Industry Articles Display
2018-07-31 Plant Engineering
A number of reasons can cause an electric motor to fail. Six reasons are discussed.
By: Avi Patel, EzyTrader
Electric motors are an essential part of an industry and numerous applications and systems depend on them. If they are well-maintained, they will have a long life. However, any failure would lead to a great loss to the organization. Inspect them regularly and ensure that maintenance activities are performed periodically, regardless of whether it is a new or used electric motor. There can be numerous reasons that may cause a motor to fail. Six in particular are:
1. Overheating and high temperatures
If the motors get overheated due to any reason, it may cause a number of performance issues. Overheating may occur when an electric motor is forced to operate in a high-temperature environment as it would cause the rate at which heat can be conducted to reduce at a significant rate. A proper cooling and ventilation system must be in areas where the motors are operated. The ventilation system acts as a backup if the cooling system stops working.
Every electric motor has a design temperature and if it starts off at a bad value, it will start operating in a much warmer condition than the design temperature. The motors should be matched with the ideal current values to prevent overheating. Make sure to check on the heat being dissipated to mitigate the damages caused by overheating.
2. Dirt and contaminants
Dirt is one of the major sources that cause damage to an electric motor. Contaminants can damage the motor by blocking the cooling fan which causes the motor temperature to rise. Dirt can also affect the insulating value of the winding insulation if it settles on the motor windings. The proper steps must be taken to protect the motors from dirt-for example with shielding devices. If the contaminants and pollutants in the air combine with moisture, they can form extremely corrosive substances which will shorten the motor's life.
In certain operating conditions, some electrical devices or used machinery will start to draw more current than their overall capacity. This event usually is quite unpredictable, happens very suddenly, and impacts the motor in a significant way. In order to avoid an overcurrent, install devices that can prevent it. These devices are usually wired in the circuits and automatically shut down the extra amount of current that is flowing in the circuit.
4. Moisture and humidity
Humidity and moisture significantly impact the performance of electric motors. These factors contribute to the corrosion of the motor shafts, rotors and bearings. Moisture may even lead to an insulation failure. Ensure that the motor inventory is kept dry at all times.
If the motors stay inactive for extended periods of time, then they have to be kept warm. Failing to do so will cause the motors to drop near the dew point temperature and they will be at various risks that are caused by the moisture-and-dirt combination. In addition, a relative humidity of under-80% should be maintained even when they are running. This helps reduce the risk of corrosion and damage and extends the lifespan of your motor.
Vibrations can be caused due to a number of reasons, one being the misalignment of the motor. Corrosion of various parts in second-hand equipment can also cause the motor to vibrate. To eliminate this, the alignment of the motor must be checked.
Lubricate the motors properly as over-lubrication or under-lubrication causes equal damage to the motors. It's critical to know exactly how much lubricant and which lubricant to use. Consider the frequency of the lubrication and the possible contaminants that the motors can be subjected to. You can opt for anti-wear and oxidation resistance apart from consistency, viscosity and other factors if different materials are being mixed.
If the motor is properly maintained, many failures can be avoided.
Avi Patel is an engineer by heart and a digital marketer for EzyTrader, a premium marketplace for used equipment.