Teledyne 3000TA-XL-EU, Trace Oxygen Analyzer operating instructions Range Function

Trace Oxygen Analyzer Operation 4

•Defeated? Dft–Y/N(Yes/No)

•Failsafe? Fs–Y/N(Yes/No)

•Latching? Ltch–Y/N(Yes/No).

•To define the setpoint, use the < > arrow keys to move the blinking over to AL–1 ####. Then use the Δ∇ arrow keys to change the number. Holding down the key speeds up the incrementing or decrementing. (Remember, the setpoint units are ppm O2.)

•To set the other parameters use the < > arrow keys to move the blinking over to the desired parameter. Then use the Δ∇ arrow keys to change the parameter.

•Once the parameters for alarm 1 have been set, press Alarms again, and repeat this procedure for alarm 2 (AL–2).

•To reset a latched alarm, go to Dft– and then press either Δ two times or ∇ two times. (Toggle it to Y and then back to N.)

–OR –

Go to Ltch– and then press either Δ two times or ∇ two times. (Toggle it to N and back to Y.)

4.7The Range Function

The Range function allows the operator to program up to three concen- tration ranges to correlate with the DC analog outputs. If no ranges are defined by the user, the instrument defaults to:

Low = 0–1 ppm Med = 0–10 ppm High = 0–100 ppm.

The Model 3000TA-XL is set at the factory to default to autoranging. In this mode, the microprocessor automatically responds to concentration changes by switching ranges for optimum readout sensitivity. If the current range limits are exceeded, the instrument will automatically shift to the next higher range. If the concentration falls to below 85% of full scale of the next lower range, the instrument will switch to that range. A corresponding shift in the DC percent-of-range output, and in the range ID outputs, will be noticed.

The autoranging feature can be overridden so that analog output stays on a fixed range regardless of the oxygen concentration detected. If the

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