Answer / shibuss

In AC generators two types of excitation systems are used
1. Static excitation system &
2. Brush less excitation system
In static excitation system generated AC is stepped down and
converted to DC using rectifier bridges and fed to the field
(Rotor) through slip ring and carbon brush.
In Brush less excitation system the rectifier bridges are
mounted on the shaft of the generator itself. The power for
this rectifier unit is obtained from a permanent magnet
generator mounted on the shaft. The advantage of this system
is that DC power can be directly fed to the field

Answer / guest

it is very simple,do you know then find.

I want to wire sizing calculator which website is available it

1 Answers  

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i am an maintenance engineer. one distribution board have 5 feeder. recently its ELR trips frequently, but it take some times after trip( 10min,20min..)but 3 feeder no load. two feeder only loaded. i checked one feeder IR value all values are above 50Mohm.but B phase to Earth is only 9Mohm.any problem about low value

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Is there such a frequency as 440v 50Hz?

1 Answers  

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if we convert watt into kva,which one formula use by us,pls tell me?

16 Answers   ABB,

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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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As Electricity Generates in MW I w'd like to know What are the factors we have to consider regarding the transmission of electricity from generation station to Public uses(230 V)

1 Answers  

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How can calculate the rating of a servo stabilizer for given a specific load

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What are motor generator sets and explain the different ways the motor generator set can be used ?

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Which system is best for industries 3ph 3w or 3ph 4w?

3 Answers  

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what is the formula of starting current of 3phase and 1 phase motor???

0 Answers   L&T, WFP,

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what is the working of vfd drives.

2 Answers  

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What is the size of cable to be used for a Space Heater in UPS 160KVA of carrying 10 Amps current with 240 V ,1 Phase?

3 Answers  

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