4. Measuring Methods
1. Before proceeding with measurement, if "
" symbol appears on
the display, replace with new batteries.
2. Rotate the function switch to the "Earth voltage" position and press
to test. Earth voltage will be displayed on the LCD. When the earth
voltage is more than 10 V, it may result in errors in earth re-
sistance measurement. Accurate earth resistance measurement
may not be made.
3. Precision earth resistance measurement method:
(1) Connect green, yellow and red test leads to instrument termi-
nals E, P and C with auxiliary earth spikes P1, C1 inserted into
earth "IN A STRAIGHT LINE". (Fig. 1)
(2) Rotate the function switch to the proper range, then press the
push-button to test and take the reading.
Fig. 1
4. Simplified earth resistance measurement method:
(1) This method is recommended where an earth resistance higher
than 10
Ω
is measured or where it is not possible to drive aux-
iliary earth spikes. An approx. value of earth resistance can be
obtained by the two-wire system as shown in Fig. 2
(2) Rotate the function switch to the "Earth Voltage" position and
press to test. Make certain that earth voltage is less than 10 V.
(3) First rotate the function switch to "200
Ω
" position and press to
test. Read earth resistance. If the display shows "1" (MSD),
switch to "2000
Ω
" and read earth resistance.
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