Electrical Machines Which of the following transformer insulating oil generally used in India? Olefin based insulating oil. Paraffin based insulating oil. Naphtha based insulating oil. Aromatics based insulating oil. Olefin based insulating oil. Paraffin based insulating oil. Naphtha based insulating oil. Aromatics based insulating oil. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Use of fractional pitch winding results in reduced leakage reactance. results in reduced axial length of the machine. All of these make it stiffer. results in reduced leakage reactance. results in reduced axial length of the machine. All of these make it stiffer. 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, 5 1, 2, 6 1, 3, 5 1, 4, 6 1, 2, 5 1, 2, 6 1, 3, 5 1, 4, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if the field flux axis is ahead of the armature field axis in the direction of rotation, the machine operating is synchronous generator. synchronous motor. asynchronous generator. asynchronous motor. synchronous generator. synchronous motor. asynchronous generator. asynchronous motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 4 pole, 50 Hz induction motor 4 % slip, calculate frequency of the rotor emf? 2 Hz. 10 Hz. 3 Hz. 50 Hz. 2 Hz. 10 Hz. 3 Hz. 50 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole lap wound dc generator has 4 brushes, if one of the brush is damaged, what will be the change in V, I and P ratings V, I and P V, I/2 and P/2 V/2, I and P/2 V/2, I/2 and P/4 V, I and P V, I/2 and P/2 V/2, I and P/2 V/2, I/2 and P/4 ANSWER DOWNLOAD EXAMIANS APP