Electric motor systems are the backbone of countless industries, from manufacturing to utilities. Ensuring the motors run efficiently and reliably minimizes electricity use and unplanned downtime and increases productivity. However, all motors have some risk of premature failure, such as electrical bearing damage caused by variable frequency drives (VFDs). This is where AEGIS®️ Shaft Grounding Rings come into play. These innovative rings effectively protect at-risk motor bearings, decreasing the total risk of premature motor system failure.
Understanding the Role of AEGIS Shaft Grounding Rings
Electric motors are vital to practically all industries. AC induction motors are robust machines, but details of their installation create various problems that can impact their performance and longevity.
The Challenge: Electrical Damage in Motor Bearings
Electric motors powered by VFDs often suffer from electrical bearing damage due to shaft voltage. This voltage can discharge through bearings, causing damage that often leads to premature failure, significant downtime costs, and repair/replacement costs. The root cause is that VFDs output imbalanced voltage; the only way to prevent this is with very expensive all-pole sine filters. There are more cost-effective solutions.
The Solution: Effective Shaft Grounding
AEGIS Shaft Grounding Rings avoid voltage discharge through the bearings by providing a direct path for current to flow safely between the motor shaft and frame without passing through the bearings.
Key Features of AEGIS Shaft Grounding Rings
AEGIS Shaft Grounding Rings are packed with innovative features to protect motor bearings. Here are some of the characteristics that set them apart:
- Patented Conductive Microfibers: These rings use unique conductive microfibers that encircle the motor shaft, ensuring millions of discrete points for electrical discharge away from sensitive bearings.
- Environmentally Robust: Other shaft grounding methods are sensitive to humidity and fouling from debris on the shaft. AEGIS rings are insensitive to humidity, and the fibers can maintain electrical contact in the presence of small amounts of dust and debris, by sweeping the debris aside.
- FiberLock™ Channel: This design securely holds the microfibers in place, providing durability and consistent performance under varying operational conditions.
These features collectively ensure that AEGIS Shaft Grounding Rings protect motor bearings with minimal wear and virtually no maintenance required over their lifespan.
Impact on Operational Efficiency
By preventing bearing damage in VFD-powered motor systems, these grounding rings allow the energy savings and other advantages offered by drive control, without the downside of increased risk of motor bearing failure. With that risk mitigated, facilities using drives for motor control can expect lower motor failure rates, and so lower risk of extremely expensive unplanned downtime.
Case Study: “I’d rather install an AEGIS ring and be done with it”
A prime example of these benefits in action occurred at a Midwest paper mill. A 1,000 HP motor was suffering recurring bearing failure due to VFD-induced electrical bearing damage. After the mill installed an AEGIS PRO ring, the failures ceased. A plant reliability engineer summarized, “We want reliability and uptime. It’s case by case when bearings fail. You have to look at the whole motor system. But if I think that in a particular application I might have an issue, I’d rather install an AEGIS ring on the motor and be done with it.”
AEGIS: A Smart Investment for Electric Motor Systems
AEGIS Shaft Grounding Rings are a game-changer for industries that rely on VFD-controlled electric motor systems. By providing a reliable path for harmful stray current, they protect motor bearings and reduce the risk of unplanned downtime. For businesses seeking to optimize their operations, AEGIS Shaft Grounding Rings are a small investment that offer large dividends in reliability.
AEGIS rings also come with a 2-year extended warranty against bearing fluting damage. No other form of shaft grounding comes with a warranty like this.
To learn more about AEGIS shaft grounding and best practices for electrical bearing protection, sign up for a training. We offer monthly live training webinars, and we can also visit your facility to review your exact application.
