ETCR 3000B, Руководство пользователя

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like commercial use power system.
Then, the earth ground resistance value of measured earthing object
is: RX=R
－
re
8
．
Soil Resistivity Measurement
Soil resistivity ρ is a determining factor of earthing resistance of
earthing body. Different nature of the soil, there is a different soil
resistivity. Even the same kind of soil, due to different temperature and
water content and so on, the soil resistivity will correspondingly have a
significant change. Therefore, in order to have a correct basis in the
design of the earthing device, ensure the designed earthing device be
more in accord with the need of practical work, soil resistivity
measurement is very essential.
Soil resistivity is measured by 4-pole method (Wenner method)
According to formula ρ=2πaR(Ωm) calculating soil resistivity ρ , its
unit is Ωm , in which:
a ——electrode distance
R ——soil resistivity between electrode P
(S)-
ES
4-pole method (Wenner method): Connect testing wires as shown
below, pay attention to the distance between auxiliary earthing rods, and
the embedding depth. Respectively insert C
(H)
, P
(S)
, ES , E auxiliary
earthing rods deep into the earth in a straight line, and then connect
testing wires (red, yellow, green, black) corresponding to C(H) , P(S) , ES ,
E of interfaces and measured auxiliary earthing rods.
Setting distance between auxiliary earthing rods: After finishing
wires connection, firstly rotate
FUNCTION
rotary switch to “
ρ
EARTH
”,
long press “ SET ” button (about 3 seconds) to enter setting, short
press “
SET
” button to move the cursor, press “ ”or “ ” button
to change current data value ( a range:1m-100m), then long press
“ SET ” button to save the set a value, and return soil resistivity testing
Red Yellow Greed Black