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Answer Posted / sandipan gandhi
At the time of starting motor draws very high strating
current due to very small armature resistance & absance of
back EMF.
To restrict high starting current,at starting stator is
connected in star & after 5-15sec(depending upon motor use
purpose)delay is connected in Delta with the help of star-
delta starter.
current in star connection: i=(V/1.732)/Z
current in Delta connection: i=V/Z
After 5-15sec motor pick-up it's rated speed & devolp back
EMF.
| Is This Answer Correct ? | 55 Yes | 2 No |
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