Electrical Machines The direction of rotation of a DC compound motor can be reversed by interchanging series field connections. shunt field connections. armature or field connections. armature connections. series field connections. shunt field connections. armature or field connections. armature connections. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machine armature windings are placed on rotor because of the necessity for electromechanical energy conversion. generation of voltage. development of torque. commutation. electromechanical energy conversion. generation of voltage. development of torque. commutation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2 A armature current at no-load, when the armature current is changed to 20 A at loaded condition the speed is 1000 r.p.m. What is the speed at no-load? none of above. 1130 r.p.m. 4575.4 r.p.m. 1037.5 r.p.m. none of above. 1130 r.p.m. 4575.4 r.p.m. 1037.5 r.p.m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is running at rated speed without any additional resistance in series. If an additional resistance is placedin series, the speed of motor Decreases. Increases. Remains unchanged. Oscillates around the rated speed. Decreases. Increases. Remains unchanged. Oscillates around the rated speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which motors are preferred for refrigeration and air conditioning in smaller units? Universal motors. Induction motors. Reluctance motors. Stepper motors. Universal motors. Induction motors. Reluctance motors. Stepper motors. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 1, 4 1, 3, 5 2, 4 ,5 2, 3 , 5 1, 4 1, 3, 5 2, 4 ,5 2, 3 , 5 ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS