DGVCL Exam Paper (11-12-2011) It is difficult interrupt a capacitive current because It has a leading power factor Current magnitude is very small The restriking voltage can be high Stored energy in the capacitor is very high It has a leading power factor Current magnitude is very small The restriking voltage can be high Stored energy in the capacitor is very high ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) An AC series circuit has R = 6 Ω, XL = 20 Ω and Xc = 12 Ω. The ciruit power factor will be 0.6 lagging 0.6 leading 0.8 lagging 0.5 leading 0.6 lagging 0.6 leading 0.8 lagging 0.5 leading ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) A fixed step by step procedure for finding the solution of a problem on computer is called Algorithm Hardware Software Logic Algorithm Hardware Software Logic ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Which motor is used to start heavy loads? Series motor Shunt motor Cumulatively compounded motor Differentially compounded motor Series motor Shunt motor Cumulatively compounded motor Differentially compounded motor ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Torque in d.c motor = k* φ * IaIn series motor φ α IaTα I²starting torque of dc series motor is high
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 6 % 0.4 % 4 % 5 % 6 % 0.4 % 4 % 5 % 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 purpose of interpoles in DC machines is to nullify The demagnetizing effect of armature mmf The cross-magnetizing effect of armature mmf Both the cross-magnetizing mmf and the reactance voltage The reactance voltage The demagnetizing effect of armature mmf The cross-magnetizing effect of armature mmf Both the cross-magnetizing mmf and the reactance voltage The reactance voltage ANSWER EXPLANATION DOWNLOAD EXAMIANS APP interpoles is widely use to improve commutationplace between main poles fitted to yokefunctions:to neutralize armature mmf in commutating zoneto produce some flux in commutating zone