Electrical Machines Hopkinson test is conducted under which of the following condition? full load no load any of the above half load full load no load any of the above half load ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a star - delta starting of an IM applied voltage per stator phase is 57.7 % of a line volt reduced voltage is applied to the stator. resistance is inserted in the rotor. line voltage is 57.7 % of stator voltage. applied voltage per stator phase is 57.7 % of a line volt reduced voltage is applied to the stator. resistance is inserted in the rotor. line voltage is 57.7 % of stator voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What does happen if tripled harmonics given to induction motor? Nothing will happen. Fail to start. Will results in short circuit. Will results in open circuit. Nothing will happen. Fail to start. Will results in short circuit. Will results in open circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the necessity of copper brushes in a dc motors? To convert alternating supply current to direct current. None of these. To increase the flux cutting by the rotor. To absorb the mechanical shocks produced during running condition. To convert alternating supply current to direct current. None of these. To increase the flux cutting by the rotor. To absorb the mechanical shocks produced during running condition. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a step down transformer which one of the following statements is true? Number of secondary turns is less than primary turns. Number of secondary turns is more than that of primary. Secondary power is less than primary power. Secondary current is less than primary current. Number of secondary turns is less than primary turns. Number of secondary turns is more than that of primary. Secondary power is less than primary power. Secondary current is less than primary current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V dc series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 Ω. The value of resistance which must be added to obtain rated torque at 1000 rpm is 2.2 Ω 5.7 Ω 6 Ω 1.9 Ω 2.2 Ω 5.7 Ω 6 Ω 1.9 Ω ANSWER DOWNLOAD EXAMIANS APP