Why is starter necessary for a three-phase induction motor?
Answer Posted / saurabh
at the time of starting slip S= 1, so the rotor resistance
which depends on slip i.e.
R2(1-S)/S will be equzl to "0",
i.e. rotor will act as short circuit.
hence initailly motor will draw heavy amount of current.
So in order to reduce this inrush current(5 to 7 times of
rated current), we apply less input voltage at the time of
starting so that input curent will be low(as in case of
star connection) & after some time or specified time input
will be fed in Delta connection.
if u understand this then ok other wise read more books in
details...
Is This Answer Correct ? | 164 Yes | 24 No |
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