Teledyne 6000A - Photometric analyzer - Manual (Page 41)

Photometric Analyzer Operation 3
Part I 3-17 Teledyne Analytical Instruments
####.## % SO2
4 Left=#.### S—Zero
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 mode.
3.4.1.2 Manual Mode Zeroing
Press Zero to enter the Zero function. The screen that appears allows you
to select between automatic or manual zero calibration. Use the
∆∇ keys to
toggle between
AUTO and MAN zero settling. Stop when MANUAL appears,
blinking, on the display.
Select zero
mode: MANUAL
Press Enter to begin the zero calibration. After a few seconds the first of
three zeroing screens appears. The number in the upper left hand corner is the
first-stage zero offset. The microprocessor samples the output at a predeter-
mined rate.
####.## % SO2
Zero adj:2048 C—Zero
The analyzer goes through C–Zero, F–Zero, and S–Zero. During C–Zero
and F–Zero, use the
∆∆∆∆∆∇ keys to adjust displayed Zero adj: value as close as
possible to zero. Then, press Enter .
S–Zero starts. During S–Zero, the Microcontroller takes control as in Auto
Mode Zeroing, above. It calculates the differences between successive sam-
plings and displays the rate of change as
Slope= a value in parts per million per
second (ppm/s).
####.## % SO2
Slope=#.### S—Zero
Generally, you have a good zero when
Slope is less than 0.05 ppm/s for
about 30 seconds.
Once zero settling completes, the information is stored in the analyzer’s
memory, and the instrument automatically returns to the Analyze mode.