The noise produced by a transformer is termed as_______________________?
(A) zoom
(B) hum
(C) ringing
(D) buzz
Which of the following parts of a transformer is visible from outside ?
(A) Bushings
(B) Core
(C) Primary winding
(D) Secondary winding
Which of the following insulating materials can withstand the highest temperature safely ?
(A) Cellulose
(B) Asbestos
(C) Mica
(D) Glass fibre
The efficiency of two identical transformers under load conditions can be determined by_______________?
(A) short-circuit test
(B) back-to-back test
(C) open circuit test
(D) any of the above
Which of the following acts as a protection against high voltage surges due to lightning and switching ?
(A) Horn gaps
(B) Thermal overload relays
(C) Breather
(D) Conservator
A good voltage regulation of a transformer means________________?
(A) output voltage fluctuation from no load to full load is least
(B) output voltage fluctuation with power factor is least
(C) difference between primary and secondary voltage is least
(D) difference between primary and secondary voltage is maximum
Which of the following protection is normally not provided on small distribution transformers ?
(A) Overfluxing protection
(B) Buchholz relay
(C) Overcurrent protection
(D) All of the above
In AC.S.R. conductors, the insulation between aluminium and steel conductors is_________?
(A) insulin
(B) bitumen
(C) varnish
(D) no insulation is required
A conductor, due to sag between two supports, takes the form of____________?
(A) semi-circle
(B) triangle
(C) ellipse
(D) catenary
Transmission voltage of 11 kV is normally used for distances up to_____km?
(A) 20—25 km
(B) 40—50 km
(C) 60—70 km
(D) 80—100 km