OHAUS AquaSearcher AP50MM Manual De Instrucciones página 19

EN-19
5.6. Multiple Timing Steps Method
Some colorimetric methods have two or three timing steps. The AP50MM shows a
count-down timer for the timing steps before the last timing step (Figure 12). During
these timing steps, one or more reagents are added to the sample, or operations such
as swirling the vial to mix the reagent and the sample are being performed. These
methods usually use one vial for the prepared blank and the other for the prepared
sample.
In order to show the concentration-time curve as shown in Figure 12 during the last
timing step, The AP50MM must be zeroed using the prepared blank before the last
timing step. Thus, the last timer button will not be selectable until the AP50MM has
been zeroed using the prepared blank. Multi-timing step Hach® methods require
zeroing the colorimeter using the prepared blank after the last timing step is
completed. The SP- 800 can optionally be re-zeroed using the prepared blank after
the last timing step. The blank value measured will be subtracted from the
concentration value measured at the end of the last timing step. Optionally, the READ
button could be pressed to read the prepare sample again.
The following procedure is typical for methods having two-timing steps:
1.
Press the TMR1 button to start the first timer. Complete the necessary
operations to prepare the blank and the sample.
2.
Place the prepared blank into the AP50MM sample vial compartment and
press the ZERO
button.
3.
Place the prepared sample into the AP50MM sample vial compartment and
press the TMR2 button to start the second timer. The AP50MM will display the
measured concentration as a function of time as shown in Figure 12.
4.
When the timing step is completed, the measured concentration will be
displayed on the top right of the screen. The timing step could be terminated
earlier by pressing STOP button.
2022/07/19 08:00
Figure 12. Multiple Timer Method
a-AP50MM