Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A series motor is efficiently suitable for constant speed operation. low starting torque operation. high starting torque operation. none of these. constant speed operation. low starting torque operation. high starting torque operation. none of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the synchronous reactance of alternators in which a given field current of 200 A on short circuit and a generated emf of 50 V on open circuit. Armature resistance is 0.1 ohm 1Ω. 0.23Ω. 0.25Ω. 0.5Ω. 1Ω. 0.23Ω. 0.25Ω. 0.5Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous motor, the damper winding is generally used to reduce noise level only. prevent hunting and provide the starting torque. reduce the eddy currents. provide starting torque only. reduce noise level only. prevent hunting and provide the starting torque. reduce the eddy currents. provide starting torque only. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a synchronous motor is running at synchronous speed, the damper winding produces no torque. both 1 and 2. damping torqe. eddy current torque. no torque. both 1 and 2. damping torqe. eddy current torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation is critical, the power factor of the alternator is lagging power factor. leading power factor. None of these unity power factor. lagging power factor. leading power factor. None of these unity power factor. ANSWER DOWNLOAD EXAMIANS APP