Teledyne Analytical Instruments 3020 M, Operating Instructions Manual

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Operation Model 3020M-ATEX
Teledyne Analytical Instruments 50
#### PPM Zero
1 Left=### ppm/s
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.
4.8.1.2 M
ANUAL
M
ODE
Z
EROING
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
MAN
appears, blinking, on the display.
Zero: Settling: Man
<ENT> To Begin
Select
Enter
to begin the zero calibration. After a few seconds the
first of five 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. It calculates the differences between
successive samplings and displays the rate of change as
Slope=
a value
in parts per million per second (ppm/s).
#### ppm Zero
Slope=#### ppm/s
Note: It takes several seconds for the true Slope value to display.
Wait about 10 seconds. Then, wait until Slope is
sufficiently close to zero before pressing Enter to finish
zeroing.
Generally, you have a good zero when Slope is less than 0.05
ppm/s for about 30 seconds. When Slope is close enough to zero, select
Enter
. In a few seconds, the screen will update.