SCP SCIENCE DigiPREP, Руководство по обслуживанию

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SCP SCIENCE
58
KeyPad
Version 1.0
Step 2 is the digestion step that completes the
destruction of organic nitrogen bonds. The solution at
the end of this step should be a clear coloured liquid.
If black spots remain in thesolution then the
digestion time needs to be extended. If the solution in
the tube turns to a solid at room temperature more
sulphuric acid needs to be added to the TKN diges-
tion reagent.
The Dual-Zone tube rack
should be lifted at the end of
the digestion step to allow
the tubes to cool as shown
in the picture (right).
It is not necessary to place
tubes in all positions during
a digestion.
CLEANING
If the surface is still hot, contact with
a liquid may create steam that can
scald you. It is important to allow the
instrument to cool before cleaning.
Cleaning of minor surface spills
Turn off the system and unplug the
Digi
PREP
HT
from the power source. Allow the system to cool.
Sponge up any excess liquid, dilute the area with
clean water, and wipe dry with a paper towel.
Cleaning of digestion wells
Turn off the system and unplug the Digi
PREP
HT
from the power source. Allow the system to cool
before proceeding further.
Suction the solution out of the well with an eye
dropper, squeeze bottle, or pipette. Dilute any
remaining spillage with water, two or three times, and
suction as much solution out as possible. Sponge
the remaining residue with a paper towel. Allow the
system to dry completely before powering up.
Cleaning of a major spill
If a solution has run down around and below
the graphite digestion block, turn off the system
and unplug
Digi
PREP HT
from the power source.
Allow the system to cool before proceeding
further.
Digi
PREP HT
must be disassembled,
cleaned,and thoroughly dried prior to running again.
Please consult the service
departmentfor help if required.
In order to access under the block, fi rst remove
the exhaust manifold and the insert rack from the
two-tier upright. Then remove the ‘U’ channel and
the white top ring. To do so, remove the two thumb
screws from the back of the system that holds the ‘U’
support with the two side panels connected. Lift the
‘U’ channel straight up and set off to the side.
To remove the block and inner heater pan, turn
the unit upside-down onto a soft surface, a piece
of cardboard is fi ne to do this on. Remove the four
locking nuts from the bottom of the support pan and
lift up on the outer housing. Lift gently as the over
temperature protection device and temperature
sensor are attached to the graphite block through
the side of the inner heater pan. The RTD probe and
over temperature bulb may be gently removed from
the graphite block. Caution should be exercised so
not to pinch the over temperature gas line. Access
is now available for cleaning the inner pan and other
affected areas.
The coated block surface may be cleaned with a
mixture of 100ml HNO
3
and 25ml HF in a litre of DI
water.
The Tefl on Exhaust manifold may be rinsed with
tap or DI water after each run. Place the manifold,
tube adapter side down to drain and dry. It is
fi
ne to run water through the manifold without
disassembling for cleaning purposes.
NOTE
WARNING