Teledyne 7300A, Operating Instructions Manual

Page: 53 / 85

Infrared Gas Analyzer Operation 4
4-17 Teledyne Analytical Instruments
If you want to calibrate ALL of the ranges at once
(multiple application analyzers only), use auto mode
zeroing in the Cal Range.
Make sure the zero gas is flowing to the instrument. If you get a
CELL
CANNOT BE BALANCED
message while zeroing skip to section 4.4.1.3.
4.4.1.1 Auto Mode Zeroing
Observe the precautions in sections 4.4 and 4.4.1, above.Scroll to ZERO
function buy using UP/DOWN control and enter the zero function mode. The
screen allows you to select whether the zero calibration is to be performed
automatically or manually. Use the UP/DOWN key to toggle between
AUTO
and
MAN
zero settling. Stop when
AUTO
appears, blinking, on the display.
Select zero
mode: AUTO
Press Enter to begin zeroing.
####.## % CO2
Slope=#.### C—Zero
The beginning zero level is shown in the upper left corner of the display. As
the zero reading settles, the screen displays and updates information on
Slope=
in
ppm/second (unless the Slope starts within the acceptable zero range and does
not need to settle further). The system first does a course zero, shown in the
lower right corner of the screen as
C—Zero
, for approximate 3 min, and then does
a fine zero, and displays
F—Zero
, for approximate 3 min.
Then, and whenever Slope is less than 0.01 for at least 3 min, instead of
Slope you will see a countdown:
9 Left
,
8 Left
, and so fourth. These are software
steps in the zeroing process that the system must complete, AFTER settling,
before it can go back to
Analyze . Software zero is indicated by
S–Zero
in the
lower right corner.
####.## % CO2
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.