Teledyne 3020T - Manual (Page 55)

Trace Oxygen Analyzer Operation 4
4-19 Teledyne Analytical Instruments
4.13 The Analysis Mode
This is the normal operating mode of the analyzer. In this mode the
analyzer is monitoring the sample, measuring and displaying the amount of
oxygen, and reporting alarm conditions.
Normally, all of the functions automatically switch back to the Analysis
Mode ANALYZE screen when they have completed their assigned opera-
tions. After four or five minutes in the MAIN MENU without any action by
the operator, the analyzer automatically switches itself back to the ANA-
LYZE screen. ESCAPE, asserted one or more times, depending on the
starting point, also switches the analyzer back to the ANALYZE screen.
IMPORTANT: In the event of loss of flow through the analyzer, if the
vent is vented to a location of high oxygen content,
oxygen will back diffuse through the vent line and in
most cases quickly saturate the cell with oxygen which
can then require a quite long purge down time for the
sensor when then exposed to low oxygen concentra-
tions. In the event that flow is to be interrupted into the
analyzer, it is suggested that the user do one of the
following:
1. Bag the sensor in nitrogen during this time
2. Install a shut off valve on the vent port of the ana-
lyzer or somewhere within the users sample system.