Hioki FT6031 - Performing Zero Adjustment

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Simplied Measurement for Earth Resistance
(Simplied Measurement Method, Two-pole Method)
Removing and attaching the sleeves of L9787 Test lead
• Removing the sleeves
Hold the bottom of the sleeves and pull the sleeves off.
Safely store the removed sleeves so as not to lose them.
• Attaching the sleeves
Insert the metal pins of the test leads into the holes of the
sleeves, and rmly push them all the way in.
What is simplied measurement method (two-pole method)?
Simplied measurement method (two-pole method) is a measurement
method to check the earth resistance of the equipment earthing with an earth
system called TT method.
In case of not being able to insert an auxiliary earthing rod, the earth
resistance is obtained with use of an existing low earthing resistor as an
auxiliary electrode.
In this method, the measured value is the sum (Rx+Ro) of the earth
resistances of the measuring object and existing earthing resistor,
according to the measurement principle. Therefore, the earth resistance
of the existing earthing resistor used needs to be lower than that of the
earthing electrode of the measuring object.
In the simplied measurement method, the resistance of the earthing
element used is added to the measurement result.
It is very difcult to measure 10
Ω
or less in the simplied method.
Performing zero adjustment
The range that this device can provide zero adjustment for is 3
Ω
or less. If
the measured value exceeds 3
Ω
, [Err 1] appears and zero adjustment will
not be executed.