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What is the main disadvantage of phase advancers?

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It cannot be used for motors below 20 H.P.
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Single phase transformer

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Define Amplitude and Phase of Sinusoidal quantity.

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working principle of single phase motor

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Why is a three phase denoted by R, Y, B ?

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phase 1 ,R =Red colour cable terminal, phase 2 Y=Yellow colour terminal cable,Phase 3 B=Blue colour cable terminal, N =Neutral. For identification.

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Explain the working of a single phase capacitor start induction motor. 

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Single phase capacitor start induction motor https://youtu.be/31lvvzU5Puc

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State any four advantages of three phase induction motor. 

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Advantages of three phase induction motor https://youtu.be/27OIOCKN05U

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