Operating
TOPwave
34
The TOPwave can hold up to 24 digestion vessels. Vessel types must not be mixed as
this will result in extreme differences in sample heating.
The procedure employed for all vessel types is basically similar. This section therefore
first describes the general procedures, while any differences between the vessel types
will be dealt with in detail in the following sections.
Weigh the sample material into the vessels and then add the acid. The maximum
sample quantity depends on the vessels employed and must be strictly observed
(see section "Technical Data" p. 71).
CAUTION
In each pressure vessel, at least approx. 7 ml of liquid should be employed so that the
temperature sensor can determine the sample temperature precisely.
The microwave oven requires a certain minimum load of approx. 20 ml of liquid. If lower
volumes of liquid must be used, at least 3 vessels must be used for each run in order to
achieve the required total load.
If the fluid amount employed is too small, the oven may be damaged during longer ope-
ration! An inadequate liquid load can also result in rotor overheating and, in the worst
case, in rotor damage.
Visually inspect the rupture discs.
In case of extensive traces of corrosion or other visible damage to the rupture discs, they
must be replaced for safety reasons. A bulge in the center of the rupture disc after use is
normal and will not affect its functions. Make sure the rupture disc is properly seated in
the lid, that is, that its edge sits uniformly in the lid groove.
Press the seal lip on the appropriate molded part to spread the seal ring on the clo-
sure and then place the lid on the lower part of the vessel.
Make sure that the seal ring is equably spread.
Seal the vessel with the coupling cup. For this purpose it is sufficient to close it hand-
tight without exerting additional force.
The rotor should be loaded with the digestion vessels as symmetrically as possible
and the digestion vessels connected to the receptacle.
Insert first vessel in the position marked “1” and arrange the rest symmetrically (see
section "Positioning of the vessels in the rotor" p. 77).
Seal any unused positions on the collection vessel with the supplied blind stoppers or
with lock screws in order to ensure the proper operation of the gas removal.
Sample amount
Closing vessels
Inserting the vessels