Hach DR 2800, User Manual, Page: 51 / 96

51
Advanced Operations
Press a factor key and use the alphanumeric keypad to enter a
factor. If the formula includes more than one factor, press another
factor key and enter another factor, and repeat until all the factors
have been entered. Press
OK
. When all the relevant data have
been entered, press
NEXT
.
Note: Up to five digits can be entered, including a maximum of 4 decimal
places to the right of the decimal.
Concentration Resolution (Single and Multi-wavelength)
Select the required number of decimal places from the displayed
list and press
NEXT
.
Chemical Form (Single and Multi-wavelength)
Chemical representation of the analysis parameter in the
result display.
Use the alphanumeric keypad to enter the chemical form and press
NEXT
to enter Calibration settings (see section 6.1.1.3 on page 51 ).
6.1.1.3 Calibration Settings for Single and Multi Wavelength Mode
A method is calibrated by determining the absorbance values of
several standard solutions of known concentration.
There are three ways to create and store a calibration curve.
Instructions for each method follows
Table 8 .
Table 8 Calibration Settings
Mode Descriptions
Enter Values
A calibration table is created by entering the concentration values and the absorbance values of the
analyte solution. The absorbance values are plotted versus standard concentrations and the calibration
curve is displayed as a graph (page
52 ).
Read Standards
A calibration table is created by entering the concentration values of the standard solutions and then
measuring the absorbance of the analyte solutions. The absorbance values are plotted versus standard
concentrations and the calibration curve is displayed as a graph (page
53 ).
Enter Formula
If the calibration curve can be determined from the mathematical relationship between concentration and
absorbance by linear regression, etc., the corresponding formula can be selected (linear, 2nd or 3rd
order polynomial) from a list and the appropriate factors can be entered (page
54 ).