Learning Centre

A Motor Shaft Grounding Module (or for short, a MSGM) is a device used to divert harmful electrical voltages away from motor bearings, preventing bearing frosting or fluting and extending the lifespan of the motor.

Aaki motor shaft grounding modules provide a low-resistance path for electrical currents to flow to the ground, rather than passing through the motor’s bearings. This is achieved using a highly conductive copper graphite conductive brush that maintain contact with the motor shaft while the motor is running. For a more detailed explanation of the theory behind its operation, head over to our video area here in our learning center.

Yes, by preventing electrical damage to the motor’s bearings, a MSGM can significantly extend the motor’s operational lifespan, especially in environments shaft currents are generated through the use of Variable Frequency Drives

Variable Frequency Drives are the usual culprit, so any motor that is using some form of speed control is a good candidate for MSGMs.

• Wind Turbines: In wind turbines, MSGMs prevent electrical pitting and fluting in bearings, essential for the turbine’s generator longevity.
• HVAC Systems: VFDs have become prevalent in these systems. Aaki MSGMs enhance the reliability and efficiency of HVAC system motors by preventing electrical bearing damage.
• Pumps and Compressors: MSGMs are used in pumps and compressors to prevent electrical erosion of motor bearings, especially when these are controlled by VFDs.
• Electric Vehicles (EVs): In the EV industry, MSGMs protect motor bearings from electrical damage, ensuring motor durability and performance.
• Industrial Automation: These modules play a key role in automated manufacturing and processing plants, reducing maintenance costs and downtime.
• Marine Applications: MSGMs are vital for extending motor life and ensuring reliability in the challenging conditions of marine environments.
• Elevators and Escalators: They are used in elevators and escalators to prevent electrical bearing damage, contributing to the safety and reliability of these systems.

In these varied applications, MSGMs are instrumental in enhancing motor performance and extending their operational life by preventing electrical bearing damage.

We designed the motor shaft grounding modules to be very easy to install. For shops that expect to install more than a few, we have a number of drill templates, spacers and extensions to help the installer deliver a professional looking product in less time and with less effort.

Its a good question and slightly difficult to answer.  The brushes are high quality and made with 70% copper, which typically means they will last a long time:  3 to 10 years is typical and often they will last the life of the motor bearings.  There are a few factors that can decrease the longevity of the MSGM.

• The condition of the shaft also plays a big part of brush life.  Rough shafts will tend to wear the brush down quicker.  However, this kind of wear typically slows down as the copper brush tends to fill the pores of a rough shaft effectively providing a smoother wear surface.
• The environment the motor operates in can significantly reduce brush life. High dust areas or areas with corrosive or abrasive particles in the are can adversely impact brush life.
• High levels of VFD generated eddy currents and shaft voltages can reduce brush life significantly.

We recommend performing an inspection on the modules at least monthly for the first 6 months to determine a wear rate.  Our proprietary Brush Life Window(tm) on our motor shaft grounding modules makes it easy to quickly check remaining brush life.  From there a scheduled inspection and maintenance plan can be developed that will ensure your motor shaft grounding modules perform their function and operate for years.

To maximize the module’s lifespan:

1. Perform monthly inspections during the first six months to establish the wear rate, then adjust the inspection frequency accordingly.
2. Use the Brush Life Window™ for quick and easy monitoring of the brush’s condition.
3. Based on the initial wear observations, create a tailored maintenance plan to extend the module’s life and ensure its effective performance.

Regular maintenance and monitoring are crucial for the durability and functionality of your MSGM.

We recommend on motors over 5 Hp that two units be installed where possible (one at each end of the motor on both shafts).

Unfortunately, there is no easy way to know or even measure if your electric motor system is generating eddy currents that can damage your bearings. It depends upon many factors such as motor condition, motor load, RPM, grounding conditions, etc. Some electric motor systems can operate for years without a problem and then a change is made to how the system operates or how other systems operate in the plant and the bearings begin to be eroded. The Aaki motor shaft grounding module offers one more level of protection against these costly premature motor failures.

When electric motors are being driven by VFD’s there is a likely chance that the bearings will fail without a MSGM installed.

MSGMs are almost always installed when a motor sent in for repair was being driven by a VFD.

However, many of our customers put these on brand new motors prior to commissioning.

The reason is simple:  When a motor fails when on a VFD, its difficult to determine the exact cause.  Bearing failures can be a result of poor shaft alignment, improper greasing, contamination of the bearing, overloading of the shaft, out of tolerance speed or load conditions, and Variable Frequency Drive setup.

Regardless of what the culprit was, the motor repair shop is often left holding the bag in an attempt to help out a good customer.  So the fractional cost of putting a MSGM on as a failure prevention component will save both the repair shop and the end customer time, reputation, and money.

Basically its cheap insurance.

Since Aaki’s MSGM is designed to be durable, rugged, and easy to install, we have seen it applied in a number of applications. If you think of it as a way to allow electricity to move to or from a rotating shaft, then the use cases open up considerably. Here are a few examples:

• Reduction of electrical noise in Electric Vehicle motors. Our MSGMs have been used to reduce high frequency noise in motors to help meet certification criteria
• bearing erosion on salt water pumps. These brushes have been used to reduce cathodic erosion of pump components for salt water firefighting pumps on barges
• Agricultural equipment
• Reducing static charges that build up on rotating equipment to mitigate the potential for dust explosions
• Cathodic protection of boat propellers
• Satellite systems
• Electroplating equipment.

Well, we are Engineers, Machinists, Designers and Manufacturers first and Marketing guys second so we are working on it but we aren’t always that quick in that department. Have a good name? Drop us a line…

We build in a window that allows you to look at the amount of remaining brush life on the module. You don’t have to pull the brushes or remove any components to see the remaining brush life. We did this to ease the inspection process.

Aaki motor shaft grounding modules are designed, assembled and tested in Calgary, Alberta, Canada

When mounted to the outside of a motor, Aaki motor shaft grounding modules are not Explosion proof rated.  However, we have had some customers mount the modules on the inside of the motor and rely on the Ex rating of the motor housing to do the job.

We have never had one return in the 20 years we have been producing these. Depending upon normal wear and tear, we have sent out repair kits for handles, locking pins, cable and clamps, but the main spools body has turned out to be almost indestructible. Having said that, it’s still important to inspect, test and service them regularly as per your companies maintenance and testing program.

No, some spools are mounted in shops, used for aircraft refueling, rail industry, coal hoppers in paint shops, well heads, anywhere they are pumping or moving any type of fluid that is non-conductive and the static generated can create a fire or explosion.

We have found that the majority of our customers prefer the 12 gauge stranded steel cable with yellow jacket. This cable works well with our 6” spool, providing a compact system for most static bonding applications. However some companies prefer to use a heavier gauge cable. For this purpose we also carry a 4 gauge high strand count copper cable with yellow jacket. This fits well on our 8” spool. The type of spool and gauge of cable would be determined by your company requirements. If you require help in choosing the right setup for your needs, drop us an email or give us a call. We would be happy to help.

There is a 4” distance between flanges and the core is a 2” diameter

Aaki bonding spools are built to handle voltages and currents associated with static electricity.  This means that the spool will handle high voltages and very low currents.  Grounding applications typically require the device to handle generator voltages (120V to 600V) and currents that may be present during a fault condition (ranging from milliamps to tens or hundreds of amps).

The system design is often fundamentally different.  For instance the clamp on a bonding spool is designed to pierce insulating material (such as paint or corrosion).  The piercing point has a very small surface area and can’t handle a lot of current.  Conversely, clamps for grounding applications often have a large surface area that contacts the grounding pole.  This allows the clamp to transfer large currents without overheating.

Bonding is the act of electrically connecting two objects together so that the potential difference between them is close to zero volts.

Grounding is the act of electrically connecting an object to the earth, also known as earthing. Grounding also has the implication that significant currents may be involved, whereas bonding applies mainly to the conduction of very small currents.

Depending whether its on the shelves ready to ship or requires some manufacturing, our products can ship in as little as 5 – 7 business days to process order once placed.  From there, standard shipping times apply.

Depending whether its on the shelves ready to ship or requires some manufacturing, our products can ship in as little as 5 – 7 business days to process order once placed.  From there, standard shipping times apply.

All Aaki products are warrantied for one year against defects in materials and workmanship.

A Motor Shaft Grounding Module (or for short, a MSGM) is a device used to divert harmful electrical voltages away from motor bearings, preventing bearing frosting or fluting and extending the lifespan of the motor.

Aaki motor shaft grounding modules provide a low-resistance path for electrical currents to flow to the ground, rather than passing through the motor’s bearings. This is achieved using a highly conductive copper graphite conductive brush that maintain contact with the motor shaft while the motor is running. For a more detailed explanation of the theory behind its operation, head over to our video area here in our learning center.

Yes, by preventing electrical damage to the motor’s bearings, a MSGM can significantly extend the motor’s operational lifespan, especially in environments shaft currents are generated through the use of Variable Frequency Drives

Variable Frequency Drives are the usual culprit, so any motor that is using some form of speed control is a good candidate for MSGMs.

• Wind Turbines: In wind turbines, MSGMs prevent electrical pitting and fluting in bearings, essential for the turbine’s generator longevity.
• HVAC Systems: VFDs have become prevalent in these systems. Aaki MSGMs enhance the reliability and efficiency of HVAC system motors by preventing electrical bearing damage.
• Pumps and Compressors: MSGMs are used in pumps and compressors to prevent electrical erosion of motor bearings, especially when these are controlled by VFDs.
• Electric Vehicles (EVs): In the EV industry, MSGMs protect motor bearings from electrical damage, ensuring motor durability and performance.
• Industrial Automation: These modules play a key role in automated manufacturing and processing plants, reducing maintenance costs and downtime.
• Marine Applications: MSGMs are vital for extending motor life and ensuring reliability in the challenging conditions of marine environments.
• Elevators and Escalators: They are used in elevators and escalators to prevent electrical bearing damage, contributing to the safety and reliability of these systems.

In these varied applications, MSGMs are instrumental in enhancing motor performance and extending their operational life by preventing electrical bearing damage.

We designed the motor shaft grounding modules to be very easy to install. For shops that expect to install more than a few, we have a number of drill templates, spacers and extensions to help the installer deliver a professional looking product in less time and with less effort.

Its a good question and slightly difficult to answer.  The brushes are high quality and made with 70% copper, which typically means they will last a long time:  3 to 10 years is typical and often they will last the life of the motor bearings.  There are a few factors that can decrease the longevity of the MSGM.

• The condition of the shaft also plays a big part of brush life.  Rough shafts will tend to wear the brush down quicker.  However, this kind of wear typically slows down as the copper brush tends to fill the pores of a rough shaft effectively providing a smoother wear surface.
• The environment the motor operates in can significantly reduce brush life. High dust areas or areas with corrosive or abrasive particles in the are can adversely impact brush life.
• High levels of VFD generated eddy currents and shaft voltages can reduce brush life significantly.

We recommend performing an inspection on the modules at least monthly for the first 6 months to determine a wear rate.  Our proprietary Brush Life Window(tm) on our motor shaft grounding modules makes it easy to quickly check remaining brush life.  From there a scheduled inspection and maintenance plan can be developed that will ensure your motor shaft grounding modules perform their function and operate for years.

To maximize the module’s lifespan:

1. Perform monthly inspections during the first six months to establish the wear rate, then adjust the inspection frequency accordingly.
2. Use the Brush Life Window™ for quick and easy monitoring of the brush’s condition.
3. Based on the initial wear observations, create a tailored maintenance plan to extend the module’s life and ensure its effective performance.

Regular maintenance and monitoring are crucial for the durability and functionality of your MSGM.

We recommend on motors over 5 Hp that two units be installed where possible (one at each end of the motor on both shafts).

Unfortunately, there is no easy way to know or even measure if your electric motor system is generating eddy currents that can damage your bearings. It depends upon many factors such as motor condition, motor load, RPM, grounding conditions, etc. Some electric motor systems can operate for years without a problem and then a change is made to how the system operates or how other systems operate in the plant and the bearings begin to be eroded. The Aaki motor shaft grounding module offers one more level of protection against these costly premature motor failures.

When electric motors are being driven by VFD’s there is a likely chance that the bearings will fail without a MSGM installed.

MSGMs are almost always installed when a motor sent in for repair was being driven by a VFD.

However, many of our customers put these on brand new motors prior to commissioning.

The reason is simple:  When a motor fails when on a VFD, its difficult to determine the exact cause.  Bearing failures can be a result of poor shaft alignment, improper greasing, contamination of the bearing, overloading of the shaft, out of tolerance speed or load conditions, and Variable Frequency Drive setup.

Regardless of what the culprit was, the motor repair shop is often left holding the bag in an attempt to help out a good customer.  So the fractional cost of putting a MSGM on as a failure prevention component will save both the repair shop and the end customer time, reputation, and money.

Basically its cheap insurance.

Since Aaki’s MSGM is designed to be durable, rugged, and easy to install, we have seen it applied in a number of applications. If you think of it as a way to allow electricity to move to or from a rotating shaft, then the use cases open up considerably. Here are a few examples:

• Reduction of electrical noise in Electric Vehicle motors. Our MSGMs have been used to reduce high frequency noise in motors to help meet certification criteria
• bearing erosion on salt water pumps. These brushes have been used to reduce cathodic erosion of pump components for salt water firefighting pumps on barges
• Agricultural equipment
• Reducing static charges that build up on rotating equipment to mitigate the potential for dust explosions
• Cathodic protection of boat propellers
• Satellite systems
• Electroplating equipment.

Well, we are Engineers, Machinists, Designers and Manufacturers first and Marketing guys second so we are working on it but we aren’t always that quick in that department. Have a good name? Drop us a line…

We build in a window that allows you to look at the amount of remaining brush life on the module. You don’t have to pull the brushes or remove any components to see the remaining brush life. We did this to ease the inspection process.

Aaki motor shaft grounding modules are designed, assembled and tested in Calgary, Alberta, Canada

When mounted to the outside of a motor, Aaki motor shaft grounding modules are not Explosion proof rated.  However, we have had some customers mount the modules on the inside of the motor and rely on the Ex rating of the motor housing to do the job.

We have never had one return in the 20 years we have been producing these. Depending upon normal wear and tear, we have sent out repair kits for handles, locking pins, cable and clamps, but the main spools body has turned out to be almost indestructible. Having said that, it’s still important to inspect, test and service them regularly as per your companies maintenance and testing program.

No, some spools are mounted in shops, used for aircraft refueling, rail industry, coal hoppers in paint shops, well heads, anywhere they are pumping or moving any type of fluid that is non-conductive and the static generated can create a fire or explosion.

We have found that the majority of our customers prefer the 12 gauge stranded steel cable with yellow jacket. This cable works well with our 6” spool, providing a compact system for most static bonding applications. However some companies prefer to use a heavier gauge cable. For this purpose we also carry a 4 gauge high strand count copper cable with yellow jacket. This fits well on our 8” spool. The type of spool and gauge of cable would be determined by your company requirements. If you require help in choosing the right setup for your needs, drop us an email or give us a call. We would be happy to help.

There is a 4” distance between flanges and the core is a 2” diameter

Aaki bonding spools are built to handle voltages and currents associated with static electricity.  This means that the spool will handle high voltages and very low currents.  Grounding applications typically require the device to handle generator voltages (120V to 600V) and currents that may be present during a fault condition (ranging from milliamps to tens or hundreds of amps).

The system design is often fundamentally different.  For instance the clamp on a bonding spool is designed to pierce insulating material (such as paint or corrosion).  The piercing point has a very small surface area and can’t handle a lot of current.  Conversely, clamps for grounding applications often have a large surface area that contacts the grounding pole.  This allows the clamp to transfer large currents without overheating.

Bonding is the act of electrically connecting two objects together so that the potential difference between them is close to zero volts.

Grounding is the act of electrically connecting an object to the earth, also known as earthing. Grounding also has the implication that significant currents may be involved, whereas bonding applies mainly to the conduction of very small currents.