DGVCL Exam Paper (11-12-2011) In a power plant, a reserve generating capacity which is not in service but is in operation is known as Firm power Hot reserve Cold reserve Spinning reserve Firm power Hot reserve Cold reserve Spinning reserve ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) If the excitation of a synchronous generator fails, it acts as a Synchronous motor Synchronous generator Induction motor Induction generator Synchronous motor Synchronous generator Induction motor Induction generator ANSWER EXPLANATION DOWNLOAD EXAMIANS APP if excitation of synchronous generator fails, operate as induction motor
DGVCL Exam Paper (11-12-2011) Ybus used in power flow studies and Zbus used in short circuit studies Are inverse of each other Are transpose of each other Have no inter relation Are the same Are inverse of each other Are transpose of each other Have no inter relation Are the same ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) A 3 phase, 6 pole induction motor operates on 440 V, 50 Hz, supply. If the actual speed of the motor is 960 rpm the slip will be 0.4 % 5 % 6 % 4 % 0.4 % 5 % 6 % 4 % ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Ns = 120f/PSlip=(Ns-Nr)/NsNs = 1000 and Nr = 960 from equation of slip, S = (1000-960)/1000S = 0.04 or 4%
DGVCL Exam Paper (11-12-2011) The main advantage of using fractional pitch winding is to refuce Amount of copper in the winding Harmonics in the generated emf Cost of the machine Size of the machine Amount of copper in the winding Harmonics in the generated emf Cost of the machine Size of the machine ANSWER EXPLANATION DOWNLOAD EXAMIANS APP due to fractional pitch EMF can be approximately made into sine wavelosses due to harmonics reducedsaving in conductor materialmechanical strength of coil is increased.
DGVCL Exam Paper (11-12-2011) A fuse is inserted in Phase wire Neutral wire Both phased and neutral wire Earth continuity conductor Phase wire Neutral wire Both phased and neutral wire Earth continuity conductor ANSWER DOWNLOAD EXAMIANS APP
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