YSI pHotoFlex STD Colorimeter - Manual (Page 37)

pHotoFlex
®
STD Operation
37 ba76122e01 02/2013
4.5.4 Blank value (reagent blank value)
A blank value is required for every concentration measurement.
For some programs (methods) for concentration measurement, the
blank values are already stored in the meter. They are used automati-
cally. For all other programs, the blank value has to be determined sep-
arately before the first measurement.
Each stored reagent blank value can be replaced by a blank value de-
termined by the user.
You will find more information on blank values in the photometry anal-
ysis manual. A table with the programs and required blank values is in-
cluded in the analysis specifications.
A blank value is always stored for the program that has just been called
up. It remains stored until it is erased (menu item, Delete blank value)
or overwritten.
The Reset function erases all blank values measured by the user and
restores the blank values stored in the factory.
If a blank value measured by the user is stored for a program, this blank
value is used for measurement. The usage of the blank value mea-
sured by the user is documented and also indicated in the measured
value display.
Measuring the blank
value
The following measurement of the blank value applies only to the se-
lected program.
1 If necessary, press the <M> key several times until the mea-
sured parameter Concentration is selected.
2 Select a program with <PROG> as necessary.
3 Open the adjustment menu with <CAL/ZERO>.
4 Using <> <> and <START/ENTER>, select and start the
Measure blank value function.
The menu-guided blank value measurement begins.
Follow the instructions on the display.
Zero adjust.
Measure blank value
Delete blank value
Standard adjustment
Photometry \ Adjustment