Teledyne 4020 - Hydrocarbon analyzer - Manual (Page 77)

Total Hydrocarbon Analyzer Operation
Teledyne Analytical Instruments 61
4.6.16.3 D EFAULT (B Y F UNCTION )
In the default mode of valve selection, the specific valve that is open
to the analyzer depends on whether the analyzer is in Analysis mode or
is in a calibration mode. If it is in Analysis mode, the “SAMPLE” valve
is open to the analyzer. If it is in a calibration mode then either the
“SPAN” or ZERO” valve will be open to the analyzer.
To switch to the default mode of valve operation:
<▲▼> From the VALVE SELECTIONS menu, Use the <▲▼>
keys to toggle the option to default
<Enter> Press <Enter> to bring up the valve selection default
screen.
▲▼> Use the <▲▼> keys to toggle to the “DEFAULT”
option.
<Enter> Press <Enter> when “DEFAULT” is displayed on screen.
<Escape> Use Escape to move back to the Analyze Mode. Note that
the analyzer will now switch either sample or calibration
gas (zero or span) to the analyzer depending on the
function of the analyzer, whether it is analyzing a sample
gas or calibrating.
During analysis, the screen will display as: