What is the Necessity of Starter of an Induction Motor?

What is the Necessity of Starter of an Induction Motor?
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1 Answer

Answer :

Induction motors, when direct-switched, take five to seven times their full-load current and develop only 1.5 to 2.5 times their full-load torque. This initial excessive current is objectionable because it will produce large linevoltage drop that, in turn, will affect the operation of other electrical equipment connected to the same lines. Hence, a starter is necessary to overcome this objection.
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The following air gap readings were obtained from a horizontally mounted, bilge pump, induction motor, equipped with sleeve bearings: FWD END-AFT END, Top .045 - .049, Right Side .045 - .047, Left Side .045 - .047, Bottom .045 - .041 Which of the f A. both the aft and foward bearings should be replaced. B. Shims should be removed from the aft bearing. C. The forward bearing should be lowered. D. The aft bearing should be lowered.

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Last Answer : Answer: D

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Last Answer : Answer: C

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Last Answer : Answer: A

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Last Answer : Answer: B

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Last Answer : Answer: D