Motor Failure Statistics You Need To Know
AC motors are the heart of many critical pieces of production equipment. Factories rely on these motors to keep power flowing through their machines reliably, but it’s easy to forget they’re complex components in and of themselves. Without diligent service and maintenance, AC motors can fall victim to their own detractors, which can cause essential equipment to grind to a halt.
It’s important to understand why AC motors fail. Awareness of common failures gives manufacturers the insight necessary to develop better maintenance strategies. Here’s a look at four key takeaways about AC motor failure, courtesy of an Efficient Plant article on motor failure analysis using data from ABB.
51% of motor failures are due to bearing issues.
The fact that more than half of all AC motor failures stem from bearing failure shouldn’t come as a surprise to manufacturing maintenance techs. But rather than take this as confirmation of what they already know, it’s important to look at the key drivers of bearing failure, including lubrication issues, vibration, heat, and misalignment. This data tells us most motor failures are preventable with a quality approach to maintenance.
Manufacturers can save themselves tremendous difficulty and cost, and avoid fault, by investing in the equipment and processes to measure detractors and monitor motor function. Vibration analysis, thermography, and laser alignment all contribute to the detection of preventable issues that, when resolved, help manufacturers avoid failures.
16% of motor failures stem from external factors.
The factory environment is rife with detractors and conditions that contribute to motor failure. With roughly a sixth of all failures stemming from external variables, it’s important for maintenance teams to pay as much attention to the surroundings of a motor as they do to the motor itself.
Ambient heat and moisture, mechanical interrupters, and contamination are all semi controllable variables. Protecting motors with proper housings or taking steps to mitigate the prevalence of external detractors are essential to preserving motor function. Remember, a chief part of maintenance is understanding and addressing the root cause of a failure.
15% of motor failures involve stator windings.
Windings are perhaps the most integral component of AC motors, and they account for roughly 15% of all failures. The most common issues are overheating and overloading. Excessive starting is the most easily recognized cause of overloading, and overheating may be the product of everything from poor venting and cooling to contamination.
Maintenance techs must prioritize overall motor maintenance to safeguard stator windings. Watch for transient voltages, voltage imbalance, harmonic distortion, and other issues that signal damage to windings.
7% of failures involve rotor bars or shaft couplings.
While fewer than one in 10 AC motor failures are attributed to rotor bars or shaft couplings, problems are common enough to warrant attention. Problems with these components are often linked to winding and/or misalignment, which causes excess heat and stress. Be mindful of electromechanical stressors involving these components, and service or replace components before they fail.
Mind your motors
Motors are the lifeblood of critical manufacturing machines. To ensure your motors receive appropriate attention and preventive maintenance, start with a thorough understanding of the most common causes for motor failure.