Hioki FT6031-50, Инструкция по эксплуатации

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53
Simplified Measurement for Earth Resistance
(Simplified Measurement Method, 2-pole Method)
Removing and attaching the sleeves of L9787 Test Lead
CAUTION
The tips of the metal pins are sharp and may cause injury.
Do not touch the tips.
• 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 firmly push them all the way in.
What is simplified measurement method (2-pole method)?
Simplified measurement method (2-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 object under measurement 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 object under measurement.
In the simplified measurement method, the resistance of the earthing element
used is added to the measurement result.
It is very difficult to measure 10
Ω
or less in the simplified method
HIOKI FT6031B961-00