Answer / subrat kumar das

Transformer noise is caused by a phenomenon called
magnetostriction. In very simple terms this means that if a
piece of magnetic sheet steel is magnetized it will extend
itself. When the magnetization is taken away. I goes back
to its original condition. A transformer is magnetically
excited by an alternating voltage and current so that it
becomes extended and contracted twice during a full cycle
of magnetization.

Answer / nimish

when A.C. supply is given to ferrite material there is a
change in its length this procedure is known as
magnetostriction and we know that transformer core is
consist of ferrite material and this change in length
causes humming during its running condition.

Answer / niranajn

Is because of humming sound which is an account of
magnetostriction

Answer / nani

Transformer noise is caused by a phenomenon called
magnetostriction. if we r not proporly revited iron
pieces

Answer / amresh marik

this is simply because of magnetostriction...when
A.C.excitation is supplied then due to change in its core
length a pecculier sound produced.

Answer / ajay rastogi

magnetostriction and we know that transformer core is
consist of ferrite material and this change in length
causes humming during its running condition

Answer / karthik

it indicates the oil which is used in tranaformer is less
and is insufficient for the windings

Answer / ravi chandra

transformer noise may be due to,
# Improper core insulation
# aging through continuous running condition which leads to
expansion of core material(Magnetostriction)

Generally if T/F is found noisy at full load conditions and
I think that cannot be avoided but minimized by applying
relevant lubricant over the core.

Answer / akr

DUE TO LAMINATED MAGNETICE CORE HUMING NOISE COMES IN TO
TRANSFORMERS

Answer / sanoj

While under working condition, stress is built up in the
cores and windings of the transformer. Due to these stresses
noise is produced.

Whether should be the oil level in OCTC transfomer? It should be upto winding immersed completely or should be upto tap changer s/w? How it will affect the performance of the transformer. Rating may be 33KVA

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