Metrohm 840 PC Control 5.0 / Touch Control - Manual (Page 285)

4 Parameters
PC Control / Touch Control
273
4.10.4 Monitored dosing (DOS)
A predefined volume of a solution is dosed with the DOS command.
The measured value and the temperature are monitored simultane-
ously.
• Dosing criterion: Two parameters from the following can be de-
fined: Volume, Dosing rate and Dosing time. The third parameter
is calculated according to the following formula:
rate Dosing time Dosing Volume ⋅ =
If continuous dosing is required, a tandem dosing setup (see Sec-
tion 4.1.5 ) can be used i.e. dosing is carried out with a combination
of two dosing devices. The second dosing device is dosing while
the first one is being filled and vice versa.
Depending on the type of task one of the following types of dosing
can be used:
Volume / Dosing rate
– You define the volume to be dosed and
the desired dosing rate. The filling times lengthen the dosing proc-
ess.
Single dosing
Dosing rate
Tandem dosing
Dosing rate
V/mL
t/s t/s
V/mL
Filling time
Fig. 4.18: Definition of volume and dosing rate
Volume / Dosing time – You define the volume and the time in
which this volume is to be dosed (particularly suitable for synthesis
applications). The dosing rate is automatically optimized by the Ti-
trando (see formula above).
Attention!
The time defined as Dosing time corresponds to the net dosing time
t
1
+t
2
, i.e. the filling time of the exchange or dosing unit is not taken
into account.