Answer / bala

A.C current having a sinusoidal wave form...D.C current having a straight live wave form.....in A.C power having a power factor....in D.C circuit not having a power factor...

Answer / amit kumar singh

The major differences in AC and DC are as follows:
1)The magnitude of DC does not change as long as load and
source voltage remain same and its mgnitude depends only on
resistance of load. But, in AC it varies as a function of
cosine and its magnitude depends on Impedence (R+jX) of the
load.
2)DC flows in only one direction in a circuit, but AC
changes its direction every half cycle.
3)Due to variable magnitde and direction of AC (oscillating
nature), it has a frequency of oscillation. But, DC has no
frequency (i.e. f=0).
4)AC has Skin Effect (i.e., it flows more at the surface of
conductor and lesser inside the conductor which is the
effect due to its frequency). But, as DC has zero
frequency, it flows throughout the volume of the conductor.

What are various modes for Mechanical interlocking of breakers (for both MCCBs & ACBs)

1 Answers  

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I am designing new project sub station with 220 kV / 11 kV, 40 MVA capacity. This project have many recifier sets, which can generate 3rd harmonics. Now I have to select vector group of This transformer. To minimise 3rd harmonics, what care should I take in selection of Transformer Vecrtor group? If it is Y-Y with open Delta tertiary then what should be the rating & voltage of Tertiary Winding?

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r we are using in gas turbine mark (5) frame (6) (made in india Bhel 1997) Ā

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I Just want do EHS Certified Certification Distance Course From Govt approved,so can any body provide me details.

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AVR is used for the Voltage regulation of the Generator using the feedback signal by exciting the field winding of the generator.But how the field winding will be excited & using what?

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We have a couple of oil tanks at our plant. One of them does not have a lightning arrester installed. My question is it necessary to install an arrestor on every tank or will this particular one be covered by the arrestor installed on the ajdacent tank, Since all the tanks are close to each other. Basically, I want to know that if these arrestors or protection works in a parituclar area of effect or influence. Thanks

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What is the rating of your capacitor bank at your company.

36 Answers   Ajnara Group, Amara Raja, Amol Electricals, Apollo, ATC, Bhagiradha Chemicals & Industries, Bharat, CBRE, Cisco, Government, JLL, MEIL, Reliance, Sterling, TNEB Tamil Nadu Electricity Board, Torrent Pharma, Victory,

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WE HAVE THE DC RECTIFIER 1500A, INPUT VOLTAGE IS 3 PHASE. HOW TO CALICULATE THE LOAD? 3 PHASE SIDE EITHER dC SIDE. PLEASE SUGGEST ME

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What is an automatic controller?

0 Answers  

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An electric bulb giving light but at the time of lighting which one it takes? voltage or current

6 Answers  

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what is the difference betn earthed and unearthed cables which is commanly used why?

2 Answers   Bhel, Power Grid,

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sir i completed apprentice in TNEB.apprentice is eligible for 'c' licence

0 Answers   Bhel, TNEB Tamil Nadu Electricity Board,

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