Metrohm 765 Dosimat - Manual (Page 15)

2.2 Modes
765 Dosimat
11
• A new air bubble is built with every preparation step ("prep.") e.g. its volume increases.
If you wish to keep the volume of the air bubble expel it in mode DOS before changing
V-PIP.
• For best pipetting results we recommend exchange units with volumes ≤ 20 mL and
pipetting equipment 6.5611.000.
• The aspirating and expelling rates should not be higher than 20 mL/min.
• Hold tubing tip in an angle of app. 45° to the vessel wall during pipetting. Just the
same as you do with glass pipettes!
• The vessel, containing the liquid you want to pipette should stand on the same level as
the vessel into which you are going to expel the liquid in order to ascertain app. the
same level of the pipetting tubing during work.
2.2.5 Mode DIL, Diluting
Aspirating a stored pipetting volume and subsequent expelling of the pipetting and dilut-
ing volume.
V-PIP 0.1 ml
V-DIL 1. ml
Pipetting volume
Input range depends on the volume of the exchange unit:
1 mL
0.001... 0.900 mL
5 mL 0.001... 4.900 mL
10 mL 0.001... 9.800 mL
20 mL 0.002... 19.700 mL
50 mL 0.005... 49.500 mL
Diluting volume
Input range: 0.001...999.999 mL
Note: The diluting liquid is unintentionally mixed with the
pipetted liquid if it is aspirated into the burette cylinder!
The aspiration tube must contain V-PIP!
Expelling and filling rate see page 6.
If mode DIL is loaded, the display shows
DIL * 0.000 ml
.
The sign * in the display tells you that mode DIL is not ready to be used. With a
preparation step is carried out during which V-PIP is expelled into the bottle of the
exchange unit and an air bubble is built to separate the solution of the exchange unit from
the sample.
Then the Dosimat is ready to aspirate the pipetting volume (0.1 mL) which is displayed by
DIL 1 0.100 ml
and carried out after pressing .
Then
DIL 2 1.100 ml
is displayed which means that the Dosimat is ready to expel the
pipetting and the diluting volume (0.1 mL + 1 mL = 1.1 mL). This is executed after
. The preparation step is now carried out automatically and the Dosimat is ready to
aspirate the next pipetting volume.
VOLUME
RATE