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Mechanic Falls, Maine — June 18, 2015 — AEGIS High-Frequency Ground Straps ensure a very low-impedance path to ground for the high-frequency currents generated by VFD-driven motors and systems.
Non-zero impedances within a ground system can give rise to transient voltages and ground system currents that can travel along motor shafts and damage motor bearings.
Generally recognized as the most efficient path to ground for high-frequency currents, high-frequency grounding straps are recommended by major motor and drive manufacturers to bond the frames of motors and other system components to equalize their earth potential and eliminate ground loops.
AEGIS HF Ground Straps are specially engineered for the lowest possible impedance to the high-frequency currents generated by VFDs. These 12-inch-long flat-braided, tinned copper straps are designed with a circular hole on one end for easy installation around the foot mounting screw of NEMA- or IEC-frame motors and a ring terminal on the opposite end. Custom lengths and terminations are available upon request.
Variable frequency drives (also known as VFDs, variable speed drives, or inverters) can save 30 percent or more in energy costs, but they can also damage motors. VFDs induce high-frequency voltages on the shafts of the motors they control — voltages that can discharge through motor bearings, destroying them in as little as three months and damaging coupled equipment. AEGIS Shaft Grounding Rings provide effective long-term protection of bearings against damaging VFD-induced currents. By channeling these currents away from bearings and safely to ground through the motor frame, they mitigate frosting and fluting damage, premature bearing failure, and costly motor system downtime.
Together, AEGIS Shaft Grounding Rings and AEGIS HF Ground Straps provide system-wide protection against damaging high-frequency currents — from motor shaft to earth ground.
For more information, visit www.est-aegis.com.
