Electrical Machines Iron losses in a DC machine are independent of variation in speed. voltage. load. speed and voltage. speed. voltage. load. speed and voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 1, 2 and 3 3 only 1, 2, 3 and 4 1, 3 1, 2 and 3 3 only 1, 2, 3 and 4 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are 4% and 5% from no load to full load. Consider the governors operating at 50Hz on no load. How will the machine share, if the load is 600 MW? generator 2 gets over load 200 MW and 400MW None of these generator 1 gets over load generator 2 gets over load 200 MW and 400MW None of these generator 1 gets over load ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine emf in armature conductors and at the terminals is alternating. current and emf in armature are alternating. current and emf at the terminals are alternating. current and emf in armature are unidirectional emf in armature conductors and at the terminals is alternating. current and emf in armature are alternating. current and emf at the terminals are alternating. current and emf in armature are unidirectional ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous motor the torque is proportional to 1/P² Power P P² 1/P 1/P² Power P P² 1/P ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase star - delta transformer, what is the angle difference between primary and secondary phase voltages? Delta side leads by 30°. Star side lags by -30°. Star side leads by 30°. Delta side lags by -30°. Delta side leads by 30°. Star side lags by -30°. Star side leads by 30°. Delta side lags by -30°. ANSWER DOWNLOAD EXAMIANS APP