Electrical Machines Hopkinson test is conducted under which of the following condition? half load full load no load any of the above half load full load no load any of the above ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : 1. interpole windings are connected in series with armature windings 2. polarity of interpoles must be the same as that of the main poles in advance 3. distortion of the main field under the pole shoes is not affected by the use of interpoles From above, the correct answer is 1 and 3 2 and 3 1 and 2 1 alone 1 and 3 2 and 3 1 and 2 1 alone ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Short circuit test is performed on a transformer with a certain impressed voltage at rated frequency. If the short circuit test is now performed with the same magnitude of impressed voltage, but at frequency higher than the rated frequency then The magnitude will both increase. The magnetude of current will increase, but power factor will decrease. The magnitude of circuit as well as the power factor will decrease. The magnitude of current will decrease but the power factor will increase. The magnitude will both increase. The magnetude of current will increase, but power factor will decrease. The magnitude of circuit as well as the power factor will decrease. The magnitude of current will decrease but the power factor will increase. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generator, lap winding is used in high voltage and low current applications. high current and low voltage applications. where greater load is connected. where constant speed is required. high voltage and low current applications. high current and low voltage applications. where greater load is connected. where constant speed is required. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by varying the speed. changing the load. changing the field excitation. varying the applied voltage. varying the speed. changing the load. changing the field excitation. varying the applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V, DC shunt motor is operating at a speed of 1440 rpm. The armature resistance is 1.0 Ω and armature current is 10 A. of the excitation of the machine is reduced by 10%, the extra resistance to be put in the armature circuit to maintain the same speed and torque will be 2 .1 Ω 1.8 9 Ω 1.79 Ω 3.1 Ω 2 .1 Ω 1.8 9 Ω 1.79 Ω 3.1 Ω ANSWER DOWNLOAD EXAMIANS APP