Teledyne 3020T operating instructions Cell Failure, Span Cal, Auto Mode Spanning

4 Operation Model 3020T

4.8.1.3Cell Failure

Cell failure in the 3020T is usually associated with inability to zero the instrument down to a satisfactorily low ppm reading. When this occurs, the 3020T system alarm trips, and the VFD displays a failure message.

#.#ppm Anlz

CELL FAIL/ ZERO HIGH

Before replacing the cell:

a.Check for leaks downstream from the cell, where oxygen may be leaking into the system.

b.Check your span gas to make sure it is within specifications.

c.If there are no leaks and the span gas is OK, replace the cell as described in chapter 5, Maintenance.

d.After correcting the condition, reset the Cell Fail Alarm by taking the analyzer into, and then back out of, STANDBY.

4.8.2 Span Cal

SPAN is used to span calibrate the analyzer. Span calibration can be performed using the automatic mode, where an internal algorithm compares consecutive readings from the sensor to determine when the output matches the span gas concentration. Span calibration can also be performed in manual mode, where the operator determines when the span concentration reading is acceptable and manually exits the function.

4.8.2.1Auto Mode Spanning

Scroll to SPAN, and ENTER the SPAN function. The screen that appears allows you to select whether the span calibration is to be performed automatically or manually. Use the DOWN/UP control to toggle between AUTO and MAN span settling. Stop when AUTO appears on the display.

Span: Settling: AUTO

<ENT> For Next

Use ENTER to move to the next screen.

Span Val: 209000.00 <ENT>Span <UP>Mod #

Use DOWN/UP to start changing the oxygen-concentration. Use ESCAPE/ENTER to blink the digit you are going to modify. Use DOWN/UP again to change the value of the selected digit. When you have finished

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