Buchi SpeedExtractor E-914, Operation Manual

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6 Operation
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SpeedExtractor E-916 / E-916XL / E-914 Operation Manual
Activate all positions together:
• Open EXTRACTION

OCCUPIED POSITIONS.
Confirm “Occupy all positions?” with YES. The main
display shows all activated positions as numbered
cylinders.
Deactivate positions:
• To activate only the four middle positions, activate
all positions first and then deactivate the positions 1
and 6. Go to EXTRACTION

OCCUPIED POSI-
TIONS and this time negate with NO. All positions
are deactivated now. Press ALL ON and move
the cursor to the vacant positions (in the current
example 1 and 6) and deactivate it by pressing OFF
or using the selection knob. The main display now
shows the vacant positions as crossed out cylinders.
NOTE
Never run the instrument with empty positions. In order to achieve uniform conditions, always place
identical empty extraction cells in the vacant positions. Therefore, using different sized extraction
cells in the same run is not recommended.
6.2.5 Leak test
The LEAK TEST feature allows the operator to check quickly and safely whether the instrument is
ready for operation. It is also a reliable measure to check the quality of the cup seals. A regular check
before operation is therefore recommended, and is mandatory after a longer period of non-use and/
or after replacement of the cup seals. There are two distinct approaches to perform a leak test. Firstly,
very commonly the tightness of the system is checked using the very same parameters as for the
subsequent extraction procedure. This allows the operator to evaluate the tightness on the basis of his
own operating parameters.
Secondly, in a more absolute approach the leak test is always performed using the same reference
settings. Thus, it is possible to reach conclusions on the basis of constant parameters. This is recom-
mended in order to observe the long term behavior of the instrument, particularly of the seals or to
ensure correspondence on a method-independent basis, relative to the same set of parameters. In
contrast to a regular extraction method, to perform a leak test it is recommended to preheat the in-
strument with the extraction cells placed in the heating block for 15 min to avoid thermal fluctuations.
Common to both approaches is the sample and instrument preparation:
• Preheat the instrument with the extraction cells placed in the heating block. It is not necessary to
equip the cell with the plug screw (see section 6.2.3 and 6.4.1).
• Activate all positions (see section 6.2.4).
• Place empty collection vials into the collection rack and put it on the instrument as described in
section 6.4.1.