6 limits conc, Limits conc – Metrohm 781 pH/Ion Meter User Manual
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6 Methods / Parameters
780/781 pH/Ion Meter, Manual
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configuration see Section 2.3.3, pH/Ion Meter configuration see Sec-
min.conc
1.0E-30...0.1...1.0E+30
max.conc.
1.0E-30...1.0...1.0E+30
The standard concentrations to be calculated lie within the range of
these minimum and maximum concentrations. Depending on the re-
quired number of standards (see above), the pH/Ion Meter will calculate
the other concentrations. The expected resulting potential difference
between all the standards remains constant.
V init
0.001...100.0...999.9 mL
The initial volume of a presentation (e.g. buffer, TISAB, etc.) is entered
here.
no.of Exchange Units. 1...5
It is normally a good idea to calibrate ion-selective electrodes over sev-
eral concentration decades. It is possible that a single Dosimat ex-
change unit may not be sufficient for this. In this case you can prepare
several exchange units with the corresponding different concentrations
of standard solutions:
conc.1...n
1.0E-30...100.0...1.0E+30
V Exchange Unit 1...n: 1, 5, 10, 20, 50 mL
For each exchange unit you must enter the concentration of the solution
it contains and the volume of the dosing cylinder. Arrange the exchange
units with increasing concentration of the standard solutions.
Please make sure that all exchange units have been prepared before
the start of a calibration sequence (dosing cylinders freshly filled, air
bubbles removed, etc.). The request for changing the exchange unit is
given on the display. This message describes the required standard
concentration and volume increment at the Dosimat Plus.
fill dosimat, dV/dt max.
dV = 1 ul, c = 2000.0 ppm
After mounting and filling the prepared exchange unit, continue with
<ENTER>.
6.5.6
Limits Conc
(applies only to measurement type: direct)
PARAMETER Conc
:
├
limits Conc
: └
state
In the direct measuring modes the pH/Ion Meter has a limits function
which allows the control of the parameter to be monitored. The control
signals are transmitted via the MSB connection to the optional remote