Answer / rajkumar

for making -more time
for breaking-less time why?

when moving contact starts leave from fixed contact
during breaking at that time arc will develope this arc
follow to the moving contact upto rest position of the
contact but arc quench media didnot allow this process
incase breaking cpacity is more means arc presence in
between contact is long time so it is damage the breaker

during making moving contact touch or very near to the
fixed contact on that short time only arc produce

Answer / sudheer

because of the inductance associated with the circuit, it
takes time to establish magnetic fields around all the
wires and whatnot. This requires extra current at startup.

Answer / kumar

when we make the circuit ON at that time a suddern inrush
current the steep traveling current wave) flow to the
network or to the device due to the presence of circuit
parameters like as inductance, capacitance. that time the
current value is more than the breaking current.Thats why
the making capacity is more than the breaking capacity.

Answer / guest

if any fault is create in systeam at the time breaker must
be open in within seconds ( it is 2 to 3 sec. )otherwise
very denger fault is create and we loss a very costly
equipment.

Based on CPI/CGPA they shortlist the candidates & than directly start Interview so there is no Written Exam or GD Only PI.Interview held @ MNNIT , ALLAHABAD On-Campus on 6th,Aug, 2007 & the Questions asked to me by Interview Board ( 4 People) are from HR/SummerTraining/BTP/Subject-core, POWER SYSTEM & MACHINE. time duration of I/V is about 15-20 Minutes. HR- Q.1 Name,hobbies & About family background ? Q2.What u know abt NTPC ?? Q3.Why u want to choose NTPC as ur Carrier's starting i.e power sector not any other Oragnisation or sector ?? Techincal Questions- Q1.What is the reason for transformer Noise ?? Q2.Which material is used for making Transformer oil & How u measure its dielectric strength & Name the test ? Q.3 Which Machine u will prefer 2 use if flammble gases are coming out at a place & why ?? Q4.What is relation b/w Transmission Lines & Communication Lines ? Q5.What is the maximum capacity Synchronus Machine & total powerGeneration in our country ? Q.6 In india Power generation is at 50Hz while in America its 60 hz ,why so ?? Advantage or disadvantage ?? Q.7 Maximum Generation Voltage in india ? Q8. What is the Voltage regulation & why its required n how much is permissible ? & causes of voltage variation ?? Q.9 Why electric shock is feel ?? n in a Electric Train why we didnt feel that ? Q.10 Have u seen/ experience of any power plant/ industry related to the power sector ? so these are the questions which not too diffcult i think was asked to me.

6 Answers   NTPC,

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what is the diff.between neutral and earth?

4 Answers  

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In a 3 phase induction motor(without connecting supply) if we rotate its rotor by hand and check resistance of stator winding at motor terminal box its resistance varies why ??

3 Answers   Jindal,

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How transformer winding & oil gets heat.

3 Answers  

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what happen if the battery is charged by more than one source ,for ex: connecting data cable to laptop & charger pin to source supply ? 

2 Answers  

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what is meant by motor protection relay & its working principle ?k

1 Answers   Pricol,

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what is Harmonic effect?

2 Answers  

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what will be the difference on output when 3phase I.M. is given a delta or star supply?

3 Answers  

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why we are useing capciter in EB meter?

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Why CT's shall not be kept open?

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4 Answers   DLF,

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4 Answers  

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