e) After about five (5) seconds of continuous gas flow, AND WHILE THE GAS IS STILL
FLOWING, press and release the Control Button which will draw a sample of gas into the
unit.
f) When the sample pump completes its cycle (approx. 5 seconds) and the pump light goes
out, release the regulator button to stop the gas flow. IT IS ESSENTIAL THAT THE GAS IS
STILL FLOWING DURING THE ENTIRE 5 SECONDS THE PUMP IS RUNNING!
5) Adjust the Display to the Value of the Dry Gas Standard
With a small screwdriver adjust the appropriate (either the passive (top port) or active (bottom
port) screw) calibration control screw (potentiometer) by inserting the screwdriver in the
appropriate hole on the back of the instrument and turning the control screw clockwise (all the
way up) as the display rises above the value of the dry gas standard. As the display rises still
further, due to the continued charging of the fuel cell, turn the control screw counter clockwise to
set and maintain the display at the dry gas standard value.
As the fuel cell reaches its peak voltage, the control screw will require no further adjusting.
The instrument is now calibrated. Do not turn the control screw to increase the reading once the
display (fuel cell voltage) has passed its peak reading
If the display reading cannot be brought up to the dry gas standard value, the fuel cell has
reached the end of its life and should be replaced.
6) Reset and Wait
After the final alcohol reading is noted, wait 2-5 minutes then depress the sample Control
Button and sample alcohol free air. This clears the fuel cell itself of alcohol before using the
instrument for more tests.
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