Teledyne 6020 - Photometric analyzer - Manual (Page 42)

3 Operation Model 6020
3-18 Part I
Teledyne Analytical Instruments
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
Enter the Zero function. The screen that appears allows you to select
between automatic or manual zero calibration. Use the UP/DOWN switch
between
AUTO and MAN zero settling. Stop when MANUAL appears, blinking,
on the display.
: : : : :
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 predetermined
rate.
####.## ####.## ####.## ####.## ####.##
:2048 С :2048 С :2048 С :2048 С :2048 С
The analyzer goes through C–Zero, F–Zero, and S–Zero. During C–Zero
and F–Zero, use the UP/DOWN
SWITCH
to adjust displayed Zero adj: value
as close as possible to zero. Then, 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).
####.## ####.## ####.## ####.## ####.##
=#.### С =#.### С =#.### С =#.### С =#.### С
Once zero settling completes, the information is stored in the analyzer’s
memory, and the instrument automatically returns to the Analyze mode.
3.4.1.3 Detector Failure
Detector failure in the 6020 is usually associated with inability to zero the
instrument with a reasonable voltage differential between the reference and
measure voltages. If this should ever happen, the 6020 system alarm trips, and
the LCD displays a failure message.