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Section 3 Controls and Indicators
Pictures of the display and controls are shown at the rear of this manual.
3.1
Bargraph and exponent
The bargraph and exponent indicate the leak
rate in terms of the selected units. For
example, a leak rate of +6 x10-4 ml/sec would
appear as shown opposite.
3.2 Zero
Operating this button sets the detected value, the display, and audible signal to zero.
3.3 Units
Press
ZERO
and
GAS GROUP
together to step
through the available units of measure to set the one
desired. The correspondence between leak rate
settings depends on the sample flow rate. If accurate measurements are required the
instrument should be calibrated in the same mode as it will be used.
3.4 Peak
hold
Press
PEAK HOLD
to select and display the Peak Hold symbol on the screen. In this
mode, the instrument shows the highest positive, or negative, value measured since the
mode was entered. Press
PEAK HOLD
again to exit this mode. The audible leak
indication remains unaffected.
3.5 Gas group button
Use this button to see and select the required gas group.
Upon pressing the button, the display will blank except for the
Leak Rate Exponent which shows the current gas group.
After two seconds, the displayed number will start to cycle
through the gas groups 1 to 4.
To keep the current gas group, press the button again immediately. To select a
different gas group, press the button again when the required group number is visible.
The gas groups, and thermal conductivities, are listed in Section 8.
INT-0124-XX 7