Electric Motors are available in various types of enclosures, each providing different levels of protection and cooling. The enclosure type is selected based on application to protect the motor's bearings, windings, and other parts from dust, moisture, chemicals, mechanical damage, and other contaminants.
Electric motors are everywhere. They are used in various applications, such as cooling fans, machine tools, power tools, pumps, compressors, rolling mills, ships, movers, paper mills, etc. The average lifespan of an electric motor is approximately 40.000 hours. Whether it will hit that mark depends on several factors, which we will discuss in this post, including the level of maintenance. The other important thing is understanding the causes of the failures. Here are the most common ones:
Pollution
Pollution by dirt, dust, and chemicals is considered one of the most critical factors that can damage an electric motor. Those find their way inside the motor and bent dent bearing and balls, which leads to a high vibration level and wears the motor off. The cooling fan blockage factor also leads to the motor overheating and cutting short its lifespan.
To prevent these from happening, make sure you keep the motors and grinding machines as far as possible and, generally, keep the work area as clean as possible. That includes cleaning fixtures, tools, and the work area in general.
Vibration
Vibration can lead to several issues with a motor, including complete failure. As mentioned above, pollution can cause vibration, but there's more to it than that. The main reason for beating is the motor being placed on an uneven surface. Other reasons include misalignment, corrosion, and loose bearings, resulting from an issue with the motor itself.
To prevent or reduce vibration, ensure that the motor is placed on a flat and stable surface. If there's still vibration, check for misalignment, corrosion, and loose bearing.
Over-Heating
Over 50% of insulating failures in motors are the result of overheating. Overheating can be caused by several factors, including low power quality or a high temperature in the work area. Every additional 10OC that the motor temperature gets, the insulation life is reduced by 50%.
To prevent over-heating, keep the motor as cool as possible, ensuring that the work environment is also being kept cool within an acceptable range.
Low Resistance
Overheating (the result of high temperature), corrosion, and physical damage (both effects of pollution). These are the conditions that cause the degradation of the insulation of the windings, which in turn causes low resistance. Low resistance is the most common and complex cause of motor failure to overcome.
To prevent motor failure from low resistance, the insulation should be checked regularly for wear and, if found, replaced it.
Electrical Overload
This is caused by an excessive current flow within the motor windings, exceeding the design current that the motor can carry efficiently and safely. Causes can be low voltage or short-circuited conductors, or an excessive voltage supply.
To prevent electrical overload, install over-current protection to detect overcurrent and interrupt supply.
Comments
Post a Comment