Switchgear protections

31. The fuse blows off by

burning
arcing
melting
none of the above

Detailed SolutionThe fuse blows off by

32. H.R.C. fuses provide best protection against

overload
reverse current
fuses provide best protection against A. overload B. reverse current C. open-circuits
short-circuits

Detailed SolutionH.R.C. fuses provide best protection against

33. Overfluxing protection is recommended for

distribution transformer
generator transformer of the power plant
auto-transformer of the power plant
station transformer of the power plant

Detailed SolutionOverfluxing protection is recommended for

34. The main function of a fuse is to

protect the line
open the circuit
protect the appliance
prevent excessive currents E. none of the above

Detailed SolutionThe main function of a fuse is to

35. A short-circuit is identified by

no current flow
heavy current flow
voltage drop
voltage rise

Detailed SolutionA short-circuit is identified by

36. What will be the reflection co-efficient of the wave of load connected to transmission line if surge impedance of the line is equal to load ?

Zero
Unity
Infinity
None of the above

Detailed SolutionWhat will be the reflection co-efficient of the wave of load connected to transmission line if surge impedance of the line is equal to load ?

37. Ionization in circuit breaker is facilitated by

high temperature
increase of mean free path
increasing field strength
all of the above

Detailed SolutionIonization in circuit breaker is facilitated by

38. The fuse rating is expressed in terms of

current
voltage
VAR
kVA

Detailed SolutionThe fuse rating is expressed in terms of

39. When a transmission line is energized, the wave that propagates on it is

current wave only
voltage wave only
both (A) and (B)
power factor wave only

Detailed SolutionWhen a transmission line is energized, the wave that propagates on it is

40. By which of the following methods major portion of the heat generated in a H.R.C. fuse is dissipated ?

Radiation
Convection
fuse is dissipated ? A. Radiation B. Convection C. Conduction
All of the above

Detailed SolutionBy which of the following methods major portion of the heat generated in a H.R.C. fuse is dissipated ?

Page 1Page 2Page 3Page 4Page 5
Test 1Test 2