Voith BTG Mutek PCD-06, Руководство по эксплуатации

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42 Operation Manual Mütek
TM
PCD-06 © BTG 2021
V. Measuring
5.8.4 Time
Here you can program the time interval between two
titrant dosing steps.
Fixed :
A dosage will take place every time as programmed
here.
Hint
You want to make sure, that the mV signal has stabili-
zed after a titrant dosage. If you notice that the mV sig-
nal is still busy stabilizing while the next titrant injection
already takes place, select a higher value here.
Dynamic :
Selecting this mode, the time interval between two
dosing steps will be set under dynamic control. Parame-
ters for controlling the time interval are ΔE (Stability), Δt
(Stability), tmin and tmax. The approach is to achieve a
certain signal stability - defined via ΔE (Stability) and Δt
(Stability) - until the next dosage can take place. The
minimum and maximum waiting times for this stability
are tmin and tmax.
The increment is within the range between minimum
(dVmin) and maximum(dVmax) increment.
Example :
ΔE (Stability) is 1 mV, Δt (Stability) is 1 s, tmin is 5 s and
tmax is 15 s. Means that the PCD continuously checks
for the defined stability criterion: the signal must not
swing more than 1 mV within 1 s.
And it waits at least 3 s, but not longer than 15 s for this
stability criterion to be achieved.
Hint
Dynamic time control is the preferred mode for IEP titra-
tions. Acid or base additions can make the mV signal
swing strongly. A further acid or base injection should
only take place when the signal swinging is over.
Start dynamic control at:
You can adjust, at which mV value all dynamics pro-
grammed under "Volume" and "Time" should start.
Hint
Titrations oftentimes have a distinct constant part and
become variable when approaching the point of neutral
charge. You might want to bridge the constant part fast
and the dynamics to kick in only when the signal beco-
mes variable. So, observe the titration curve and read
out the mV value where the slope starts to change. Set
this value as starting point for the dynamic control.
If no dynamics (DYN) are selected under "Volume" or
"Time", this feature is hidden.