Answer / bharath kumar

TRANSFORMERS WORKS ON THE PRINCIPLE OF MUTUAL INDUCTION
WHICH IS A PURELY AC PHENOMENON,HENCE WORKS ONLY FOR AC
SUPPLY NOT FOR DC

Answer / wareagle

Is there a question. Transformers do not use a DC supply.

Answer / kj

Induction requires a conductor to move through a magnetic
field.

In a transformer the conductor is stationary and the
magnetic field is moved by the rise and fall of voltage
from the sine wave. This requires a change in voltage. With
DC the only change would be when it is turned on and turned
off. So pure DC will not work with a transformer.

The second thing is that with AC there will be a winding
resistance and an impedence as well to limit the current
flow. With DC there will only be winding resistance. This
could cause the windings to over heat if the same voltage
is applied.

Answer / avi2neha

There will be dead short circuit. due to dead short circuit transformer will get burn due to over heating of transformer winding.

A 400KVA transformer has 400 Hz frequency. If the frequency is changed to 50 Hz, then what will be the new KVA rating?

0 Answers   Spectrum,

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what is the formula for 3 phase motor starting cureent deatials 3phase 148A delta 415v, efficiancy 94% can we run the motor with 200A incoming supply

2 Answers  

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Can the output voltage of a rectifier be greater than the input AC voltage without the use of any voltage multiplier in the circuit??please provide the explanation too..

0 Answers   IOCL,

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I have a 5KVA UPS. Total load to be connected almost 3KW. Ordering a battery pack with capacity of 1920VAh. How long will the backup time be?

1 Answers  

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HT/LT PANEL TEST?ALL TEST

0 Answers  

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how to check dc current,how to fix ammeter in dc line

5 Answers   Gold Fields,

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5 Answers  

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Why the design of electromechanical energy conversion machines is based on the medium of conversion as megnetic field not as electric field?

2 Answers  

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I know during Surge Impedance Loading maximum power is transferred through a transmission line and also Sending end voltage becomes equal to Receiving end voltage i.e Vs=Vr so my question is if both end voltages are equal then how current travels in such line hence how power is transmitted because flow of current needs Potential difference??

3 Answers   NTPC,

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is earthing is necessary if we use armoured cable

1 Answers   ABB, Schwing Stetter, Siemens,

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Suppose a 3 phase, 2 pole, 440V induction motor is driving a flywheel of 600mm diameter, 150kg mass. By using v-belt and pulley, the speed is increased to 4500 RPM. What will be the effect on motor current?

0 Answers  

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what is the meaning of spur line?

1 Answers  

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