Motor overheating issue

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Not necessarily; it depends on the ambient temperature and the quality of the motor.

Factors such as whether the motor’s operating voltage is too low, the size of the load, ambient temperature, and cooling conditions, etc

First, determine whether it is the bearing area or the stator coil area that has a high temperature. Check whether the cooling fan is clogged, whether the motor’s operating current is too high, and whether the vibration at the bearing area is above the acceptable level.

You can use a clamp meter to measure the current to see if it exceeds the rated value; if it doesn’t, there’s no problem. Check as well to see if there are any issues with the cooling fan. 1. Bearing overheating (causes are varied). Additionally, the motor should be lubricated once a year in general, while motors that run continuously should be lubricated every six months. When lubricating, remove the old oil first and fill the bearing housing to about 70% capacity. 2. Electromagnetic issues (it may be a quality problem with the motor itself; domestic small motor manufacturers are prone to such problems)

Overload, superflow, problems with axial flow fans, dirty air ducts, internal short circuits, harmonic overload, bearing issues, and uneven airflow can all cause the motor to overheat. Each specific problem needs to be analyzed individually, and solutions should be sought by considering the actual conditions on site

I. Excessively high motor temperature or smoking: This fault is a sign of overheating in the motor. There are many reasons for this: there are factors external to the motor (such as poor quality of power supply, excessive load, high ambient temperature, and poor ventilation, etc.) ； There are also reasons related to the motor itself. Common causes and solutions for the motor itself: 1. Incorrect winding connection, with star connection mistakenly made into delta or vice versa. 2. Short circuits between turns or between phases in the stator windings, or ground faults, cause an increase in current and thus an increase in copper losses. If the fault is not severe, only repacking the insulation is required; in severe cases, the windings need to be replaced. 3. An open circuit in one phase of the stator windings, or a broken connection in one of the parallel windings, causes an imbalance in the three-phase currents, leading to overheating of the windings. 4. Rotor bar breakage. The copper bar rotor should be welded or replaced, while the cast aluminum rotor must be replaced. 5. Rubbing between the stator and rotor. It is possible to check whether the bearings are loose, and whether there are any issues with the assembly of the stator and rotor. 6. High ambient temperature, excessive dirt on the motor surface, or blocked ventilation channels ； 7. Motor fan failure, poor ventilation ； II. Bearing overheating: Bearing overheating occurs when the temperature of the motor’s rolling bearings exceeds 95°C, and the temperature of its sliding bearings exceeds 80°C. The reasons and countermeasures are as follows: 1. If the bearing is damaged, it should be replaced. 2. The rolling bearing grease is insufficient, excessive, or contains impurities such as iron particles. The amount of grease should not exceed 70% of the volume of the bearing and its cover; it should be replaced if impurities are present. 3. The bearing and end cover are either too tight or too loose in fit. If it is too tight, machine the bearing housing; if it is too loose, insert a steel sleeve inside the end cover. 4. The end covers or bearing covers of the motor are poorly assembled. Level the end cover or bearing cap shoulder and tighten the screws. 5. The drive belt is too tight or the coupling is poorly assembled. Adjust the belt tension and correct the coupling. 6. If there is too little lubricating oil in the sliding bearing, if it contains impurities, or if the oil ring is stuck, oil should be added, the oil replaced, and the oil ring repaired or replaced. 7. Excessively large or small bearing clearance ； 8. The motor shaft is bent.