The case for elimination of stray currents and magnetism in turbomachinery is being recognized as an issue to be dealt with in industries that design and operate rotating machinery. Of main concern are bearings, seals, gears, couplings, etc. Resulting problems extend from surface damage to unit crashes. It is important to recognize the symptoms, to heed the warnings, and to enact preventive and corrective measures. Recommendations are to eliminate or minimize the source, and to bond the machinery to ground, especially the shaft, with a reliable shaft brush and a qualified current monitor. Information and guidance are provided from MPS job files covering some of the 200 installations visited in the past 15 years.

P. L.
, and
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Shaft Currents in Electric Machines
AIEE Trans.
, Vol.
, pp.
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Nippes, P. I., and Sohre, J. S., et al., 1981, “Panel on Electromagnetic Shaft Current Control,” presented at 10th Turbomachinery Symposium, Texas A&M University, Houston, TX.
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