Teledyne Trace Oxygen Analyzer Setting the Analog Output Ranges, Fixed Range Analysis

4 Operation Model 3000TA-XL-EU

concentration exceeds the upper limit of the range, the DC output will saturate at 1 V dc (20 mA at the current output).

However, the digital readout and the RS-232 output of the concentra- tion are unaffected by the fixed range. They continue to read accurately with full precision. See Front Panel description in Chapter 1.

The automatic air calibration range is always 0-25 % and is not pro- grammable.

4.7.1 Setting the Analog Output Ranges

To set the ranges, enter the range function mode by pressing the

Range button on the front panel.

L—1	M—10
H—100	Mode—AUTO

Use the < > arrow keys to blink the range to be set: low (L), medium (M), or high (H).

Use the Δ∇ arrow keys to enter the upper value of the range (all ranges begin at 0 ppm). Repeat for each range you want to set. Press Enter to accept the values and return to Analyze mode. (See note below.)

Note: The ranges must be increasing from low to high, for example, if range 1 is set as 0–100 ppm and range 2 is set as 0–1,000 ppm, range 3 cannot be set as 0– 500 ppm since it is lower than range 2.

Ranges, alarms, and spans are always set in ppm units (over the entire 0-250,000 ppm range), even though all concentration-data outputs change from ppm units to percent when the concentration is above 10,000 ppm.

4.7.2 Fixed Range Analysis

The autoranging mode of the instrument can be overridden, forcing the analyzer DC outputs to stay in a single predetermined range.

To switch from autoranging to fixed range analysis, enter the range function by pressing the Range button on the front panel.

Use the < > arrow keys to move the blinking over AUTO.

Use the Δ∇ arrow keys to switch from AUTO to FX/LO, FX/MED, or FX/HI to set the instrument on the desired fixed range (low, medium, or high).

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