Teledyne 3000TA-XLEU - Trace oxygen analyzer User Manual
Page 69
Trace Oxygen Analyzer
Operation
Teledyne
Analytical
Instruments
53
Calib. Holding time
Cal hold: 5 min
This menu allows the operator to set the time the analyzer should
be held in the AUTO span mode. It does not have any effect in the
MANual mode. Just press Enter key to continue.
Span Val: 000008.00
Press ▲ (
Mod #
) of span value.
Use the arrow keys to enter the oxygen concentration of the span
gas you are using (209000.00 if you are using air). The ◄► arrows
choose the digit, and the ▲▼
arrows choose the value of the digit.
Press Enter to enter the span value into the system and begin 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 a Slope on the screen. It takes
several seconds for the first Slope value to display. Slope indicates the
rate of change of the Span reading. It is a sensitive indicator of stability.
#### % Span
Slope=#### ppm/s
When the Span value displayed on the screen is sufficiently stable,
press Enter. (Generally, when the Span reading changes by 1 % or less
of the full scale of the range being calibrated, for a period of ten minutes
it is sufficiently stable.) Once Enter is pressed, the Span reading
changes to the correct value. The instrument then automatically enters
the Analyze function.
4.4.3 Span Failure
The analyzer checks the output of the cell at the end of the span. If
the raw output of the cell is less than 0.5 μA/ppm O
2
, the span will not
be accepted. The analyzer will return to the previous calibration values,
trigger the System Alarm, and display the following message on the
VFD:
Span Failed!!
This message will be shown for five seconds and the instrument
shall return to the Analyze mode. In the upper right hand corner of the