Answer / kunal

by varying the voltage
as per V/f ratio

Answer / sss

frequeny of a transmission line is varied by changing the synchronous speed of the generator.....which is affected by the equation syn.speed=(120f)/p...so the frequency of the transmission line is varied by changing the poles of the generator...........
however the frequency cannot be maintained as a constant one throughout....it has a slight variation of +/- ...but if there is huge variation the power station tries to decrease/increase the load there by maintaining the frequency as a constant one

How i can select current transformer and meters for the upgrading the panal..for 200kw to 600kw....i need to select monitoring and protection ct,s and apmpire meter ,kw meter too.

1 Answers  

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what are the usual topology of transformers at different substations in the power system and why that particular topology is choosen. what are the limitaions of that topology?

0 Answers  

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why we use core type and shell type transformers?

2 Answers  

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IF I USED VVVF DRIVE IN FAN APPLICATION MOTOR IN 6.6 KV ( 700 KW) MOTOR & DURING NORMAL RUN OPERATION TIME IF RPM SUDDENLY REDUCE IN MOTOR BY DRIVE(E. MOTOR RPM REDUCE SUDENLY 687 TO 550 RPM) WAHT WILL BE HAPPEND IN DRIVE

1 Answers  

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Explain Even and Odd signals?

0 Answers   UOG,

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state the working of discharge lamp?

0 Answers  

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Which are resistive loads & which one are inductive loads : Refrigerator, Split air conditioner, ceiling fans, well pump, fluoresecent bulbs, T.V, CRT Monitors, Adsl Routers, C.P.U, Printers, Deep Freezers, Speakers, DVD Players, Microwave oven etc. ? Output Power for these Appliances Would be same like this : P = V * A * P.F Or would be changed ? thanks

0 Answers  

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about transformer oil material & Test name for the measurement of its dielectric strength & wht will u do if its dielectric strength goes low ?

2 Answers   NTPC,

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Questions :- HR- Q.1 about yourself & family background ? Q.2 Why u choose Power sector as ur carrier starting not any other sector ?? Q. 3 What think abt NTPC ? Techincal Questions:- Q.1 about Vocational Training……What u did , see the main equipments….etc Q.2 Why a transformer Noise during its running condition ? Q.3 about transformer oil material & Test name for the measurement of its dielectric strength & wht will u do if its dielectric strength goes low ? ……..some discussion type ? Q.4 What is relation between transmission lines & Communication lines ? Q.5 Which Machine u will prefer to use at a place where flammable gases are coming out & why ? Q.6 how fault in an electric system is detected & hw protection of equipments is done ? Q.7 Why we didn’t feel electric shock in an electric train ?? Q.8 Anything u want to ask from us ??

44 Answers   Akona Engineering, Bhel, BSES, Cranex, DRDO, JCB, NTPC,

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i have a motor 55kw how u will calculate cable specification for this motor

1 Answers  

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How to calculate the value of capacitance of a capacitor used in power factor improvement plant if we know KVAR and voltages?

1 Answers  

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In constant power region of 3-phase IM torque-speed characteristics, if frequency increases slip A does not alter B decreases C increases D none of above

0 Answers  

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