Answer / sandeep

Transformer must not be connected to a DC Source because if
the primary winding is connected to DC Supply mains, the
flux produced will not vary but remain constant in magnitude
and therefore no EMF will be induced in secondary winding
except at the moment of switching ON. Also there will be NO
Back EMF induced in the primary winding. Therefore a heavy
current will be drawn from the supply which may result in
the burning of the winding.

In Transformer, If primary winding is connected to a source
of alternating voltage, an alternating flux is set up in the
laminated core and links with the secondary winding of the
transformer in which it produces mutually induced e.m.f
according to the principle Faraday's Laws of
Electromagnetic Induction.

Answer / reji

the above ans is correct. moreover, the DC resistance of T is much less compared to its reactance. ie, impedance is huge . thus when T is connected to DC, a very high current will flow and the winding will certainly burn.

Answer / aravind s

transformer works with mutual induction principle mutual induction must want change of flux or change of conductor.and transformer have non movable parts so we use principle of change of using frequency.

and also transformer works in DC (when it is pulsetting DC)

what is meant by power and distribution transformer ?

0 Answers   CG,

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how step down and step up voltage is occured in transformer

3 Answers  

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1.What is the proper definition of power system stability? 2.some times a blue spark is visible in the secondary side of a distribution transformer at the contact position of bushings and fuse wire,why?

1 Answers  

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iam working as a electrical engineer. i want to know about any license or certificates regarding my field. for my carrier and ti improve the knoweledge.,,, how we get that..and what procedures......... pls help me

1 Answers  

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generally the electrical equipments not to be operated at leading power factor, why?

2 Answers  

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WHY BREAKER ARE USED IN SUBSTATIONS?

0 Answers   Fedco,

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How can we determine or find out the proper size of any cable if nothing is mentioned on it.Calculation of size in Sq.mm???

1 Answers  

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how to test YNyn0 vector group in transformer?

0 Answers  

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In a power conditoining unit (inverter) of a solar plant when we measure the d.c. current fed by different strings of solar plates to inverter, the current in the negative wire is less almost by 1 ampere to the current in its positive wire say current in positive wire 5 A , then current in negative wire of the same string is 4 A. Since the current entering should be equal to current leaving then why the current is noticably less in negative wire.

0 Answers  

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Why strting torqe high in inducation motor?

0 Answers  

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We have a 12MW power plant & we inject 5-6MW power to Orissa GRID. For this we have a 33KV/11KV switch yard having 12.5MVA power transformer. Some times we draw power during emergency. It is observed that during Export or Import for load less than 500Kw the power factor is decreasing to 0.3 . This is happening only during export or import. During island condition TG power factor OK.Our capacitor bank is provided with our Power plant auxilliary load. Please suggest how I can we improve our power factor during low load (GRID).

3 Answers  

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WHY IS THE EARTH FAULT CURRENT ALWAYS LESS THAN THE NORMAL CURRENT??

7 Answers   Reliance,

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