Answer / shantanu

the transformer action is not possible with dc of constant
magnitude as the flux will not be genrated btwn primary &
secondary winding ..

Answer / sivakumar

it mean we are applying dc(constant) current to coil ,voltage is zero across inductor(transformer winding) so there is a short circuit occuring so it draws high current

Answer / abhinav kumar

Ac voltage waveform is alternate so genrate a mutual induction and dc is direct current so it is not genrate mutual induction

Answer / bapan

If Dc supply is given to atransformer there will be no change in the flux with time.so,there is no emf induced in the primary and secondary winding and hence transformer action will not take place.

Answer / r. p. siroih

The transformer works on the basis of to transfer the energy (votage) to stepping down or up in alernative mode. In the DC power the current flow in streight line, so transformer can not transfer the voltage .

What are the tests to be conducted in the electrical installations

1 Answers  

what is reactive and active power?why we need power factor correction?

2 Answers  

Why Dyn11 Transformer is selected for distribution transformer?

3 Answers   JK Associates, MSETCL Maharashtra State Electricity Transmission Co Ltd,

assume we are put both df/dt and vector surge relay in same bus the df/dt relay setting is +5 hz an -5HZ. we want operat the vector surge relay before the df/dt how i calculate the setting of the vector surge relay.

1 Answers  

how we calculate electrical load on a building according to area?

0 Answers   HFCL,

what is MFD value in capacitor?I have 201 Kva load & reactive power is 150 Kvar. so how it is calculated?

2 Answers   IIT,

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For polarity test on a 11/3.3kV 2.5MVA delta-star Unit Auxiliary transformer,415V 3-phase supply was applied at the HV. Connection between Aa was made with a 2.5mm cable. As soon as power was switched on the cable caught fire and burnt. This test was then abandoned. It is noteworthy to say that a similar cable was also used in a similar transformer for the same. The cable did not burn and test was successfully completed with good result. What is wrong? Please, help me out.

3 Answers  

what is safety of ups

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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,

why the transmission side of the generating transformer is always star??

5 Answers  

how we can calculate power factor in single phase & three phase ?thank u

0 Answers