Instruction Manual
760000-C
November 2002
Rosemount Analytical Inc. A Division of Emerson Process Management Operation 3-15
Model NGA2000 CLD
CLD
7.50 ppm
HOME
-- Linearization Functions --
INFO
Polynomial setup…
Midpoint correction setup…
Use the polynomial setup to generate a linearizing
polynomial from up to 20 gases. With more than 6 gases
it will produce a fourth order polynomial linearizer.
Use the midpoint correction for a piecewise-linear final
correction, to bring up to three points precisely onto
the curve.
ESCAPE
CLD
7.50 ppm
HOME
-- Polynomial Setup --
Range to be linearized: 1
Current span gas: 10.0 ppm
Calculated polynomial order: 4
Gas value shown is: ppm
Gas concentrations…
Analyzer function: READY
INFO
ESCAPE
CALC
CLD
7.50 ppm
HOME
Gas concentrations
Point 1
Gas value: 1.00
Raw reading: 0.9 ppm
Linearized value: 1.0 ppm
Point 2
Gas value: 2.00
Raw reading: 1.9 ppm
Linearized value: 2.0 ppm
Point to be measured: Point 1
Analyzer function: READY
INFO
ESCAPE
DATA
NEXT
e. Linearization
Functions
The linearization functions allow the pri-
mary variable output to be linearized by
either a polynomial of up to 20 set points,
or by midpoint piecewise correction with
up to three midpoints.
Main Menu
↓
Analyzer and I/O expert controls &
setup…
↓
Analyzer module setup…
↓
Gas measurement parameters…
↓
Linearization functions…
Figure 3-19. Linearization Functions
Menu
Polynomial Set Up
Use the polynomial set up to generate a
linearizing polynomial from up to 20
gases. With more than 6 gases, it will
produce a fourth order polynomial lin-
earizer.
Main Menu
↓
Analyzer and I/O expert controls &
setup…
↓
Analyzer module setup…
↓
Gas measurement parameters…
↓
Linearization functions…
↓
Polynomial set up…
Figure 3-20. Polynomial Setup Menu
Setup:
Select the range to linearize.
Make sure that the span gas value is cor-
rect and set into the “Correct span gas”
line.
Choose whether to define the gas con-
centrations as absolute values (ppm) or
as a percent of the span gas (Percent of
span gas) in the “Gas values shown as”
line.
Percent would be used if the span gas is
being diluted with a mixing device.
From the “Polynomial set up” menu
(Figure 3-20, page 3-15) select the “Gas
concentrations…” submenu to enter up to
20 points for each range.
Figure 3-21. Gas Concentrations Menu
In the “Gas concentrations” menu, enter
the gas value for the desired point as ppm
or percent of scan range in accordance
with the previous choice made for the
“Gas values shown as.”
