Purpose
To describe the procedure for Earth pit testing | Ground Testing .
Procedure:
The earthing value of an earth pit can be tested with
the help of Digital or manual Megger.
Testing with
Manual Megger:
In Manual Megger machine there are three knobs of
Phase, Earth and Common,
Connect the Common knob to the Earth pit and Phase and
earth in two separate locations Meter away (In Triangle) from the Pit under
test.
Now rotate the machine handle in clockwise direction,
after rotating the machine
handle the megger dial indicator starts showing value.
Rotate the machine handle until the dial indicator get stable in single value.
The Earthing Pit Value Should Not be more than 2 Ω, If the
value of earthing
resistance is more than 2 Ω then
charge the Earth Pit with mixture of salt and water.
Testing with Digital Megger
The earthing pit value can also be measure with the
help of Digital Megger, in this
case simply clamp the digital megger to pit, the
digital meter shows the value in megger, if the value of Earthing resistance
found more than 2 Ω then follow the process mentioned in
The frequency of Earth pit testing shall be Half
Yearly.
