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3
．
The working error (
B
) is the error within the rated operating conditions,
which is calculated from the inherent error (
A
) and variation error (
Ei
) of
the existing instrument.
。
A
：
inherent error
E2
：
Changes due to power supply voltage changes
E3
：
Changes due to temperature changes
E4
：
Changes due to disturbance voltage variations
E5
：
Changes due to contact electrode resistance
4
．
Soil resistivity (
ρ
) is measured using the 4-pole method (Winner
method): AC current I between ground electrode E and
current electrode
H
,calculate the potential difference
V
between the
voltage pole S
and the
auxiliary ground pole ES
,the potential difference
V
is divided by the
alternating current
I
to obtain the ground resistance value
R
, the electrode
spacing distance is
a(m)
，
according to the formula
ρ
=2
π
aR(
Ω
m)
, the soil
resistivity value is obtained, when the distance between
H-S
and
S-ES
is equal
(both
a
), it is the Wenner method. For ease of calculation, please make the
electrode spacing
a
much larger than the buried depth
h
, generally should
meet
a
> 20
h
, see the figure below.
VII
．
Operation
1
．
Switch on/off
Press the POWER button to switch on and off. After turning on the machine,
the lower corner shows "APO" and it will automatically shut down after 15
minutes when it is not operating.
2
．
Battery Voltage Check
Summary of Contents for ES3001
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