Teledyne 9110T - Nitrogen Oxides Analyzer - Manual (Page 305)

Model 9110T NOx Analyzer Troubleshooting & Service
Teledyne Analytical Instruments 305
Note This is one of the two settings in the DIAG menu that is retained after you
exit the menu.
12.7.16. INTERNAL SPAN GAS GENERATOR AND VALVE OPTIONS
The zero/span valves and Internal span gas generator options need to be enabled in the software (contact
the factory on how to do this).
 Check for the physical presence of the valves or the IZS option.
 Check front panel for correct software configuration. When the instrument is in SAMPLE mode, the
front panel display should show CALS and CALZ buttons in the second line of the display. The
presence of the buttons indicates that the option has been enabled in software. In addition, the IZS
option is enabled if the TEST functions show a parameter named IZS TEMP.
The semi-permeable PTFE membrane of the permeation tube is severely affected by humidity.
Variations in humidity between day and night are usually enough to yield very variable output results. If
the instrument is installed in an air-conditioned shelter, the air is usually dry enough to produce good
results. If the instrument is installed in an environment with variable or high humidity, variations in the