Fluke Fluke 4325162 User Manual

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This instrument is equipped with a 3-pole as well as a 4-pole resistance measurement 
that renders measurements of resistances of earthing systems possible, as well as 
measurements of the soil resistivity of geological strata. A specific description of the 
different applications is given further on in this manual. As a special function, the 
instrument offers measurements with an external current transformer, with which a 
measurement of single resistance branches in interlinked networks (lightning protection 
and high voltage pylons with cabling) can be performed without separating parts of the 
system. See Figure 3. 

To ensure most feasible interference suppression during measurements, the instrument 
is equipped with four measuring frequencies (94 Hz, 105 Hz, 111 Hz, 128 Hz), with 
automatic switch over if necessary (AFC - Automatic Frequency Control). The 
corresponding measuring frequency used for a specific measurement can be called and 
displayed with DISPLAY MENU after the measurement. Additionally, one of the four 
measuring frequencies can be selected and permanently set in special cases. In that 
case, in order to stabilize the display, an average measurement can be carried out for up 
to 1 minute by keeping the START TEST button pressed. 

To determine the earthing impedance (R*) a measurement with a frequency close to the 
mains frequency (55 Hz) is carried out. At the activation of R* through user's code, this 
measuring frequency is activated automatically. 

To keep the instrument as simple as possible at the time of delivery, all special functions, 
such as LIMIT input, BEEPER programming, and measurement of earthing impedance 
(R*) are not activated at delivery. They can be activated with personalized user's code 
(see How to Change All Data Settings with Personalized CODE). 

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