Voith BTG Mutek PCD-06, Руководство по эксплуатации

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40 Operation Manual Mütek
TM
PCD-06 © BTG 2021
V. Measuring
5.8.2 General Method Settings
Method name
Name or rename a method here by pressing the text
field.
Short description
Here you can describe the method in a few words.
Your colleagues will honor this!
Settling time
A time to stabilize the mV signal at the beginning of a
test. After starting the measurement, the unit will count
down the settling time and then automatically start the
titration.
Hint
Use this function when the sample needs a certain time
to stabilize - and to make sure, that this time is always
the same in every test. No matter who is testing.
Type
EP stands for endpoint titration. Results are titrant
demand [ml] and charge density [µeq/l]. Default diagram
type is mV/ml.
IEP stands for iso-electric point titration. Result is the
IEP [pH] and the default diagram type is mV/pH.
Termination
Select if the titration endpoint should be at a mV or a pH
value.
Termination value
Adjust the value (mV or pH) you want the titration to
end.
Hint
The typical termination value of an EP titration is 0 mV.
However, there is no sharp cut at 0 mV, instead the sig-
nal will cross the zero line and show the opposite sign.
There is some over-titration taking place, but no worries
- the result will be calculated back to 0 mV.
Hint
The point of neutral charge is also the point of highest
instability of the sample. Flocks and coagulates form
and might break again under the strokes of the PCD
piston. This instability can cause the mV signal to
return, even if it has already crossed the 0mV mark. In
such a case you should consider setting a termination
value, that is beyond the point of zero charge (for
e50 mV for a negatively charged sample).
This makes sure, that all sample charge is neutralized
by the titration.
Pump
Select how titrant pumps are to be used:
Auto: the PCD will check the sign of the mV signal and
will automatically use the pump with the opposite sign.
1/+ or 2/-: independent from the mV signal, only the
selected pump will be used for titration.
Hint
Apply this function in case you use two cationic titrants,
for example one higher concentrated in position 1/+ and
one lower concentrated in position 2/-.