(1) When the voltage exceeds 10% of the rated voltage of the motor or less than 5% of the rated voltage of the motor, the motor is prone to heat under the rated load, and the temperature rise is increased. The voltage should be checked and adjusted.
(2) The phase imbalance of the three-phase power supply voltage exceeds 5%, causing the three-phase current to be unbalanced, causing the motor to generate extra heat, and the voltage should be adjusted.
(3) If the one-phase fuse is broken or the power switch is in poor contact, causing the phase loss to run and overheating, the damaged component should be repaired or replaced.
(4) The winding wiring is wrong. If the star is connected to a triangle, or the triangle is connected to a star by mistake, running under the rated load will overheat the motor and should be checked and corrected.
(5) Short-circuit or grounding between the stator windings or between phases, so that the current increases, the loss is increased and the heat is overheated. If the fault is not serious, just re-inser the insulation and replace the winding seriously.
(6) One-phase winding of the stator is broken or one of the parallel windings is broken, causing the three-phase current to be unbalanced and the windings to overheat.
(7) The cage rotor broken strip or the wound rotor coil joint is loose, causing the maintenance network current to be too large and generating heat. The copper strip rotor can be repaired or replaced, and the rotor should be replaced for the cast aluminum rotor.
(8) The bearing is damaged or worn excessively, so that the stator and the rotor are rubbed against each other. The bearing can be checked for looseness and the stator and rotor are not properly assembled.
(9) If the load is too large, the load should be reduced or replaced with a high-powered motor.
(10) If the machine being loaded is faulty and causes an overload, the machine to be taken should be inspected to eliminate the malfunction.
(11) Starting too frequently, the number of starts should be reduced.
(12) If the ambient temperature is too high (more than 40 °C), the motor is too hot and the heat dissipation is difficult. Cooling measures should be taken.
(13) There are too many dust and oil on the inside and outside of the motor, which will affect heat dissipation and should eliminate dust and oil.
(14) The air duct of the motor is blocked, the ventilation is not smooth, and the air intake is reduced. The debris and dirt of the air duct should be eliminated.
(15) The fan inside the motor is damaged, installed or not installed, and should be properly installed. The damaged fan should be repaired or replaced.