Hach Portable Spectrophotometer DR 2800 - Manual (Page 54)

54
Standard Operations
5.5.5 Sample blank
Turbidity and color in the sample matrix can falsify the results of a
photometric analysis. The interference factors come from the
sample or are created by reactions with the reagents.
The influence of turbidity and/or color can be eliminated or reduced
by taking a sample blank reading.
In the barcode mode, a special cuvette/vial (TNT919) containing
the sample blank is placed in cell compartment #1 after the sample
reading has been taken and is automatically measured. The
sample reading is then corrected by adding or subtracting the blank
value. The final result is displayed, with the message "After blank
value corr.".
Some barcode tests do not require a sample blank value to be
determined, as turbidity and color are dealt with during the test
procedure. Other barcode tests use the reagent test vials to
determine the sample blank. Please refer to the Hach procedure for
method-specific instructions.
Save as User Program To store the selected parameters as a User Program, see section 6.1 on page 61 .
Recall Data Call up saved measurement data or time courses, see section 5.3 on page 37 .
Instrument Setup Basic data of the instrument, see section 5.2 on page 27 .
Table 5 Barcode program options (continued)
Options Description