What are the main reasons for the heating of the geared motor

Geared motors are widely used in various industrial production lines, conveying machinery, food machinery, medical machinery, printing machinery, textile machinery, office equipment, instrumentation, advertising, amusement facilities and other industries. Sometimes the geared motor is in use. There will be heat generation, so how much do you know why the geared motor heats up?
1. The room temperature is too high
2. Poor heat dissipation
3. Overload
4. Rotor sweep bore
5. Frequent start and stop or frequent forward and reverse rotation
6, the motor is damp
7. The fan is broken or the air inlet and outlet are blocked
8. Bearing lack of oil
9. Overvoltage, undervoltage or unbalanced voltage
10. The load moment of inertia is too large and the starting time is too long
11. Short circuit between turns
12. The internal wiring of the new motor is incorrect
13. The star-delta wiring is wrong
14. Star-delta or self-dual step-down start-up load restart time is long or abnormal conversion due to failure
15. The machine is stuck in a stall
16. Broken bar of squirrel cage asynchronous motor rotor
17. The rotor winding of the wound asynchronous motor is broken or the resistance is unbalanced
18, lack of phase
19.The harmonics of the power supply are too large, such as large rectifier equipment, high-frequency equipment, etc. nearby