Electrical Machines Maximum allowable moisture content of power transformer insulating oil is generally taken as 45 ppm. 35 ppm. 20 ppm. 25 ppm. 45 ppm. 35 ppm. 20 ppm. 25 ppm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Series generators are used in which of the following applications? Used as boosters in dc distribution or transmission. All of these Arc welding. Air crafts. Used as boosters in dc distribution or transmission. All of these Arc welding. Air crafts. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The reduced air gap results in an increase power factor. cost of operation. breaking torque. starting torque. power factor. cost of operation. breaking torque. starting torque. 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, 4, 6 1, 3, 5 1, 2, 6 1, 2, 5 1, 4, 6 1, 3, 5 1, 2, 6 1, 2, 5 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? 90 V. 30 V. 60 V. 40 V. 90 V. 30 V. 60 V. 40 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The synchronous speed of an induction motor will be increased by increasing number of poles. speed can not be increased. increasing of frequency. decreasing of frequency. increasing number of poles. speed can not be increased. increasing of frequency. decreasing of frequency. ANSWER DOWNLOAD EXAMIANS APP