Rack adjustment – Metrohm 840 PC Control 5.0 / Touch Control User Manual
Page 78

3.10 Device manager
66
PC Control / Touch Control
• Rack position: Each special beaker can be assigned to any rack
position. However, they should preferably be assigned to high rack
positions so that sample series can be started with rack position 1.
Rack positions that have been defined as special beaker positions
are no longer available as sample positions.
• Work pos. Tower 1/2: A specific work position can be defined for
each special beaker. See also Section 3.24.6.
• Beaker radius: Enter here the actual radius of the beakers at the
special beaker positions of the rack. This beaker radius must not be
smaller than the "Min. beaker radius" defined in the device
properties of the tower (see p. 60). Before the lift is moved to the
work position, these two values will be compared and, if necessary,
an error message will be displayed.
• Beaker sensor: Each time that this special beaker is moved to with
the MOVE command then, the beaker sensor will check if a beaker
is present. If the sample beaker is missing the method sequence
will be halted and a corresponding message will be shown. For the
option "Robotic arm" a Swing Head must be installed and a
suitable work position with beaker contact must be defined for the
lift, as this position will be moved to for beaker recognition.
If you exit the edit dialog for the rack table with [Back] or [Home] then
you must confirm the message that appears with [Yes] in order for the
altered rack data to be transferred to the USB Sample Processor. [No]
rejects the alterations.
Rack adjustment
If necessary, each sample rack can be finely adjusted, i.e. the rack
offset is determined in the direction of rotation. The adjustment of a
rack is usually not necessary. However, if the exact positioning of a
robotic arm is necessary for a high degree of accuracy (e. g. for very
small sample beakers) then a fine adjustment can be carried out. Place
the affected rack in position and carry out a rack reset (under manual
control). The adjustment is carried out at rack position 1.
Procedure:
Open the dialog System/Device manager.
Select the USB Sample Processor and press [Edit].