162. The transformer laminations are insulated from each other by
A. mica strip
B. thin coat of varnish
C. paper
D. any of the above
163. Which type of winding is used in 3-phase shell-type transformer?
A. Circular type
B. Sandwich type
C. Cylindrical type
D. Rectangular type
164. During open circuit test of a transformer
A. primary is supplied rated voltage
B. primary is supplied full-load current primary is supplied current at reduced voltage
C. primary is supplied rated kVA
D.
165. Open circuit test on transformers is conducted to determine
A. hysteresis losses
B. copper losses
C. core losses
D. eddy current losses
166. Short circuit test on transformers is conducted to determine
A. hysteresis losses
B. copper losses
C. core losses
D. eddy current losses
167. For the parallel operation of singlephase transformers it is necessary what they should have
A. same efficiency
B. same polarity
C. same kVA rating
D. same number of turns on the secondary side.
168. The transformer oil should have volatility and viscosity.
A. low-low
B. high-high
C. low-high
D. high-low
Page 24 of 45