Bearing current

Sometimes a coupling insulation as indicated at location 2 in Figure 10.8 may also prevent the eddy currents forming a closed circuit and generate the bearing currents. 

Bearing Currents Caused by Common Mode Voltage. 329... 

Bearing currents due to asymmetry are significant only above a frame size of 400. 

Figure 17.10 Bearing currents caused by common mode voltage...

Figure 17.11 Bearing currents caused by circular flux...

The bearing currents under discussion here do not even arise if the clutch is insulated ... 

Shaft grounding serves to avoid low-frequency bearing currents. It is generally used only on medium-voltage motors. It is expensive and requires frequent maintenance. 

This technology does not avoid bearing currents, but rather provides a low-impedance bypass. Conductive lubricants still lack the quality of traditional lubricants. 

Eane A. C. (1914) Mine water composition, an index to the course of ore-bearing currents. Econ. Geol. 9, 239-263. 

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