Answer Posted / mohd.rizwan qureshi

when the full voltage applied to the stator winding ,the
rotor of 3-phase cage induction motor fails tostart.This
happenes whe the no. of stator and rotor slots are equal
or an integral ratio.so due to strong alingment of forces
are produced between stator and rotor at the instant of
starting. these forces create an alingment torque greater
than the accelarating torque.The phenomenon of magnetic
locking between stator and rotor teeth is called cogging or
teethl ocking.

HOW TO CALLICULATE RESITENCE,REACTANCE AND IMPEDENCE VOLTGE OF TRANSFORMER 13.33 KVA 144/240 VOLTS 93/56 A WITH FORMULA

1523

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control & auxilary circuits used for circuir breakers

1477

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what is allowed value of zero sequence impedancce of 6.6 kv nuetral earthing transformer ?what is the actual value

1655

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How 3 phase invertor works?

1497

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how can service sitting be setted for MCCB?Example for sittings IR (CURRENT RATING),IS(CURRENT STARTING)IO (current operating)?

1971

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redundant connection in contactor?

2056

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standard earthing rating for power line..

1669

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what is meant by 3rd hormonics ?

1398

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Is it possible to measure correct value of earth resistance & cable insulation ristance with out disconncting earth lead & both sides of cable ends? If not, any other method to measure ER & CIR with out disconneting from the system.

1650

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why -48 volts dc used in telecommucation

1980

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What is tranformer differtial?

1465

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Can clean earth cable be considered as low current cable

1548

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What is nichols chart?

770

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What does the term supermesh means?

666

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we have earthmat at 110KV substation.we would like to take earth resistance.b some says that by connecting earth megger terminals (C1,P1) at middile point of earthmat (at riser) will cause voltage gradient at other earthmat nods and dont get exat earth resistance.when connecting at end nods will get exat value . is it correct .please explain

1716

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