Metrohm 746 VA Trace Analyzer - Manual (Page 192)

5.3.3 DOSIMATS
746 VA Trace Analyzer / 747 VA Stand
5-41
Parameter Range; Default value / Meaning
Dosing rate 0.001...3.333*(V.burette) µµL...L/min; 2.00 mL/min
Dosing rate
Discharge rate of the Dosimat/Dosino. The maximum rate which can
be set depends on the burette volume of the mounted exchange or
dosing unit.
If the 4-way microtip 47 47 or another microcapillary tubing is used for the
addition of solutions from the Dosimat/Dosino to the measuring vessel,
the Dosing rate must be set to ≤ 2 mL/min .
Filling rate 0.001...3.333*(V.burette) µµL...L/min; 3.0*(V.burette) mL/min
Filling rate
Filling rate of the Dosimat/Dosino. The maximum rate which can be
set depends on the burette volume of the mounted exchange or
dosing unit.
At the end of a determination, the burette is automatically filled at this
filling rate.
V.init 0.00...2.00 mL; 0.00 mL
Initial volume
The initial volume V.init is the volume that is automatically dis-
pensed after filling of the burette cylinder. The purpose of this auto-
matic volume addition is to enlarge the accuracy of the first dispens-
ing operation following filling for the addition of small volumes.
For dispensing volumes ≤≤ 50 µµL, we advise working with an initial
volume of at least 50 µµL as without this automatic addition the first
dispensing operation following filling would be inexact.
V.tube in 0.0...(V.burette) mL; 0.7 mL
Volume of filling tube
The volume V.tube in is the volume of the tubing from the supply
bottle to the Dosimat/Dosino. To ensure an air-free filling of the tubing,
this volume must be determined and entered. For the standard
accessories of the Dosimat/Dosino, the following volumes should be
entered:
• 6.3014.XXX Exchange unit for 685 Dosimat: 1.7 mL
• 6.3030.XXX Dosing unit for 700 Dosino: 0.7 mL
V.tube out 0.0...999.9 mL; 0.2 mL
Volume of dosing tube
The volume V.tube out is the volume of the tubing from the Dosi-
mat/Dosino to the measuring vessel. To ensure an air-free filling of the
tubing, this volume must be determined and entered. With normally
used accessories for addition of standard or auxiliary solutions and
preparation of standard solutions using the pipetting equipment the
following volumes should be entered:
• Addition of standard solutions with
6.1624.000 4-way microtip:
0.2 mL
• Addition of auxiliary solutions
(see sections 3.9.3/4, 3.10.3/4)
3.0 mL
• 6.1562.050 pipetting tube: 4.8 mL