Three Phase Distribution Transformer FAQ 4

31. Under what circumstances will the transformer generate an inrush current_____ (A)

A. Switch on B. Switch on C. Switch on and switch on D. Misoperation

32. The dielectric loss of the transformer refers to the _____ (C) of the transformer

A. Copper loss B. Iron loss C. Copper loss and iron loss D. Loss of insulating material

33. Under the condition of 20 ℃, the qualified value of transformer insulation resistance is _____ (C)

A.100MΩ B.200MΩ C.300MΩ D.400MΩ

34. For transformers above 100kVA, when using fuse protection, the rated current of the primary fuse is _____ (C) of the primary rated current of the transformer

A.2-3 times B.1.5-2.5 times C.1.5-2 times D.2.5-3.5 times

35. The external characteristics of the transformer refer to _____ (A)

A. The relationship between the primary and secondary voltages

B. The relationship between the primary and secondary currents

C. The relationship between primary voltage and secondary current

D. The relationship between secondary voltage and secondary current

36. The electrical distance between the 10kV arrester protecting the transformer and the transformer should not be greater than _____ (C)

A.5m B.10m C.15m D.20m

37. The maximum allowable normal overload value of the oil-immersed power transformer installed indoors is the rated capacity of _____ (C)

A.110% B.115% C.120% D.130%

38. In accident overload operation, when the overload multiple is 1.3 times, the allowable overload time is _____ (A)

A.120min B.150min C.180min D.300min

39. The box-type substation consists of (A).

A. High voltage room, transformer room, low voltage room

B. High pressure room, operating room, low pressure room

C. High pressure room, instrument room, low pressure room

D. High voltage room, transformer room, duty room

40. The relationship between the primary and secondary voltage and current of the step-down transformer is (C).

A． High primary voltage and high current B. Low primary voltage and low current

C． High primary voltage and low current D. Low primary voltage and high current