Electrical Machines For small value armature current Ia the torque developed by a DC series motor is proportional to Ia. 1/Ia. √Ia. Ia2. Ia. 1/Ia. √Ia. Ia2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ IM with line frequency f1 and winding factor kw1 and kw2 for stator and rotor respectively the ratio of per phase stator winding emf E1 to per phase rotor winding emf E2 at standstill is given by E1 / E2 = N1 / N2. E1 / E2 = 1. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor when started on no load does not accelerate up to full speed but runs at 1/7th of the rated speed. The motor is said to be plugging. cogging. crawling. locking. plugging. cogging. crawling. locking. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The condition for maximum running torque is 0.5 lagging R = S.X zero 0.707 lagging unity 0.5 lagging R = S.X zero 0.707 lagging unity ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A bipolar dc machine with interpoles has a main-pole flux of ф per pole and an interpole flux of Фᵢ per pole. The yoke of the machine is devide into four quadrants by the main-pole axis and The commutation axis. The flux-distribution in the quadrants will be ½ ( ф + фᵢ ) in all the four quadrants ½ ( ф - фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two diametrically opposite quadrants and ½ ( ф - фᵢ ) in the remaining two Quadrants ½ ( ф + фᵢ ) in two adjacent quadrants and ½ ( ф - фᵢ ) in the remaining two quadrants ½ ( ф + фᵢ ) in all the four quadrants ½ ( ф - фᵢ ) in all the four quadrants ½ ( ф + фᵢ ) in two diametrically opposite quadrants and ½ ( ф - фᵢ ) in the remaining two Quadrants ½ ( ф + фᵢ ) in two adjacent quadrants and ½ ( ф - фᵢ ) in the remaining two quadrants ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Satisfactory commutation of DC machine requires smooth, concentric commutator properly undercut. brushes should smoothly run in the holders. brushes should be of proper grade and size. All of these smooth, concentric commutator properly undercut. brushes should smoothly run in the holders. brushes should be of proper grade and size. All of these ANSWER DOWNLOAD EXAMIANS APP
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