Electrical Machines Number of slip rings in 3-phase synchronous motor will be 2 1 3 or 4 0 2 1 3 or 4 0 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt motor has external resistance Ra and Rf in the armature and field circuits respectively. Armature current at starting can be reduced by keeping Rf maximum and Ra minimum Ra minimum and Rf minimum Ra maximum and Rf minimum Ra maximum and Rf maximum Rf maximum and Ra minimum Ra minimum and Rf minimum Ra maximum and Rf minimum Ra maximum and Rf maximum ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What does the use the of height flux density value in transformer design lead to? Reduced iron loss. Increase in weight/KVA. Reduced copper loss. Decrease in weight/KVA. Reduced iron loss. Increase in weight/KVA. Reduced copper loss. Decrease in weight/KVA. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 1 at 90°C. 2 at 90°C. 3 at 90°C. 0.5 at 90°C. 1 at 90°C. 2 at 90°C. 3 at 90°C. 0.5 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A series generator is connected in series to a feeder having 0.5Ω resistance to boost the voltage. The induced voltage is given by Eg = 0.6Ia, Ra = 0.2Ω and Rs = 0.3Ω. Find the voltage boosted by the generator, when delivering 400 Amp? 30 V. 60 V. 90 V. 40 V. 30 V. 60 V. 90 V. 40 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 2, 6 1, 2, 5 1, 4, 6 1, 3, 5 1, 2, 6 1, 2, 5 1, 4, 6 1, 3, 5 ANSWER DOWNLOAD EXAMIANS APP
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