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9 out of 10 motors on drives have high shaft voltages that reduce electric motor life.
3 out of 10 motors are failing directly due to these shaft voltages in S.A .

Yes, a 5 year research project shows this startling result, and is therefore no surprise why most overseas companies and motor manufacturers are installing earth rings as Standard on their electric motors.  Increase Motor Life and a 33% reduction in breakdowns is a large saving in any budget.

No insulated bearings required for low voltage motors thereby also saving servicing costs, as well as no waiting for availability of insulated bearings or housings, and above all use it for the “LIFETIME of the motor”


  • Reduce breakdowns by 33%
  • Increase Life of all electric motors on variable speed drives
  • Reduces servicing costs – No insulated bearings or housing required
  • Readily available – No long waiting periods, thereby reducing downtimes
  • Lasts for the “Lifetime of the Electric Motor”.


fig 4

A 150 HP Motor was tested on a VSD Drive, shaft currents were 27.2v Pk-Pk


fig 5

A 150 HP Motor with a shaft brush & no insulated bearing fitted, has reduced shaft currents to only 1.2v Pk-Pk

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