Seal grounds motor shaft
Motor Grounding Seal (MGS) uses carbon filament brushes within the seal to redirect shaft current past the bearing and through the end bell to ground. When VFDs are used with ac motors, voltage builds up on the shaft, forcing current to ground through the bearings, causing bearing degradation. The seal not only prevents shaft-current degradation, it also prevents contamination from moisture, dust or dirt.
Inpro/Seal Co. : www.inpro-seal.com