Answer / t.sudhakar

1.TO AVOID THE GROWTH OF PLANTS AND GRASS NEAR THE YARD
BECAUSE THIS WILL CREAT THE SHORT CIRCUIT.

2.THE ANIMALS ARE NOT WALKED OVER THE STONE ALSO TO AVOID
THE SHOCK ACCIDENTS
3. KEEP THE MOISTURE ALWAYS BOTTOM OF THE STONE TO REDUCE
THE EARTH RESISTANCE

Answer / amrit

Stones are usally used to reduce the earth resistance.

Answer / ratan soni

If you remember a technical term.......Reflection
coefficient>> ideally it should be = 1 but practically its
between 0.9 and 0.95

Now , earthing grid is laid down in the ground beneath the
soil in the yard. This grid is in the form of rectangle
,triangle,square shaped or trapezoidal shape .....i.e. as
per the space available and resistivity of the soil.

Now the earthing current which flows down into the earth
through the earthing plates into the grid has the tendency
to flow upwards to the surface bcoz the surface resistivity
is less than the ground...this could be dangerous for the
staff working in the yard...so to reflect back this current
back to the earth the stones are being laid down....thus
increasing the resistiviy of the surface.

Answer / abhi

1.to avoid rain water to stand on ground.
2.to prevent the growth of grasses and plants.
3.the most important point to avoid step potential and touch potential to rise.where step potential is potential between persons leg.and touch is potential between persons and energized components (transformer/grid).

Answer / chandu gudipati

in rainy seasons the earths crust resistivity will be
increases due to the water may be combine with soil salts so
to avoid this we can use rocks of 40 mm to reduce the fault
current to flow through the transformer
2) due heavy load of the t/f soil can be loss its stiffness
so we use rocks
3)to prevent leakage of oil to ground nduku anthey jari padi
shock kothey chances unai so adi prevent chayadaniki soil
kana rocks chala better

Answer / bh ki

earth is a huge magnet,
flux leakages occur if there is no insulation between earth and transformer.
so rocks acts like insulator.

Answer / minal verma

To prevent the random flow of oil in transformer yard at
the time of leakage of oil in oil filled tranformer.

Answer / wasif arshad

because the structure of stones is a little bit porous so
they are used to absorb moisture present in air in humid
conditions

Answer / rajendran m

To avoid cross improve

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