Teledyne 3020T - Manual (Page 49)

Trace Oxygen Analyzer Operation 4
4-13 Teledyne Analytical Instruments
typing in the concentration of the span gas you are using, repeatedly select
ENTER until the rightmost digit is reached, then, the next ENTER will exit the
Span Val field. One more ENTER will enter the new span value, bring up the
next screen, and start the span calibration.
#### ppm Span
Slope=#### ppm/s
The beginning span value is shown in the upper left corner of the
display. As the span reading settles, the screen displays and updates informa-
tion on
Slope. Spanning automatically ends when the span output corre-
sponds, within tolerance, to the value of the span gas concentration. Then the
instrument automatically returns to the ANALYZE mode.
4.8.2.2 Manual Mode Spanning
ENTER SPAN from the MAIN MENU to start the SPAN function.
The screen that appears allows you to select whether the span calibration is
to be performed automatically or manually.
Span: Settling:MAN
<ENT> For Next
Use DOWN/UP to toggle between
AUTO and MAN span settling. Stop
when
MAN appears on the display. Use ENTER to move to the next screen.
Span Val: 209000.00
<ENT>Span <UP>Mod #
Use UP to permit modification (
Mod #) of span value.
Use ESCAPE/ENTER to choose the digit, and use DOWN/UP to
choose the value of the digit.
When you have finished typing in the concentration of the span gas you
are using, repeatedly select ENTER until the rightmost digit is reached, then, the
next ENTER will exit the Span Val field. One more ENTER will enter the new
span value, bring up the next screen, and start the span calibration.
Once the span has begun, the microprocessor samples the output at a
predetermined rate. It calculates the difference between successive samplings
and displays this difference as Slope on the screen. It takes several seconds
for the first Slope value to display. Slope indicates rate of change of the Span
reading. It is a sensitive indicator of stability.
#### % Span
Slope=#### ppm/s