Which of the following happens when star-delta starter is used ?

Related Mcqs:

1.  If P is the power of a star connected system then what will be power of an equivalent delta connected system?

   A. P
   B. 3P
   C. P/3
   D. None of the above

   Updated by: muhammad rahim

2. Which of the following happens in Kando system ?

   A. Three phase A.C. is converted into D.C.
   B. Single phase A.C. is converted into D.C.
   C. Single phase supply is converted into three phase system
   D. None of the above

3. If R1 is in series with parallel connected to R2 and R3, what happens to total current if R2 opens?

   A. cannot tell
   B. remains the same
   C. increases
   D. decreases

4. The selection of an electric motor for any application depends on which of the following factors ?

   A. Electrical characteristics
   B. Mechanical characteristics
   C. Size and rating of motors
   D. Cost
   E. All of the above

5. Which of the following motors always starts on load ?

   A. Conveyor motor
   B. Floor mill motor
   C. Fan motor
   D. All of the above

6. For blowers which of the following motor is preferred ?

   A. D.C. series motor
   B. D.C. shunt motor
   C. Squirrel cage induction motor
   D. Wound rotor induction motor

7. By the use of which of the following m D.C. can be obtained from AC. ?

   A. Silicon diodes
   B. Mercury arc rectifier
   C. Motor generator set
   D. Any of the above

8. Which of the following motors is preferred when quick speed reversal is the main consideration ?

   A. Squirrel cage induction motor
   B. Wound rotor induction motor
   E. Synchronous motor
   D. D.C. motor

9. For which of the following applications motor has to start with high acceleration ?

   A. Oil expeller
   B. Floor mill
   C. Lifts and hoists
   D. Centrifugal pump

10. Which of the following alternatives will be cheaper ?

    A. A 100 H.P. AC. three phase motor
    B. Four motors of 25 H.P. each
    C. Five motors of 20 H.P. each
    D. Ten motors of 10 H.P. each