Answer Posted / ashwani malhotra

The main function of magnetic contactor is to prevent
accidently operation after the power failure & again
recovery. Because as soon as power fail the holding coil
release the contacts and it will not operate untill someone
complete the hold circuit again .

A 50Hz,4-pole,3-phase,star-connected synchronous motor has a synchronous reactance of 12ohmsper phase and negligible armature resistances.the excitation is such as to give an open-circuit voltage of 13.2kilovolt.the motor is connected to 115kilovolt, 50hertz supplying. what maximum load can be the motor torque,line current and power factor?

2520

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why ct's&pt'S out put called as burden,why compelsary short ckt the secondary of ct's while removing the burden?

2369

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The transmission does not have options: a)Partition noise b) Flicker noise c) resistance d) Short noise and reason

2497

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what is calculation mathod/formaulla for deciding Size of busbar (Copper/ aluminum)for L.T. panel on Various Fault level like 50kA,25kA,10kA

2848

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What’s electric traction?

1198

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Is better to supply the voltage for static exciter from the auxiliary power source or from the SG terminals? And why?

2001

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i want to learn control schedule for 11kv panel? can any one send the detailed control schedule?

2476

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What is voltage divider rule?

1239

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at what rate the micro controller increment its timer....is it 1micro seconds or 1/(12*10^6) seconds

1841

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how can calculate 1kva generator running time in 1 liter keroscene

2661

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How should i design a 1ph & 3 ph transformer. Kindly let meknow all steps and formulaes related to design from scratch.

2088

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How to calculate energy stored in an inductance?

1186

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Why line VTG = √3 phase VTG in star? How?

1675

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difference between the applicability of nortons and thevenin theorem

2135

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What is the implications when 600 hp motor is started when the unit is running with Transformer of capacity 1500 KVA and DG set of 1000kva

2272

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