Answer / zahid ali

Dear Friend
the R = Pl/A is not used to measure earth resistance. is is
used to measure conductor resistance.
to measure earth resistance. We need an DC power source,
Ampere meter & volt meter & the formula R = V/I
The earth resistance testers are available in market, they
are been used by three leads on connected to the test
object & Current & Potentional probes are conneceted 20 &
10 meters away from object under test.

Answer / ullas

using two methods:
1.fall of potential method
2.earth tester(device)

factors affecting earth resistance are
1. Shape & material of the earth electrode.
2. Depth of the electrode at which they r burried in soil.
3. Specific resistance of the soil surrounding the electrode

(Specific resistance of the soil varies depending on
moisture content in the soil..... varies from 80*10^3ohm-m
to 80*10^6ohm-m)

Answer / ashok mishra

by earth tester

Answer / sandesh

To find the earth resistance we basically need to do the
resistivity test of soil which is symbolized by rho.Now as
per IS we need to have mutual earth resistance below 1 ohm.
so to find the earth resistance for different type of
earthing i.e. plate and pipe we need this resistivity which
vary place to place. for a detailed derivation for both
earthing method and calculation for resistance by one
earthing please refer IS 3043

Answer / niranajn

Bu meggar

Answer / sanjeet

earth resitanse is also measured by meggar

Answer / sumit garg

to mesure the earth resistance we need to find a specipic
constant of the earth soul.
so by using a formula.

R=P(L/A) Ohm
where,
p = Secific gravity constant
L = lenth of Earth
A = Area of Earth.

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