Answer Posted / michel j. discouz

Cogging torque take place due to equal no of stator and rotor pole which will cause inter locking between the stator and rotor and cause mechanical locking. To avoid cogging we use different pole of stator and rotor and taking more pole arc of stator so that avoid cogging.

Iin ESP why positive is grounded ? why not negative ?

2553

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what is meant by vector group of a transformer? How can it be derived?

1936

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Explain the role of a car driver as one of a feedback mechanism.

1132

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why high speed tripping relay is used in protection circuit why not normal relay

1372

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What is the difference between isolators and electrical circuit breakers? What is bus-bar?

1102

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What is the difference between circuit breaker and isolator

1176

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Why need 3phase machine double earthing?

1723

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why wire sizes are 3/29 or 7/29 and why not wire sizes are 2/29 or 6/29?

5078

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Why strting torqe high in inducation motor?

2095

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how much cable size required for 70 kilowatt load.

1622

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In Air circuit breaker LSIG protection unit is used. Without fault in cables (2 runs 3Cx150Sq.mm Copper, 1Kv grade, XPLE armored cable IR value is more than 550Mohm @ 500V Megger) and load section Long time Overcurrent protection is triggers and trips the unit. We changed LSIG protection with new factory tested unit. Even then fault is persisting. Please suggest the possible causes

742

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can i use ups power as a raw power for another ups

1917

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Given a collection of points P in the plane, a 1-set is a point in P that can be separated from the rest by a line; i.e. the point lies on one side of the line while the others lie on the other side. The number of 1-sets of P is denoted by n1(P). The maximum value of n1(P) over all configurations P of 19 points in the plane is 18

2107

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How to calculate cable size by using load.?? Any formula...

1313

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What is the loss of transformer of 220kv/11kv, 63/80 MVA and 18.05% impedance

1940

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