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what will happen if we give a dc supply to a transformer.?
 Question Submitted By :: Electrical-Engineering
I also faced this Question!!     Answer Posted By  
# 1
transformer windings will burn 
Is This Answer Correct ?    32 Yes 5 No
# 2
transformer induces e.m.f. due to rate of change of flux ,
which is only possible in a.c. supply in stationary
machines, if we will give d.c. supply as input there will
be no out put & due to core saturation after some time it
will be got damaged(burn).
Is This Answer Correct ?    25 Yes 1 No
D.k. Gupta
# 3
transformer works on mutual induction principal & we no
that an ac current change with time due to which flux
generate. if we provide dc to the transformer their is no
linkage of flux to secondary wdg. hense we will not get
anything in secondary or output
Is This Answer Correct ?    18 Yes 2 No
Vedpraksh Uppadhaya
# 4
When Dc supply is given to primary of transformer it draws
heavy current from the DC source due to absence of back emf
and burnt out.Because the dc current not varying with time
it has constant value throught the period.
(AC is given to transformer the sinusoidaly varying
current creates a sinusoidaly varying flux ,this flux cuts
the stationary primary coils and creats a back emf,
(statically induced emf)this back emf opposes the applied
voltage source to drive current(Lenz law) so current is
limited by this back emf hence no overdrawal of current
from source,this is not happen while applying dc)
Is This Answer Correct ?    7 Yes 0 No
Mayilsamy Ranganathan
# 5
ANSWER:Nothing will happen.But fuse will blown off.

EXPLANATION: While applying DC voltage to the
transformer,there is no induced EMF in the primary &
secondary wdg.(except during switching period, both ON&
OFF).so,the transformer will draw high current from the
supply which detoriate the winding insulation & cause
transformer to burn.But actually this will not
happen .Becoz,the fuse will sacrifice itself to protect
transformer from high current.
Is This Answer Correct ?    7 Yes 2 No
# 6
During the time of switching flux links with primary and secondary of the Transformer voltage induced in primary and secondary after that no voltage induced in primary and secondary. Transformer primary take a large current due to the no back emf. This will damage the transformer Primary and later on secondary
Note - If any Correction please send email
Is This Answer Correct ?    2 Yes 0 No
# 7
according to FLEMI change in flux causes EMF induced in the
so when we give a.c change in flux happence, so EMF is
induced in the conductor.
if we give dc[constant flux],so emf induced is zero.
and winding acts as load and dissipates power in the form
of heat and due to over heat winding burns.
Is This Answer Correct ?    1 Yes 0 No
Ramineni Lakshmi Narayana
# 8
for the first time when u give DC to transformer u will get some volt at the o/p for few seconds, after that no volt is transferred to secondary as because of the explanation give above 
Is This Answer Correct ?    3 Yes 3 No
# 9
When DC applied to transformer ,as the dc voltage is not time varying,it produces a constant flux in primary winding,which links only with primary causes primary to burn. 
Is This Answer Correct ?    1 Yes 2 No
# 10
nothing will happen 
Is This Answer Correct ?    7 Yes 28 No

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