Answer / vinod

When three phase voltage is applyed across the stator a
flux with syn speed will be rotated inside the stator, as
the rotar is stationatory max, voltage will be induced and
high startin current is drawn.

Answer / jayaram

iniatially the motor don't have any backemf so motor draw
high current at the starting stage. whenever motor is
started it generates backemf so motor takes normal load
current.

Answer / sanjana singh

in starting motor resistance is negligible.so according to formula-
I=v/Ra ( Ra can be neglected)
then I=V ( Starting current is equal to supply voltage)
so to start motor starter is used. it add resistance in series of motor by this starting current limit to safe value & motor start safely...

What is the meaning of C1, C61, C91 cable

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when i am going to take trail on a 3ph sq.i/m motor 5.5kw, i observed that RPM of the motor is very low as compared to the rated RPM and also it rotates in clockwise in first ON command,and anticlock wise in second ON command. finally i observed that on phase is no available . but iam not clear about, why the motor is rotates in both directions without any phase interchanging.pls answer to my question.

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What is the drawback of static coefficients?

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What happen when increese more than 50HZ fequincy.

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As per BIS, Earth pit resistence value?

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why booster transformer is used in sumpners test conducted on transformer????

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without any excitation we can strt any dc or ac moter?

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Full form of bdv test?

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