Teledyne 7300A manual Curve Algorithm Screen, Checking the linearization

Infrared Gas Analyzer Operation 4

Note: The ranges must be increasing from low to high, for example, if Range 1 is set to 0–10 % and Range 2 is set to 0–100 %, then Range 3 cannot be set to 0–50 % since that makes Range 3 lower than Range 2.

Ranges, alarms, and spans are always set in either percent or ppm units, as selected by the operator, even though all concentration-data outputs change from ppm to percent when the concentration is above 9999 ppm.

Note: When performing analysis on a fixed range, if the concentra- tion rises above the upper limit as established by the operator for that particular range, the output saturates at 1 V dc (or 20 mA). However, the digital readout and the RS-232 output continue to read regardless of the analog output range.

To end the session, send:

st<enter> st<enter>

to the analyzer from the computer.

4.8.2 The Curve Algorithm Screen

The Curve Algorithm is a linearization method. It provides from 1 to 9

intermediate points between the ZERO and SPAN values, which can be normal- ized during calibration, to ensure a straight-line input/output transfer function through the analyzer. (Before setting the alogorithm curve, each range must be Zeroed and Spanned).

Each range is linearized individually, as necessary, since each range will usuallyhaveatotallydifferentlinearizationrequirement.

To linearize the ranges, you must first perform the four steps indicated at the beginning of section 4.8 Programming. You will then be in the MAIN MENU and select ALOGORITHM.

4.8.2.1 Checking the linearization

From the MAIN MENU screen, select ALGORITHM, and Enter.

Sel rng	set	algo
—> Ø1	Ø2	Ø3	<—

Use the UP/DOWN key to select the range: 01, 02, or 03. Then press Enter.

Gas use: CO2

Range: Ø -10 %

Enter again.

Teledyne Analytical Instruments 4-29