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(5) Measured resistances at simplified measurements
Two-Wire method is used for the simplified measurements. In this
method, earth resistance of the earthed electrode (re) connected to the
S(P) Terminal is added to the true earth resistance Rx and shown as
an indicated value Re .
Re (indicated value) = Rx + re
If the Re is known beforehand, true earth resistance value Rx is
calculated as follows.
Rx = Re -re
Note) The re cannot be canceled by the setting of Rk.
9-2 Earth Resistivity (ρ) Measurement
#
CAUTION
● The measured results may be influenced by induction if measure-ments
are made with the Test Leads twisted or in touch with each other.
When connecting the Probes, they should be separated.
Making a setting of the interval between Auxiliary Earth Spikes first and
measuring the earth resistances with the 4 Auxiliary Earth Spikes stuck into
the ground at even intervals. Then the instrument can calculate and display
earth resistivity on the LCD automatically.
Terminals to be used : E, ES, S(P), H(C) Terminals
Test Leads
: connect to the E, ES, S(P) and H(C) Terminals
Auxiliary Earth Spike : 4 pcs
(1) Setting of Wiring System
Select Wire (ρ) with reference to
8-2-2 Setting for Measurement
Method
in this manual.
Note) The instrument doesn't accept any setting change on Rk while
measuring earth resistivity (ρ).
(2) Connection of Auxiliary Earth Spikes and Test Leads
Stick the four Auxiliary Earth Spikes into the ground deeply. They should
be aligned at an interval of 1-30m. The depth should be 5% or less of
the interval between the spikes.
