Metrohm 746 VA Trace Analyzer - Manual (Page 190)

5.3.3 DOSIMATS
746 VA Trace Analyzer / 747 VA Stand
5-39
Softkeys Meaning
Start
dilution
Start dilution operation
With this softkey the dilution operation for preparing standard solu-
tions at the selected Dosimat/Dosino is started. For this operation, the
6.5611.010 pipetting equipment must have been installed at the
Dosimat/Dosino and connected to the remote interface of the 746 VA
Trace Analyzer (see section 3.10.6).
To prepare a solution with the volume V.end dilution and the
concentration C.end dilution out of a standard with the concentra-
tion C.init std proceed as follows:
• Select the Dosimat/Dosino with the mounted pipetting equipment
and press the softkey
for initializing the Dosi-
mat/Dosino and fill the transfer tubing.
• Press the softkey . The message Preparing
Dosimat #X appears.
• Put the pipetting tip into a waste container at about the same level
as the container with the standard solution and press the button on
the pipetting tip. After aspiration of the dilution solution the mes-
sage
Aspirating standard appears.
• Put the pipetting tip into the standard solution and press the button
on the pipetting tip. After aspiration of the standard solution the
message
Dispensing solution appears.
• Put the pipetting tip into the desired void container and press the
button on the pipetting tip. Standard and dilution solution are dis-
pensed into the void container. Afterwards the message
Next
operation / press to break appears.
• If you press , the Dosimat/Dosino will be ready for
another dilution, if you press , the Dosimat/Dosino is
switched to the exchange position.
Exchange
all
Switch all Dosimats/Dosinos to exchange position
In order to change the exchange or dosing unit, the 685 Dosimats or
700 Dosinos must be in the
exchange position. If the Dosi-
mats/Dosinos are in the dosing position, they have to be switched to
the exchange position by pressing or
.
After the exchange or dosing units have been changed, the Dosi-
mats/Dosinos must be initialized by pressing
or
.
Prime
all
Initialize all Dosimats/Dosinos
The burette cylinders of all Dosimats/Dosinos and all connecting
tubing up to the measuring vessel are automatically filled. Excess
solution is expelled to the measuring vessel.
Should the filling take longer than 30 s, the message
This operation
takes x.x minutes appears. The filling operation can then be started
with or aborted with to increase the filling rate. Once a filling
operation has been started, it can no longer be aborted.
After the filling, the initial volume
V.init is automatically delivered to
the measuring vessel. With V.init > 0 uL , the Dosimat/Dosino is
then in the dosing position and is ready for dispensing. With V.init
= 0 uL , the exchange position is retained, the Dosimat/Dosino is
ready for both dispensing and replacement of the exchange or dosing
unit.