Teledyne 3020M Operating Instructions Manual page 63

Percent Paramagnetic Oxygen Analyzer
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The ZERO function on the MAIN MENU is used to enter the zero
calibration function. Zero calibration can be performed in either the auto-
matic or manual mode. In the automatic mode, an internal algorithm com-
pares consecutive readings from the sensor to determine when the output is
within the acceptable range for zero. In the manual mode, the operator
determines when the reading is within the acceptable range for zero.
Make sure the zero gas is connected to the instrument.
If you have trouble zeroing, you may need to skip to section 4.8.1.3
Cell Failure.
Select ZERO to enter the ZERO function. The ZERO screen allows
you to select whether the zero calibration is to be performed automatically or
manually. Use the DOWN/UP control to toggle between AUTO and MAN
zero settling. Stop when AUTO appears on the display.
ENTER to begin zeroing.
The beginning zero level is shown in the upper left corner of the dis-
play. As the zero reading settles, the screen displays and updates information
on Slope (unless the Slope starts within the acceptable zero range and does
not need to settle further).
Then, and whenever Slope is less than 0.08 for at least 3 minutes,
instead of Slope you will see a countdown, such as 1 Left, 0 Left. These are
steps in the zeroing process that the system must complete, AFTER settling,
before it can go back to ANALYZE.
The zeroing process will automatically conclude when the output is
within the acceptable range for a good zero. Then the analyzer automatically
returns to the ANALYZE screen.
Zero Cal
Auto Mode Zeroing
Zero: Settling: AUTO
<ENT> To Begin
####
Slope=####
####
1 Left=###
Teledyne Analytical Instruments
% Zero
ppm/s
% Zero
ppm/s
Appendix
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