious failure. The cause must be discovered and eliminated at any time.

6. Ensure the normal operation of the starting equipment. The technical status of the motor starting equipment plays a decisive role in the normal starting of the motor. Practice has proved that most of the reasons for burned motors are caused by the abnormal working of the starting equipment. For example, if the starting equipment starts due to phase loss, the contactor contacts will arc or spark, etc. The maintenance of starting equipment mainly involves cleaning and tightening. If the contacts of the contactor are not clean, the contact resistance will increase, causing heat to burn the contacts, causing phase loss and burning the motor contactor. The iron core of the contactor's pickup coil will be corroded and dust accumulated, which will cause the coil to not pull tightly, and a strong force will occur. Noise will increase the coil current, burn the coil and cause failure.

Therefore, the electrical control cabinet should be located in a dry, ventilated and easy-to-operate location, and dust should be removed regularly. Frequently check whether the contactor contacts, coil core, and wiring screws are reliable, and whether the mechanical parts are flexible to maintain good technical condition, thereby ensuring smooth start-up without burning the motor.​