Foss Soxtec 2050 Manual Del Usuario página 56

11.6.2 Drive Unit
The positioning of condensers/cups and sample
rods in the Extraction Unit can be controlled man-
ually from the Drive Unit if necessary, See Fig.
5:7.
Fig. 5:7 pos 6: Controls the condensers and cups
with the up and down keys.
Fig. 5:7 pos 5: Controls the sample rods with the
up and down keys.
11.7 Operation
11.7.1 Control Unit Settings
Press the "POWER" key on the Control Unit
(switch should light up), and the display will
show the version number of the internal software
before going to standby, e.g. showing the previ-
ously run program.
Select a program #1 to #9 for Analysis by press-
ing 7 or 8. Check in the Application Sub Note
that the overtemperature setting is correct for the
solvent used, see temperature table, table 3, in
section 5.3.4 Overtemperature Setting p. 5:7.
Note: If the over-temperature set-
ting is not correct, or if there is no
recommendation in the table, check
with the laboratory supervisor that
the correct setting is used.
If the application is being run for the first time and
it is necessary to set up a new program, see next
section.
11.7.2 Setting Up a New Program
Use the relevant Application Sub Note and table
3 to set the correct temperatures and extraction
times for the method. First select a program, with
the 7 8 keys. Then use the 4 key and the 7
8 keys to set temperature and times for the dif-
ferent extraction steps. When finished, wait for
the display to stop blinking or press the 4 key un-
til you have passed the last extraction step. The re-
covery time should be set up according to experi-
ence of the time needed for recovery of the
solvent to the collection vessel. A typical value is
between 5 and 10 minutes depending on solvent
used and temperature. The fourth time can be
used to keep the hot plate warm for up to 59 min-
utes if more analyses are to be performed later.
11.7.3 Cooling Water
Cooling water must be supplied to the system be-
fore the analysis starts. Adjust the flow rate to 2 l/
min. The cooling water will be turned on/off au-
tomatically when the hot plate is turned on/off.
11.7.4 Preheating
The hot plate can be preheated prior to the analy-
sis by pressing the E key. The hot plate will
warm up to the set temperature for the program
shown in the display.
11.7.5 Preparation of the Sample
Sample preparation is very important for getting
correct results. For further information see Appli-
cation Note 301 and the relevant ASN for the type
of sample concerned (supplied by the FOSS Ana-
lytical AB representative). Some types of sam-
ples, e.g. meat, should be mixed with sand or
celite. Follow the same procedure as for tradition-
11:4
Soxtec™ 2050 Automatic System
al Soxhlet or recommended by the corresponding
standard method.
11.7.6 Extraction
1. Attach the thimbles to the adapters.
2. Weigh the sample into the thimbles, using the
thimble support with the balance.
3. Transfer the thimbles to the thimble stand, us-
ing the thimble handler. The thimble is re-
leased when the handle is pressed. The
thimble stand can be used for drying the sam-
ples.
4. Place a defatted cotton plug on top of the sam-
ple and place the thimbles in thimble supports
attached to the holder. Use the thimble sup-
port holder to insert the thimbles into the ex-
traction unit. Alternatively insert them by
hand, using surgical gloves or other protec-
tion to avoid contamination of the thimbles.
Insert the thimbles into the condensers as follows:
5. The default position of the system is position
1, in which the rods are ready for insertion of
the thimbles maually one by one and then
press the 9 key .
Alternative:
To insert thimbles using thimble holder, first
press the 9 key to raise the sample position-
ing rods into the condensers.
Check that the thimbles fit properly.
Warning
Careful handling of the solutions used
in an analysis is mandatory for labora-
tory safety. Refer to the appropriate
material safety data sheet for reagent
handling instructions. Wear eye pro-
tection at all times and handle hot
cups with care.
6. Insert the six extraction cups, tared with boil-
ing chips. Use the cup holder. Press the 9 key
to mate the cups with the condensers. Load
the cups with solvent using the connectors on
top of the Extraction Unit and the solvent ad-
dition kit connected to a dispenser.
7. Start the program on the Control Unit by
pressing the 6 key. The system automatical-
ly lowers and clamps the condensers and cups
to the hot plate, starts the countdown and per-
forms all movements for boiling, rinsing and
recovery according to the program tempera-
ture and time settings. You can change time
or temperature on the present step while run-
ning. Press the 4 key once for change of time
and press twice for change of temperature.
Step with the 7 8 keys.
Finally the system lifts the cups from the hot
plate to prevent the sample from being de-
stroyed by heat. The hot plate and cooling wa-
ter are turned off when the set time for the
drying step has been counted down.
User Manual 1000 7414 / Rev. 4