Electrical Machines A 3 - Φ, 12 pole, 600 V, 50 Hz star connected IM has rotor resistance and stand still resistance of 0.03 Ω and 0.5 Ω respectively. The speed of maximum torque will be 240 rpm. 540 rpm. 450 rpm. 470 rpm. 240 rpm. 540 rpm. 450 rpm. 470 rpm. 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 1, 3, 4, 5 1, 2, 3, 4 and 5 2, 3, 4, 5 2, 3, 4 1, 3, 4, 5 1, 2, 3, 4 and 5 2, 3, 4, 5 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature of DC machine is made of non-ferrous material. silicon steel. insulating material. conducting material. non-ferrous material. silicon steel. insulating material. conducting material. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 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 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The main purpose of providing tertiary winding in a three phase transformer is to suppress harmonic and unbalance in voltage. None of these to interconnect three voltage systems. to carry extra load. to suppress harmonic and unbalance in voltage. None of these to interconnect three voltage systems. to carry extra load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor the 7th harmonic torque may make the motor rotate at (1 / 7)th synchronous speed. This is called crawling. harmonics. cogging. resonance. crawling. harmonics. cogging. resonance. ANSWER DOWNLOAD EXAMIANS APP
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