Answer / kishore

DUE TO MAGNETOSTRICTION IT HAPPENS COZ WHEN FERROMAGNETIC
MAG TRANF CORE IS MAGNETISED THE CORE LENGTH ALTERNATIVELY
INC N DECR N HENCE TRANSFORMER CORE DIMENS INC N DECR
SLIGHTLY
HIGHER THE CORE FLUX HIGHER IS THE HUMMING NOICE N IT
DEPENDS ON NATURE OF CORE CONSTRUCTION N CLAMPINMG

Answer / rajesh tokalapudi

This is mainly due to magnetostriction.means whenever a
ferro magnetic material is subjected to magnetism its
dimenstions will change.this will results in some noise.

Answer / sureshreddy gummadi

DUE TO MAGNETOSTRICTION IT HAPPENS COZ WHEN FERROMAGNETIC
MAG TRANF CORE IS MAGNETISED THE CORE LENGTH ALTERNATIVELY
INC N DECR N HENCE TRANSFORMER CORE DIMENS INC N DECR
SLIGHTLY
HIGHER THE CORE FLUX HIGHER IS THE HUMMING NOICE N IT
DEPENDS ON NATURE OF CORE CONSTRUCTION N CLAMPINMG

Answer / banamali mohanta

Humming noise in transformer is due to MAGNETOSTRICTION
which causes change in length of core as per the density of
flux

Answer / pavan

When we supply ac volatage to the the ferrite material there
is change in its length this process is called
magnetostriction.The core of the transformer is made of
ferrite material so that when voltage is flowing through
transformer a change occurs at runtime due to this a humming
noise will be produced on the transformer.

Answer / suhani

Magnetic flux in a ferromagnetic material, such as the core,
causes it to physically expand and contract slightly with
each cycle of the magnetic field, an effect known as
magnetostriction. This produces the buzzing sound commonly
associated with transformers, and in turn causes losses due
to frictional heating in susceptible cores

Answer / siddesh cs

It mainly happens when inductive loads are connected to transformer. inductive load which will produce harmonics so t/c produce noise.

Answer / mahendra sonsare

Due to eddy current loss and laminated core was not press
fit and insulated from one to another due to air gap the
sound occurs.

Answer / sethar12

Transformer noise is mostly due to third harmonic.

Answer / abid ali khattak

due to the eddy current losses. Because whenever we provide
the power supply to the transformer emmidiatly flux run in
the core.hence due to the silicone immitted core the
insulation between one layer to another layer is becomes
lettle and the fulx will go high which is becomes vibration
and giving the noise. Which we can observed nearby the
transformer.

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