Electric motor overload
An electric motor overload is a fault that causes an electric motor to draw more current than it should to perform its normal operations. Overloads occur for various reasons, such as the motor being under-specified for the load, excessive ambient temperature, low voltage or poor connections and additional conditions. Too much current draw can cause the motor to produce excess heat, leading to failure and in extreme cases, an electric shock to personnel.
When a motor becomes overloaded, one of the most common symptoms is a loud humming sound. The humming noise will become louder as the temperature of the magnetic components inside the motor rises. If the problem is not addressed right away, the motor will become hotter, leading to winding failure and possible insulation breakdown. This can cause the poles of the motor to come into contact with each other, leading to severe damage caused by a large explosion of electricity.
In order to protect against motor overloads, the current draw of the motor must be monitored closely. This can be done through the use of overload contactors, fuses, thermal overload relays, temperature sensors, and variable frequency drives. These protective devices are designed to detect an overload condition and then shut off the motor quickly in order to prevent damage.
To prevent motor overloads in the first place, proper motor selection is key. The motor must be chosen for the required load and for the ambient temperature conditions. The motor should also be running at peak efficiency by maintaining good voltage and frequency.
Motor overloads can also be prevented by proper maintenance. All motor connections should be checked for tightness and free of oxidation or corrosion. The motors lubrication should also be maintained at proper levels. Additionally, the motor should be grounded properly and all wiring should be in good condition.
In conclusion, motor overloads can lead to catastrophic failure of the motor, causing severe damage to both the motor and the personnel in the vicinity. In order to prevent this from happening, proper selection, maintenance and monitoring of the motor must be done. With the right protective devices in place, motor overloads can be prevented, ensuring the safety of the personnel and the motor.
