Hach DR 2800, User Manual, Page: 52 / 96

52
Advanced Operations
Calibration by Entering Calibration Values
1. Select the Enter Values and press
NEXT
.
2. To enter the standard concentrations and corresponding
absorbance values in the displayed table, press the "
+ " symbol.
Use the alphanumeric keypad to enter the values.
Note: For faster data entry, enter all the concentration values, then all
the absorbance values, or vice versa.
Press
OK
and enter the corresponding absorbance value.
Press
OK
.
The entered data are displayed in the table. Repeat the
sequence for each data point you need to enter.
3. To change a value in the table, activate the appropriate line,
press the unit key (e.g. mg/l) or Abs and enter the changed
value via the alphanumeric keypad.
4. When the data have all been entered, press
GRAPH
to display
the curve that results from plotting the entered data.
Note: The correlation coefficient (r
2
) is shown on the left below
the axes.
5. The linear equation corresponds to the standard setting. Press
NEXT CURVE
to display the polynomial 2nd order curve. Press
NEXT CURVE
again, to display the polynomial 3rd order curve.
6. Press
FORCE 0
to change the setting from Off to On. The curve
now passes through the origin of the coordinate system.
7. Press
TABLE
to display the table again.
8. When the table has been completed and the curve type has
been chosen, press
DONE
when the graph is displayed or
EXIT
when the table is displayed. Go to section 6.1.1.4 on page 54 .