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Do you know how to measure the earth resistance? if so
explain it
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Answer Posted / s. ghosh
earth resistivity is measured by earh megger . there so
many methods of earth resistivity measurements like1)
wenner 4 pin method, 2) schlumberger method, 3) driven rod
or 3pin method. all those test results varies on different
parameters of the site. to minimise tose effects the tests
has to be performed in an arrey called"line traverse
servay". the detail of those above methos i.e. the distace
of rod depth of rod and their variation is to be discussed
in detail. however the result given by the "earth megger"
i.e. the resistance of earth is to be converted into earth
resistivity by the following formula.
Wenner method:-
r(resistivity) = 2(PI)A R : A =Probe spacing, R
resistance reading in the E/megger
Schlumberger:-
r=(PI) L.L.R/2.l L=centre limb to outer probe,
l=centre limb to inner probe,
Driven rod:-
r=2(PI)lR/Ln(8l/d) l=rod length in earth, d=dia of rod.
contact me at sgmanofpower@yahoo.com if you have got
further details or questions.
| Is This Answer Correct ? | 12 Yes | 10 No |
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