Maintenance is one of the key activities required to keep electric motors operating at high performance levels. Proper maintenance is essential to ensure reliability and long service life. In this article we examine some of the factors that can lead to an increase in motor operating temperature and, consequently, to a reduction in reliability.
In this discussion we have intentionally focused only on aspects related to the accumulation of dirt on the external surfaces of the motor, excluding other factors such as overload, voltage variations, and similar issues.
We therefore describe the external parts most prone to dirt accumulation and explain how to perform effective maintenance in order to maintain maximum motor efficiency.
With regard to MGM motors, it should be noted that brake motors of the BA series are practically unaffected by this issue. The recommendations provided here therefore mainly apply to the BM and SM series.
Why Cleaning Electric Motors Is Important
After several years of continuous operation, the air intake grille located on the upper part of the fan cover of an electric motor tends to become partially obstructed due to the accumulation of dust and debris. This process can be accelerated by the slight oiliness present in the air of many industrial environments.
The reduction in cooling airflow can also be caused by dirt accumulating on the surface of the cooling fan blades, reducing their efficiency.
The increase in motor temperature during operation is not only related to the reduced airflow but also to the accumulation of dirt on the ribbed surface of the motor housing.
Based on our experience, depending on the age and operating conditions of the motor, airflow may be reduced by approximately 10% to 30%, while the external temperature measured on the motor housing may increase by more than 10 °C.
An increase in operating temperature has a negative impact on both the service life and the efficiency of electric motors.
In the following section we outline five key steps for effective motor maintenance that help maintain maximum efficiency.
How to Clean an Electric Motor
The materials required are a soft brush, a cloth and a vacuum cleaner.
It is important to wear appropriate personal protective equipment (PPE). As a general indication (not exhaustive), this may include gloves, safety glasses, a dust mask, work clothing and safety shoes.
The motor must not be powered and precautions must be taken to prevent accidental energization. The motor must also not be hot. The operation must be carried out by trained personnel capable of assessing potential risks.
Key Steps
- Remove the fan cover by unscrewing the fixing screws (usually 3 or 4 screws)
- Use the brush to remove dirt from the grille, both from the inside and the outside
- Finish cleaning the grille with the cloth
- Carefully remove dirt from the fan, taking care not to damage the blades.
- Remove dirt accumulated on the rear shield
- Brush away dirt from the cooling fins, taking care not to damage the motor connection cables
- Vacuum the removed dust
- Reinstall the fan cover by following the reverse order of removal
Cleaning with water or detergents should generally be avoided, as it may cause damage due to oxidation and rust.
Testing the Motor Before Restarting
Before powering the motor again, it is essential to verify that it operates correctly.
To do this, manually check that the shaft rotates freely and that there are no obstructions or slowdowns caused by accumulated debris.
