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
Method-based leak test
Open the method:
• Go to EXTRACTION

OPEN METHOD and select
the requested method (e.g. PAH-01) and confirm
with OK. The name of the selected method now
appears in the main display.
Copy the parameters into the leak test:
• Open MENU

LEAK TEST. The LEAK TEST menu
consists of two columns. CURRENT METHOD
includes all settings of the currently active extrac-
tion method (for instance PAH-01). SELECT shows
the parameters of the last used leak test. To copy
all parameters of the current method to the leak
test press COPY. The cursor skips to the next entry.
Proceed similarly for all entries.
• Under ADDITIONAL PARAMETERS the flushing
conditions can be set, i.e. the receptacle to flush
into, the hold time and the flushing time are defined.
Start the leak test:
• Pressing START on the function buttons (not the
green START button) closes the extraction cells and
starts elevating the pressure by pumping solvent
into the cells. A first TIGHTNESS test checks the
presence of the extraction cells using nitrogen (see
section 6.4.2). The pressure remains constant at
7 bar (pre-pressure) before it elevates the pressure
to the set value (for example 100 bar) during the
PUMP step. In the hold step the position valves and
outlet valve are closed and the pressure is observed
over a constant time (approx. 5 min). The pressure
of each position as well as the overall pressure is
shown below the extraction cell. In addition, the
maximum pressure is designated by PRESSURE.
The leak test is stopped after the set hold time is
elapsed. Alternatively, the process can be stopped
by pressing SKIP (not the red STOP button). The
outlet valve opens, the solvent is discharged and
the system is flushed with nitrogen. The measured
pressure remains on the display. The evaluation of
leak tests is described later in this section.
Standard leak test
The reference settings are used for the standardized leak test.