Electrical Machines A 3 - Φ, 400 / 200 V, Y - Y connected wound rotor induction motor has 0.06 Ω rotor resistance and 0.3 Ω standstill reactance per phase. To make the starting torque equal to maximum torque of the motor the additional resistance required 0.78 Ω. 0.66 Ω. 0.24 Ω. 0.45 Ω. 0.78 Ω. 0.66 Ω. 0.24 Ω. 0.45 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines How can the synchronous speed of a 3 - Φ IM be varied? By varying supply voltage. Both (A) and (B). By varying the supply frequency. By varying number of poles. By varying supply voltage. Both (A) and (B). By varying the supply frequency. By varying number of poles. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increases in field excitation of a DC generator, its generated emf increases upto a limit and then remains almost constant. remains constant. increases. decreases. increases upto a limit and then remains almost constant. remains constant. increases. decreases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starter is not used with large DC motor for starting, it will provide execessive voltage drop in line. draw a starting current many times its rated full load current. damage the armature and commutator. all of above. provide execessive voltage drop in line. draw a starting current many times its rated full load current. damage the armature and commutator. all of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which type of motors are preferred in lifts? None of these DC series motors. DC shunt motors. DC compound motors. None of these DC series motors. DC shunt motors. DC compound motors. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of a DC compound motor can be reversed by interchanging series field connections. armature connections. armature or field connections. shunt field connections. series field connections. armature connections. armature or field connections. shunt field connections. ANSWER DOWNLOAD EXAMIANS APP
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