Related Questions

Sparking is discouraged in a DC motor.
In the following question, sentences of a paragraph have been jumbled and labelled as A, B, C and D. You are required to rearrange the jumbled sentences of the paragraph and mark your response accordingly by selecting the correct option. A: An induction motor can, therefore, be made without electrical connections to the rotor. B: Three-phase squirrel-cage induction motors are widely used as industrial drives because they are self-starting, reliable and economical. C: An induction motor's rotor can be either wound type or squirrel-cage type. D: An induction motor or asynchronous motor is an AC electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding.
Below stated are some of the statements about the squirrel cage induction motor. You need to identify which of the following is incorrect. 1. Very poor speed control 2. Although they are energy-efficient white at full load, they need a lot of energy while being started. 3. They are susceptible to voltage variations. 4. The induction motor consumes more current when supply voltage is reduced. 5. They are explosion-proof as there are no brushes which eliminate the risks of sparking.
Consider the following statements: In the above figure, the curves pertain to the DC motor A. Speed vs Armature current characteristic of a DC shunt motor B. Torque vs Armature current characteristic of a DC shunt motor C. Speed vs Armature current characteristic of a DC series motor D. Torque vs Armature current characteristic of a DC series motor
In case of synchronous motor, which of the following are true? a. Synchronous motor is not self-starting b. If the rotor poles are excited by field current and the stator terminals are connected to AC supply, motor vibrates. c. Variable frequency supply is used to start synchronous motor. d. By using frequency converter, a synchronous motor can be brought from standstill to its desired speed.
Sparking at the commutator of a D.C. motor may result in
In a universal motor, the most common cause of brush sparking is
Which of the following is common cause of brush sparking in a universal motor?
Consider the following statements regarding a stepper motor: 1. The rotation angle of the motor is proportional to the input pulse. 2. The motor has full torque at standstill. 3. Speed and electric control signal of the motor vary mutually linearly. Which of the above statements are correct?
Which of the following statements are correct for dc shunt motor? 1. Speed of a shunt motor is sufficiently constant 2. For the same current input, its starting torque is not high as that of series motor 3. The motor can be directly coupled to a load such as fan whose torque increases with speed Select the correct answer using the code given below.