Electrical Machines Armature flux is.............with respect to main field flux or main field poles? stationary rotates same direction None of these rotates opposite direction stationary rotates same direction None of these rotates opposite direction ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 6 pole, 50 Hz IM has a rotor speed of 987 rpm find rotor frequency? 0.70 Hz. 60 Hz. 0.65 Hz. 0.75 Hz. 0.70 Hz. 60 Hz. 0.65 Hz. 0.75 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are 2, 3, 4 1, 2, 3, 4 and 5 1, 3, 4, 5 2, 3, 4, 5 2, 3, 4 1, 2, 3, 4 and 5 1, 3, 4, 5 2, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 940 RPM 970 RPM 920 RPM 960 RPM 940 RPM 970 RPM 920 RPM 960 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machine torque depends on which of the following? both A and B flux (φ) speed armature current (I) both A and B flux (φ) speed armature current (I) 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 Remains unchanged. Decreases. Increases. Oscillates around the rated speed. Remains unchanged. Decreases. Increases. Oscillates around the rated speed. ANSWER DOWNLOAD EXAMIANS APP
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