Sib Geofiz Pribor Ltd
The permissible limits of each parameter variation recalculated having regard to the
specified string configuration and ambient temperature are displayed in square brackets
for reference use. In this case, [0.640-0.782] means that the damping should be no less
than 0.640 and no more than 0.782. To terminate the test, press the START-STOP
button, after which the “Tests sequence” dialogue menu will be displayed again.
4.4.3.7. Sensitivity
This parameter can take values “Off” and “On”. The parameter value can be changed
using the LEFT and RIGHT arrows.
Pressing the START-STOP button can start continuous performance of the test group
including the natural frequency test, the damping test and the sensitivity 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. 12).
The permissible limits of each parameter variation recalculated having regard to the
specified string configuration and ambient temperature are displayed in square brackets
for reference use. In this case, [18.1-22.1] means that sensitivity should be no less than
18.1 and no more than 22.1 V / (m/s). To terminate the test, press the START-STOP
button, after which the “Tests sequence” dialogue menu will be displayed again.
4.4.3.8. Distortion
This parameter can take values 0 (Off), 1 (On) and from 2 to 79 Hz. 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, and on entering 1—the
“On” value. A number from 2 to 79 specifies the frequency at which the harmonic
distortion will be measured. When the parameter equals 1 (On), distortion will be
measured at the frequency specified by the geophone manufacturer. This frequency is
contained in the Tester libraries.
Pressing the START-STOP button can start continuous performance of the distortion
test without writing results into memory. The values of measurement frequency in Hz,
the total harmonic distortion (THD) and harmonics with numbers 2, 3, 4, 5 are
continuously displayed on the screen (see Fig. 13).
Figure 13
The maximum permissible THD value for a selected geophone type is displayed in
square brackets for reference use. In this case, [<0.20] means that THD should not
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