Electrical Machines Maximum allowable moisture content of power transformer insulating oil is generally taken as 20 ppm. 25 ppm. 45 ppm. 35 ppm. 20 ppm. 25 ppm. 45 ppm. 35 ppm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC motors, under trailing pole tips, flux density will_______ ? decrease increase either increase or decrease None of these decrease increase either increase or decrease None of these 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, 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 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Due to magnetic saturation, the flux per pole in a DC machine without brush shift decreases in both generators and the motors with load. increases in generators but decreases in motor with load. increases in both the generators and the motors with load. decreases in generators and increases in motor with load. decreases in both generators and the motors with load. increases in generators but decreases in motor with load. increases in both the generators and the motors with load. decreases in generators and increases in motor with load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc generator operating on load with its brushes on the geometrical neutral axis (GNA), the magnetic neutral axis (MNA) is shifted in the direction of rotation. Now, if the brushes are given a lead of 90° (electrical), then the MNA will coincide with the GNA shift forward by 90° shift forward by less than 90° shift forward by more than 90° coincide with the GNA shift forward by 90° shift forward by less than 90° shift forward by more than 90° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In salient pole synchronous machine, if direct axis reactance and quadrature axis reactance is equal, then power developed due to reluctance is maximum zero any of the above infinite value maximum zero any of the above infinite value ANSWER DOWNLOAD EXAMIANS APP
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