Trace Oxygen Analyzer

Operation 4

 

 

 

 

 

 

 

 

 

The beginning zero level is shown in the upper left corner of the dis- play. As the zero reading settles, the screen displays and updates information on Slope (unless the Slope starts within the acceptable zero range and does not need to settle further).

Then, and whenever Slope is less than 0.08 for at least 3 minutes, instead of Slope you will see a countdown: 1 Left, 0 Left, and so fourth.

These are two steps in the zeroing process that the system must complete, AFTER settling, before it can go back to ANALYZE.

####

PPM

Zero

1 Left=###

 

ppm/s

The zeroing process will automatically conclude when the output is within the acceptable range for a good zero. Then the analyzer automatically returns to the ANALYZE screen.

4.8.1.2Manual Mode Zeroing

ENTER the ZERO function. The screen that appears allows you to select between automatic or manual zero calibration. Use DOWN/UP to toggle between AUTO and MAN zero settling. Stop when MAN appears on the display.

Zero: Settling: Man

<ENT> To Begin

ENTER to begin the zero calibration. After a few seconds the first of five zeroing screens appears. The number in the upper left hand corner is the first-stage zero offset. The microprocessor samples the output at a predeter-

mined rate. It calculates the differences between successive samplings and displays the rate of change as Slope= a value in parts per million per second

(ppm/s).

#### ppm Zero

Slope=#### ppm/s

NOTE:It takes several seconds for the true Slope value to display. Wait about 10 seconds. Then, wait until Slope is sufficiently close to zero before using ENTER to finish zeroing.

Generally, you have a good zero when Slope is less than 0.05 ppm/s for about 30 seconds. When Slope is close enough to zero, ENTER it. In a

few seconds, the screen will update.

Once zero settling completes, the information is stored in the microprocessor, and the instrument automatically returns to the ANALYZE screen.

Teledyne Analytical Instruments

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Teledyne 3020T operating instructions Trace Oxygen Analyzer Operation, Manual Mode Zeroing