SGR
BEARING PROTECTION RING
Application Notes for
Motors up to 100 HP (75 kW)
Improve System Reliability and Production with Zero Maintenance
and Lifetime Bearing Protection
Any motor controlled by a variable frequency drive (VFD) requires bearing
protection. Motors of 100 hp down to fractional hp motors will experience
bearing failures when operated on a PWM drive. AEGIS SGRTM Bearing
Protection RingTM guarantees that bearings will not fail in these motors from
fluting damage for the service life of the motor.
Ground
Install one AEGIS SGR™ Bearing Protection Ring™ on either
the drive end or the non-drive end of the motor. The simplest
installation is to slide the AEGIS SGR™ over the drive end
and fasten it to the motor end bell with the easy to install
mounting hardware included with each AEGIS SGR™
Purpose of Application Notes: Application notes are intended as general guidance to assist with proper application of AEGIS SGRTM Bearing
Protection RingTM to protect motor bearings. All statements and technical information contained in the application notes are rendered in good faith.
User must assume responsibility to determine suitability of the product for its intended use.
www.est-aegis.com
Patented Technology
SGR
BEARING PROTECTION RING
Application Notes for
Motors 100 HP to 1000 HP (75 kW to 750 kW)
Large motors above 100 hp will have VFD induced EDM currents as well as high frequency
circulating currents when they are controlled by VFDs. To protect the bearings, insulate the
bearing on one end and install an AEGIS SGRTM on the other end. If insulating one bearing is not
possible, install an AEGIS SGRTM Bearing Protection RingTM on each end of the motor.
•Motor frame must be well grounded
• AEGIS SGR™ protects motor bearings and attached equipment (gear box,
pillow block, encoder etc)
•Currents are diverted away from the bearings through the AEGIS SGR™
If insulation is not possible, use AEGIS SGR™ on both ends
to mitigate bearing currents
Insulation on one end (usually NDE) and AEGIS SGR™
on opposite end
•Non-Drive End: Bearing
journal should be insulated
or Insulated/Ceramic
Bearing installed to disrupt
circulating currents
AEGIS
SGRTM
on DE
Recommended
insulating Sleeve
NDE
•Install AEGIS SGR™ Bearing
Protection Ring™ on
opposite end of insulation
and Insulated/Ceramic Bearing (usually DE)
Ground
Critical Applications: Insulate both ends and add AEGIS SGR™
Bearing Protection Ring™ on both ends
•Drive and Non-Drive end:
Bearing journals should be
insulated or Insulated/Ceramic
Bearing installed to disrupt
circulating currents.
Insulated Sleeves or Ceramic
Bearings on DE and NDE
•Install AEGIS SGR™ Bearing
Protection Ring™ on drive and
non-drive end to provide path of least resistance for
shaft voltages and to channel VFD induced currents
to ground.
Ground
•AEGIS SGRTM required to protect bearings in attached
equipment (gear box, pillow block, encoder, etc.)
•Install AEGIS SGR™ Bearing
Protection Ring™ on drive
and non-drive end to provide
path of least resistance for
circulating currents and to
channel VFD currents to
ground.
Ground
Large Motors and Generators over 1000 HP (750 kW)
AEGIS iPROTM Bearing Protection RingTM
Rated for 120 amps/3000 Volts peak
Large motors and generators often have
much higher induced shaft voltages
and bearing currents which require a
high current capable Bearing Protection
Ring™.
High frequency circulating
currents induced by variable frequency
drives (VFD) will cause bearing fluting
and catastrophic failure in these motors.
Generators experience current surges
which can cause electrical arcing in
bearings and equipment.
AEGIS iPROTM
• Install AEGIS iPRO™ on both ends of motor or generator if
there is no insulation.
• If one end is insulated install AEGIS iPRO™ on opposite end
of insulation to protect the non-insulated bearing.
Purpose of Application Notes: Application notes are intended as general guidance to assist with proper application of AEGIS SGRTM Bearing
Protection RingTM to protect motor bearings. All statements and technical information contained in the application notes are rendered in good faith.
User must assume responsibility to determine suitability of the product for its intended use.
www.est-aegis.com
Patented Technology