GEOHM 5
Introduction
5
1.3 General settings (first use)
There is usually voltage or current noise present on the earthing system under test,
caused by mains voltage somewhere in the near or far vicinity. Mains voltage frequency
is different in different countries (50 Hz in European countries etc., 60 Hz in the United
States etc.). In order to get stable test results, regardless of noise levels, it is advisable
to insert the nominal frequency of the mains system.
The instrument’s measuring system assures excellent noise immunity. In extremely
noisy conditions, the stability of results can be further improved by means of averaging.
The frequency and algorithm, once set, will stay set, even after replacing batteries.
Insert the frequency of mains voltage (50/60 Hz)
Setting the unit of Specific Earth Resistance parameter (
m/
ft)
Setting the measuring algorithm
Switch
OFF
the instrument.
Keep
ON
key pressed while switching on the instrument until
Fr
followed by
50
or
60
value (last selected) starts to flash.
Hz
Press
UP/DOWN
key to select appropriate frequency of mains
voltage.
Press
START
key to confirm “Frequency”. Unit
m
or
ft
(last
selected), used in Earth Resistivity measurement, starts to flash.
m
Select appropriate unit (
m
or
ft
).
Press
START
key to confirm “Unit selection”. Measuring algorithm
type starts to flash.
Normal algorithm
Improved
noise
rejection
algorithm (by means of averaging
tehniques)