28-01-2012, 04:09 PM
MODERN ZINC OXIDE SURGE ARRESTER
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Introduction
The most important matter in a
power system is how to handle a fault condition. In power
system networks we have to maintain the voltage, current
and other network parameters at a specified value .
If an abnormal condition is occurred we
must take precaution against the abnormality to protect
the succeeding elements connected to the network.There
are many modern technique to clear the over voltage
condition due to surge fault .
Surge Arrester
Which conducts High voltage surges
on the power system to the ground
Also called Lightning arrester or
surge diverters
They are connected parallel to the
insulator.
Non-Linear resistors are used for the
construction.
Operation
Surge arrestor conducts Surges around
the protected insulator.
It has high ohmic value under normal
operating condition.
It has low ohmic value during Surges.
It will return back to the high ohmic
value when the surge is dissipated.