The short circuited winding so cuts down this voltage of self-induction that the voltage necessary to force the full load current through the secondary when the regulator is in the neutral position is very little more than that necessary to overcome the ohmic resistance of the secondary.
Ques. What effect is noticeable in the operation of a single phase induction regulator?
Ans. It has a tendency to vibrate similar to that of a single phase magnet or transformer.
Fig. 2,420.—Bottom end of stationary element or secondary of Westinghouse polyphase induction regulator.
Ques. Why?
Ans. It is due to the action of the magnetizing field varying in strength from zero to maximum value with each alteration of the exciting current, thus causing a pulsating force to act across the air gap, which tends to cause vibration when the moving part is not in perfect alignment.
Ques. Explain the effect produced by bad alignment?
Ans. If the bearings of the primary be not in perfect alignment with the bore of the secondary, thereby making the air gap on one side smaller than that on the other, the crowding over of the flux to the smaller air gap will cause an intermittent pull in that direction, which will develop vibration unless the primary bearings are tight and the shaft sufficiently stiff to withstand the pull.