LaMotte SMART 2 - Manual (Page 14)

Below is a list of suggested wavelengths for the color of the reacted samples.
Use these as a starting point.
Sample
Color
Wavelength
Range
Yellow 430
Pink 520
Red 570
Green and Blue 620
n
CALIBRATION
As with all pre-calibrated meters, it is highly recommended, even if not
required by regulations, that the user periodically verify the performance of the
meter by running standards with a predetermined concentration. Results
outside of specification are an indication that the meter needs to be adjusted.
This can be done following the user calibration described on page 31. If the
user calibration fails to properly adjust the meter then the meter should be
returned to LaMotte Company for recalibration. (See page 5).
n
CALIBRATION CURVES
The Smart2 Colorimeter contains tests for the LaMotte reagent systems (see
Page 49). The first step in using a non-LaMotte reagent system with your
Smart2 Colorimeter is to create a calibration curve for the reagent system. To
create a calibration curve, prepare standard solutions of the test factor and use
the reagent system to test the standard solutions with the Smart2 Colorimeter.
Select a wavelength for the test as described above.
Plot the results (in ABS or %Transmittance) versus concentration to create a
calibration curve. The calibration curve may then be used to identify the
concentration of an unknown sample by testing the unknown, reading
Absorbance or %T, and finding the corresponding concentration from the
curve. The linear range of the reagent system can be determined and this
information can be used to input a User Test into the Smart2 Colorimeter (see
EDIT USER TESTS, page 36).
n PROCEDURE
1. Prepare 5 or 6 standard solutions of the factor being tested. The
concentration of these standards should be evenly distributed throughout
the range of the reagent system, and should include a 0 ppm standard
(distilled water). For instance, the solutions could measure 0, 10%, 30%,
50%, 70%, and 90% of the system’s maximum range.
2. Turn on the Smart2 Colorimeter. Select the appropriate wavelength from
the absorbance mode. Be sure to select the appropriate wavelength for the
color produced by the reagent system.
14 SMART2 COLORIMETER 1.07