Answer / rahul thakur

Lightning arrester is used to provide path to unwanted excessive currents due to lightning strokes,to the earth which is nearly equivalent to zero potential.
Iron may be used but it will lead to high reluctance path and hence a greater losses like hysteresis loss and eddy current loss.
Cold rolled grain oriented means that if the path of flow of magnetic field is along the rolling direction,minimum reluctance is offered.
phase angle is the angle by which the emf induced in the secondary side lags the current.

Answer / badshah

Lightning Arrestor is to bypass the lightning to earth by
which we can protect the equipments from high voltage of
lightning
Piece of iron can be used as a core but it will cause more
eddy current to flow through the core & more iron
losses..that's why the cores are laminated

Answer / dhiraj

In power system when lightning occures it brings ehv to the
earth which can damge your Power system badly to avoid that
we must use arresters with solidly ground to divert the
lightning path,

If we use Iron as core material the core losses will be
like hell which will make trafos efficiency to very less
and due to that eddy current increase will make heating of
trafo.

for further details read power system engg book.

Answer / deepak

lightning arrestor is a highly pointed device , which can
make the ehv coming from the lightning to split into
positive and negative ions...this ions are absorbed by the
carriers and they are byepassed to the earth ,which is
basically a zero potential.we cannot use iron because eddy
current produced in the iron will be very high .

Answer / guest

protect from Earhing strok

Answer / veer

it is used only for protecting our equipment from the
thunder light. All current bypass through this.

if we use the coil/core then there will be high reluctance
and due to have an rolling iron there will be eddy current
and hysterisis loss

in transformer input is d.c signal which type of emf is induced

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