ISA T2000, Руководство пользователя

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DOC. MIE11110 Rev. 5 Page 97 of 110
the soil is homogeneous there will be no change in ? changing d;
instead, if the soil is not homogeneous, for instance some earth
above rocks, ? can change significantly with d.
The resistivity ? is computed by the formula
? = 2 * p * R * d, (Ohm*m)
Where d is in meters and R = V / I is computed from the measured
voltage and the applied current.
For the connection, use the cables and spikes optionally provided.
A) Output connection:
. Two single-pole cables for the connection to the auxiliary
dispersion spike, 10 m long, section 2.5 sq. mm.
. Two auxiliary dispersion spikes, with screw for insertion into the
ground. Complete with connector to the power cable from the
generator. The upper part, that will protrude from the ground, is
isolated with rubber.
. Handle to screw the spike into the ground.
B) Measurement connection:
. Two single-pole cables for the connection to the voltage probes,
10 m long, section 2.5 sq. mm.
. Two test probes to measure the voltage drop; material: zinc-
plated iron; length: 0.5 m. Complete with connector for the
measurement cable.
Once the connection is performed, input the distance between
electrodes, d, then press START and slowly increase the output
current, up to 1 A if possible. If the current is too low, less then
0.1 A, increase the depth of insertion of the auxiliary current
spikes, else the resistivity measurement could be not accurate.
The display shows:
. The test voltage applied between the current spikes;
. The injected current;
. The voltage drop between the two voltage spikes;
. The corresponding soil resistivity.