Hioki FT3151 - Measuring Earth Resistance Precisely (Precise Measurement, 3-Pole Measurement Method)

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Measuring Earth Resistance Precisely
(Precise Measurement, 3-Pole Measurement Method)
2.2 Measuring Earth Resistance
Precisely (Precise Measurement,
3-Pole Measurement Method)
WARNING
This instrument can output a voltage of approx. 50 V.
The instrument must always be dried before using it
for measurement to avoid an electric shock.
CAUTION
Do not connect the test leads if any foreign material
remains inside. It may cause failure.
There are two types of measurement method for earth resistance:
precision measurement method (3-pole method) and simplied
measurement method (2-pole method). The precision measurement
method (3-pole method) is the basic measurement method for earth
resistance.
The simplied measurement method is used when measurement
cannot be performed by the precision measurement method.
The precision measurement is performed by inserting two auxiliary
earthing rods into the ground as shown in the gure on p. 28.
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Appx. Ind.