Consort C832 Anleitung Seite 16

Sample addition:
The analate addition method is used when the samples vary widely in temperature
or have a 5 to 100 times higher concentration than the available standard. The
most suitable increment can be found from: increment percentage < 100 x
standard value / expected sample value.
1. Press MODE until the display shows [Dir.CONC1], [Std.Add1], [Std.Sub1],
[Anl.Add1] or [Anl.Sub1] and choose [Anl.Add1]. Press MODE to proceed.
2. The display shows one of the possible increments (1, 2, 5, 10, or 20 %), e.g.
[10% Incr]. Select the desired value and press CAL.
3. Prepare a standard solution of the measured species. Its value should be 5 to
100 times lower than the expected sample concentration. The display shows
one of the possible standards e.g. [Std 3.-6]. Select the desired value and
press CAL.
4. After rinsing the electrodes with distilled water, immerse them in e.g.
100 ml standard solution. The display will show the electrode potential e.g.
[E= 281.5]. When readings are stable press CAL.
5. Add a small increment corresponding to the chosen mode (e.g. 20 ml). The
display will show the difference in electrode potential e.g. [dE=23.9]. When
readings are stable press CAL. The instrument calculates the result and shows
the concentration of the sample in the same unit as the standard used for the
addition.
6. For a next measurement press CAL and the same procedure starts again from
point 4). Press MODE to abort.
Sample subtraction:
The analate subtraction method is used to measure species for which stable
standards or ion selective electrodes do not exist. The procedure is similar to
the analate addition method. The most suitable increment can be found from:
increment percentage < 100 x standard value / expected sample value.
1. Calculate the stoichiometric ratio (n) of the reaction: xS + yR > SxRy n=x/y (S
= sample, R = reagent).
2. Press MODE until the display shows [Dir.CONC1], [Std.Add1], [Std.Sub1],
[Anl.Add1] or [Anl.Sub1] and choose [Anl.Sub1]. Press MODE to proceed.
3. The display shows one of the possible increments (1, 2, 5, 10, or 20 %), e.g.
[10% Incr]. Select the desired value and press CAL.
4. Prepare a standard solution of the measured species. Its value should be 5 to
100 times lower than the expected sample concentration. The display shows
one of the possible standards e.g. [Std 1.-6]. Select the desired value and
press CAL.
5. After rinsing the electrodes with distilled water, immerse them in e.g.
100 ml standard solution. The display will show the electrode potential e.g.
[E= 129.3]. When readings are stable press CAL.
6. Add a small increment corresponding to the chosen mode (e.g. 1 ml). The
display will show the difference in electrode potential e.g. [dE= 41.7]. When
readings are stable press CAL. The instrument calculates the result and shows
the concentration of the sample in the same unit as the standard used for the
addition.
7. Calculate the real concentration by multiplying the result with the
stoichiometric ratio (n). For a next measurement press CAL and the same
procedure starts again from point 5). Press MODE to abort.
C831 • C832 • C833 • C835 • C838
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