Teledyne 3000TB, Operating Instructions Manual

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Operation 3000TB
Teledyne Analytical Instruments 58
Note: When performing analysis on a fixed range, if the oxygen
concentration rises above the upper limit (or default value)
as established by the operator for that particular range, the
output saturates at 1 VDC (or 20 mA). However, the digital
readout and the RS-232 output continue to read the true
value of the oxygen concentration regardless of the analog
output range.
4.7 The Analyze Function
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
Analyze function when they have completed their assigned operations.
Pressing the Escape button in many cases also switches the analyzer
back to the
Analyze
function. Alternatively, you can press the
Analyze
button at any time to return to analyzing your sample.
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 concentrations. 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
analyzer or somewhere within the users
sample system.
4.8 Maintenance Schedule
The Maintenance function offers the user the ability to set a screen
notification after a user-defined period that the sensor needs replacement.
For instance, after installing a new sensor, the user can set a defined