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

what is the type of pilot wire in pilot relay?

1 Answers  

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I have been using an 600VA with 0.6 p.f UPS with my desktop which has 450W power supply unit. Can anyone explain how can this happen . Because the output of the UPS is 360W (600*0.6) (<450W)

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how to calculate the cable size

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WHY TRANSFORMERS ARE RATED IN 11KV 22KV 33KV Instead off 10kv 20kv 30kv

5 Answers  

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Why the Potential transformer Primary in connected to Earth?

2 Answers  

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what is the major difference between dc generator and synchronous generator?

4 Answers  

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what is the distance maintained between the power and data cables with respect to the KVA .... plss give me the formula

1 Answers  

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Differnce between negative Pahse SequenceFunction and unbalance Function?

0 Answers   Atsco, LMW Lakshmi Machine Works Limited,

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I find that underground strip-armoiured,4core,LT PVC cables in an earthed power distribution sytem are occasionly found in charred condition-with no trace of it except ash. Is this because of no proper earth connection/continuity (giving rising to high armour resistance)in the joint enroute or because of insufficient capability (again due to high armour resistance)of cable-armour to carry fault current or due to neglected /unprotected overloading of the cable or due to high armour currents caused by power thefts where only phase(s) are unauthorisely tapped & at the point of poer consumption earth terminal is established by burring underground a not so good earthing rod (or using an underground water pipe for the purpose)

1 Answers  

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why 3 phase motors are preferable over single phase motors ?

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If UG power cable both ends are to be earthed or what? If not why?

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A logic circuit that provides a HIGH output if one input or the other input, but not both, is HIGH, is a(n)?

0 Answers   Ittiam Systems,

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