Sib Geofiz Pribor Ltd
press the START-STOP button, after which the “Tests sequence” dialogue menu will be
displayed again.
4.4.3.2. Noise
This parameter can take values 0 (Off) and from 1 to 100 mV. The parameter value can
be changed both by the use of LEFT and RIGHT arrows and by entering a number. On
entering 0, the parameter takes the “Off” value. The number specifies the maximum
permissible (for normal testing) value in millivolts. The higher is noise at the geophone
location, the less reliable are test results. Generally, the 5 mV threshold (root-mean-
square) is acceptable.
Pressing the START-STOP button can start continuous performance of the noise test
without writing results into memory. Numerical values and a histogram of root-mean-
square and peak values of noise are continuously displayed on the screen (see Fig. 10).
To terminate the test, press the START-STOP button, after which the “Tests sequence”
dialogue menu will be displayed again.
Figure 10
4.4.3.3. Leakage
This parameter can take values 0 (Off) and from 1 to 100 MΩ. The parameter value can
be changed both by the use of LEFT and RIGHT arrows and by entering a number. On
entering 0, the parameter takes the “Off” value. The number specifies the minimum
permissible value of leakage resistance in megohms. Leakage resistance is measured
between one of the geophone string poles and the “earth”, i.e. conducting surface
connected to the housings of geophones. To measure leakages, contact 5 of the Tester
“GEOPHONE” connector should be connected to the “earth”. This contact is connected
with grounding probe of the geophone cable included in Tester kit.
Pressing the START-STOP button can start continuous performance of the test group
including the resistance test, the impedance test and the leakage test, without writing
results into memory. Tests are conducted sequentially, one after another, in a ring. The
results of
enabled tests only
are displayed (see Fig. 11).
Figure 11
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