Why Motor OEMs Are Choosing Helwig’s BPK™ Shaft Grounding Solution

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A span of 6 bpk brushes on our silver graphite brushes page, example of shaft grounding solutions from Helwig Carbon, Bearing Protector Comparison: Carbon Fiber Rings vs. BPKs blog post, BPK Spread 3D Renders

With a growing number of shaft grounding brush assemblies on the market today, it can be difficult to determine which solution works best for your particular application. As a supplier to OEM motor manufacturers for over 30 years, Helwig Carbon’s shaft grounding solutions have continually evolved to accommodate a wide range of applications. 
As the use of VFDs to control electric motors grows, so does the demand for our after-market Bearing Protection Kits™ (BPKs). Explore the factors that make Helwig’s BPKs a preferred choice among OEMs.

1. Easy Installation and Cost-Effective

A critical consideration for motor OEMs is the ability to install the solution quickly and efficiently to keep manufacturing costs low. Helwig Carbon’s team of experienced engineers  work with motor OEMs to provide easy-to-install kits. Our BPKs can either be mounted internally within the motor or externally in the motor OEM mod shop with a customized mounting bracket. Some BPKs are so easy to install, it takes less than a minute!

In addition, one Helwig BPK model can be used on a variety of motor frame sizes and shaft sizes. This advantage has helped reduce the inventory and part numbers for the OEM to keep in their system, further reducing costs.

2. Unparalleled Performance

Perhaps the most critical aspect of a shaft grounding solution is its performance to protect the motor bearings from electrical damage. To do this, the kits must provide the least resistance path to ground any harmful induced shaft currents. This is where Helwig’s shaft grounding assemblies excel. Our proprietary silver graphite brush provides an ultra-low resistance path to ground throughout the life of the kit. The positive spring force within the kit always ensures consistent contact between the brush and the motor shaft. The spring force plus the cleaning action of the brush grade will keep the brush track clear from contamination while the motor is running. These two features set the BPK apart from grounding rings and other assemblies. 

Lab and field testing show the superiority in performance of the silver graphite brush and spring solution over the carbon fiber ring.

examples of shaft voltage, demonstrating the need for shaft grounding solutions

A: Unprotected motor           B: Motor with a carbon-fiber ring                 C: Motor with a BPK-4

3. Longevity

Performance is a key consideration when choosing a shaft grounding assembly, however, high performance won’t yield results unless that performance is consistent throughout the life of the motor. The brushes used in Helwig’s BPKs are specifically designed to provide many years of effective shaft grounding performance. The life of a kit will easily surpass the warranty period of the motor. In fact, depending on the model of BPK and the operating conditions of the motor, some kits have a projected life that exceeds 10 years! 

The current that flows through the brush in a shaft grounding application is so low that the electrical wear is almost nonexistent. The only wear is mechanical, from the friction of the brush against the motor shaft. The proprietary silver graphite brush grade has lubricating properties that help to lower the coefficient of friction between the brush and shaft. This allows our BPKs to have an extra-long life.

Get Started With Your Custom Assembly Today

Simply put, there is no other shaft grounding brush on the market that provides the ease-of-installation, the quality of performance, or the longevity of a Helwig Bearing Protection Kit. That’s why more and more OEMs are adopting our solution. 

The following OEMs are currently working with us on offering Helwig BPKs installed in their new motors: ABB/Baldor, Regal Beloit, Nidec, North American Electric, Teco-Westinghouse, WEG, Worldwide Electric, and many more. Next time you need a new motor, contact your preferred motor provider and insist on the Industry’s Best Shaft Grounding Solution.

BPK-IM2 internally mounted in Century Juggernaut motors.


shaft grounding solution: BPK-SB externally mounted with a custom bracket on a WEG motor

BPK-SB externally mounted with a custom bracket on a WEG motor


shaft grounding solution: BPK-4 externally mounted using 3M™ Dual Lock™

BPK-4 externally mounted using 3M™ Dual Lock™

Kevin Koenitzer
Business Development Coordinator

Helwig Carbon Products, Inc. is the premier, family-owned, American manufacturer, of carbon brushes, brush holders, spring assemblies, bearing protection kits, metal graphite brushes, and mechanical carbons. Since 1928, we have forged innovations that have since become industry standards and requirements. We pride ourselves on manufacturing all of our products to the highest standard and performance because we know your application depends on it!


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