Electrical Machines A 240 V DC series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 ohms. The value of resistance which must be added to obtain rated torque at 1000 rpm is 6 ohms. 5.7 ohms. 1.9 ohms. 2.2 ohms. 6 ohms. 5.7 ohms. 1.9 ohms. 2.2 ohms. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The crawling in the induction motor is caused by low voltage supply improper design of stator laminations high loads harmonics developed in the motor low voltage supply improper design of stator laminations high loads harmonics developed in the motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Semi closed slots or totally closed slots are used in induction motors, essentially to increase pull out torque reduce magnetising current and improve power factor improve starting torque decrease starting torque increase pull out torque reduce magnetising current and improve power factor improve starting torque decrease starting torque ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a DC series motor is Proportional to field current. Proportional to the armature current. Proportional to the square of the armature current. Inversely proportional to the armature current. Proportional to field current. Proportional to the armature current. Proportional to the square of the armature current. Inversely proportional to the armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The slip of an induction motor normally does not depend on synchronous speed. rotor speed. core loss component. shaft torque. synchronous speed. rotor speed. core loss component. shaft torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines On what factors the speed of dc motor depends? Armature current Ia. Field flux. All of these. Applied voltage. Armature current Ia. Field flux. All of these. Applied voltage. ANSWER DOWNLOAD EXAMIANS APP