Answer / n k singh

As we know transformer is a static device and as per
Faradays law of electromagnetic induction the voltage in
the seconary will be induced if flux produced by primary is
changing with time. If primary is fed with DC then there is
no d/dt(of flux),so no emf will be induced in secondary.

Answer / santosh kumar garnayak

when dc will be applied to transformer,as inductor will be
short circited(in dc f=0 so xl=2*pi*f*l=0) so net resistance
(I=V/(R+XL)=V/R ) will decrease and high amount of current
will flow which will result in damage to the transformer`

Answer / satyapal prajapati

when ac is applied on the t/f primary there is change in
flux in primary. due to this change in flux an emf induced
in the primary which opposes the applied voltage according
to lenz's law called back emf.
but when we apply dc to the primary there is no flux
change and no back emf. the applied voltage damage the
primary winding of t/f. and there is no voltage in the
secondry.

Answer / aditya

WE KNOW THE PRINCIPLE OF TRANSFORMER THAT EMF WILL INDUCE IN
SECONDARY WHEN EVER FLUX CHANGES W.R.T TIME, NOW WHEN WE
GIVE D.C TO T/F THAN THERE IS NO VOLTAGE INDUCE IN SECONDARY
SIDE DUE TO WHICH PRESSURE ON THE PRIMARY SIDE INCRESES(IN
A.C AS IT IS LIKE PRESSURE COOKER AS PRESSURE INCREASES IT
WILL RELEASE BY MUTUAL INDUCTION IN SECONDARY SIDE BUT IN
D.C THERE IS NO INDUCTION)SO THE WINDINGS OF TRANSFORMER MAY
BURNS OUT.

Answer / s k singh

transformer burns

Answer / sasi karthick a

Inductive reactance is zero since F=0; high current pass
thru', windings may damage/burn. And ofcource no mutual
induction.

Answer / k.prakashchandra

As there is no back e.m.f ( opposing voltage ) the magnitude of current depends on dc resistance ( R ) of the windings and voltage

A power transformer 4MVA/11KV/0.415Kv has been out of use in 12years. what maintenance actions/test need to be carried out before energizing.

0 Answers  

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A low wet bulb temperature indicates

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