What are the isolations required for working on IPBD/ Generator?

What are the isolations required for working on IPBD/ Generator?
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1 Answer

Answer :

a. Generator field breaker open and tagged.

b. GT breaker open and earth switch closed. 

c. Barring gear motor stopped and tagged.

d. Generator PT’s isolated and tagged.

e. CB 472 and CB 474 open and PT’s are isolated and tagged.

f. Before doing any work on brush gear 64F1 relay to be taken out. 
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An open occurring within the field rheostat of an AC generator can be detected by short circuiting its terminals and observing a ____________. A. negative deflection of the wattmeter pointer B. positive deflection of the wattmeter pointer C. buildup of alternator voltage D. low, but constant alternator voltage

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Chattering of the collector ring brushes on a generator may be remedied by _____________. A. lubricating brush holders B. reinsulating the brushes C. cleaning the collector rings D. increasing length of pigtail

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If an AC generator experiences voltage failure, the cause may be _____________. A. an open in the field circuit B. the brushes shifting out of the neutral plane C. excessive locked-rotor current D. a rotating slip ring

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Last Answer : Answer: C