On some electrical generating equipment one outboard bearing pedestal is insulated from the bedplate. This should be checked with a millivolt meter and a jumper. With the millivolt meter connectd between the shaft and the bedplate how should the jumper b A. It should be placed from one end of the shaft to the other to eliminate shaft currents. B. It is used to short the + and - in a D.C. generator or Phase A and Phase C in an alternator to eleminate the effects of CEMF. C. It should be placed across the insulating block to increase the shaft current to a point where it can be measured with the millivolt meter. D. It should be placed from the shaft to the pedestal while one reading is taken, then removed to take a second reading. This eliminates the insulating effect of the bearing.

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Answer :

Answer: D

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