BEHR behrotest K8 User manual

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behrotest®K8 / K12 / K20/
K16 / K24 / K40
Digestion Unit
User‘s Manual

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Please read this operating manual carefully before starting use of your new K8 / K12 / K20 / K16 / K24 / K40
digestion unit!
The manual introduces you to the use of the apparatus with clear and simple guidance.
For reasons of safety in use of the system, please follow all safety warnings carefully. These are designated in the
text by a warning symbol .
Additional information, which is useful and important for an understanding of the manner of operation of the
apparatus, is denoted by a stripe in the margin.
We wish you success in the use of the

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Safety Advice
Danger of burns! The digestion tubes and the inner zone of the heating block get hot!
Never touch the hot glasses or the area of the heating block around the digestion tubes with the
bare hands.
Danger of electric shock!
Always install all cables in such a way that they cannot come into contact with the hot inner zone
of the heating block; they could otherwise smoulder through! Always ensure that no liquids can
come into contact with cable connections or the interior of the heating block! Always withdraw
the mains plug before opening the unit! Repairs on electrical, electronic and mechanical modules
of this appliance may be performed only by authorized specialist staff.
Danger of injury in case of breakage of glass! Always adhere to your professional association's
regulations when handling glass parts!
Care is required when using and handling acids and alkalis! Danger of corrosive burns and
injuries! ! Adhere to the current Hazardous Substances Ordinance!
Hazard from toxic gases!
During the Kjeldahl digestion, vapours of sulfuric acid (and other toxic gases) are set free. They
could harm your health and damage the apparatus and your lab equipment.
Always perform digesting operations which can result in evolution of toxic or corrosive vapours
using a scrubber system! Place the digester and the scrubber in a fume cupboard.
Never operate the digestion unit in wet, humid or explosion‑endangered areas!
Maximum air humidity = 80%
Maximum temperature = 40° C

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Contents
Safety Advice ............................................................................................................................................................. 3
Scope of supply......................................................................................................................................................... 5
Correct use of the device.......................................................................................................................................... 5
Overview of the behr K8 / K12 / K20 / K16 / K24 / K40 ........................................................................................... 6
Setting up................................................................................................................................................................... 8
Handling ..................................................................................................................................................................... 9
Switching the appliance on .................................................................................................................................... 11
Using the K8 / K12 / K20 / K16 / K24 / K40............................................................................................................. 11
The operating unit .........................................................................................................................................................11
The Start menu............................................................................................................................................................. 12
Configuring the K8 / K12 / K20 / K16 / K24 / K40 to meet your needs ........................................................................ 12
Creating a temperature program.................................................................................................................................. 14
Processing samples ..................................................................................................................................................... 16
Maintenance of your K8 / K12 / K20 / K16 / K24 / K40 ............................................................................................... 18
Cleaning the Exhaust Collector.................................................................................................................................... 18
Keep your Device Working Reliably as Long as Possible................................................................................... 19
Do Not Use Damaged Vessels!.................................................................................................................................... 19
Always Use a Scrubber!............................................................................................................................................... 19
Don‘t Leave Any Places Empty!................................................................................................................................... 19
Avoid bumping!............................................................................................................................................................. 20
Foaming ....................................................................................................................................................................... 20
What do I do if...?..................................................................................................................................................... 21
Technical Data ......................................................................................................................................................... 22
Customer Service.................................................................................................................................................... 22

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behrotest®K8 / K12 / K20 / K16 / K24 / K40
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© behr Labor-Technik GmbH
Scope of supply
Please check the contents of the pack for completeness
and freedom from damage immediately upon receipt.
Claims resulting from damage during transportation
which is externally apparent must be lodged immediately
with the carrier (i.e., the post/mail service, the railway
administration, the freight organization, etc.) - see the
label on the packaging.
In case of damage which is not apparent from outside
(„concealed transportation damage“), please contact the
behr after-sales service immediately upon discovery of
the damage. The same applies in the case of any other
complaints.
Address:
behr Labor-Technik GmbH
Spangerstrasse 8
D-40599 Düsseldorf, Germany
Telephone: [phone]
Telefax: ([phone]
e-mail: [e-mail]
Your K8 / K12 / K20 / K16 / K24 / K40 digestion unit is
packed in three parts:
Heating block, ready assembled with mounting rail for
sample rack and exhaust collector
Sample rack
Exhaust collector, ready assembled, with glass grid
and mounting frame
Plus
1 set of sample vessels matching to the digestion unit
Exhauster hose for connection to a behrosog process
exhauster system, for example
Drip pan, to be installed under the exhaust collector.
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Correct use of the device
The behrotest® K8 / K12 / K20 / K16 / K24 / K40 diges-
tion unit is used for heating of samples in the appropriate
digestion tubes. It is used, in particular, for quantitation of
total nitrogen using the Kjeldahl digestion method.
The digestion unit can be heated to 430 ° C. Always
ensure that you have selected the temperature program
appropriate to your samples. Use the digestion tubes
appropriate to this temperature, e.g. behrotest®diges-
tion tubes. Only use the appropriate type of digestion
tubes (round-bottom tubes).
Please under all circumstances note and adhere to the
following items, in order to ensure the greatest possible
operating safety and reliability and the longest possible
service-life for your digestion unit:
Always operate the appliance in accordance with
the instructions and data contained in this operating
manual!
Modifications to the appliance will result in forfeit of
any guarantee claims and can result in serious defici-
encies in the unit‘s operating safety and reliability.
During te Kjeldahl digestion, solfuric acid vapours
(and other aggressive gases) are set free. Always
operate the appliance with a scrubber system (e. g.
behrosog) and place the appliance and the scrubber
in a fume cupboard.
Never under any circumstances expose the dige-
stion unit to aggressive vapours, such as fumes from
acids, alkalis or solvents!
Always operate the behrotest® K8 / K12 / K20 / K16 /
K24 / K40 digestion unit under normal laboratory condi-
tions.
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behrotest®K8 / K12 / K20 / K16 / K24 / K40
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1
2
3
1.31.4
1.5
1.6
1.7
1.8
3.5
3.3
3.4
2.2
2.3
2.4
2.1
1.1 - 1.2 →
3.1
3.2
2.5 - 2.9 →
1 Heating block :
1.1 Operating unit
1.2 Mains switch
1.3 Heating slots for sample vessels
1.4 Aeration slots
1.5 Mains plug
1.6 Mounting rail, with:
1.7 Hooks for suspending the sample rack while not
in use
1.8 Cut-outs for suspending the exhaust collector
while not in use
2 Sample rack
2.1 Handles
2.2 Upper guide roller; it also serves for suspending
the sample rack on the hooks 1.7
2.3 Lower guide roller
2.4 Sample vessels
Overview of the K8 / K12 / K20 / K16 / K24 / K40

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behrotest®K8 / K12 / K20 / K16 / K24 / K40
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© behr Labor-Technik GmbH
1
2
3
1.11.2
2.5
←1.3 - 1.8
2.7
2.6
2.8
2.9
4
2.5 Front lid, removable
2.6 Fold for fastening the front lid on the frame of
the sample rack
2.7 Middle part of the frame, to hold the fold (2.6) of
the front lid
2.8 Hooks for fastening the front lid on the lower
frame bar of the sample rack
2.9 Lower bar of the frame, to hold the hooks (2.8)
of the front lid
3 Exhaust collector:
3.1 Handles
3.2 Gas outlet
3.3 Socket for suction hose
3.4 Suction hose
3.5 Hooks for suspending the exhaust collector in
the cut-outs 1.8 on the mounting rail
4 Drip pan

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behrotest®K8 / K12 / K20 / K16 / K24 / K40
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Setting up
Position the heating block on the place provided in
the fume cupboard. It should be located to the left of
and adjacent to the exhauster system. Leave some
room to the left and right; the aeration slots must be
free.
Insert the sample vessels into the sample rack.
Position the sample rack on the heating block.
Connect the exhauster hose to the socket on the rear
panel of the exhaust collector.
For the moment suspend the exhaust collector in the
cut-outs on the top end of the mounting rail. Check
that it is securely engaged.
Connect the exhauster hose to your process
exhauster system.
Drip pan
After finishing a digestion, insert the drip pan below the
exhaust collector. Insert the drip pan on the rail under
the bottom of the exhaust collector and shift it in. Lift it
up a bit so the hook can engage on the front panel of
the exhaust collector. Don’t forget removing the drip pan
before starting the next digestion.
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behrotest®K8 / K12 / K20 / K16 / K24 / K40
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© behr Labor-Technik GmbH
Handling
The behrotest®K8 / K12 / K20 / K16 / K24 / K40 makes
it quick and easy for you to insert your samples into the
heating block and to remove them for cooling down.
Thus you are always sure that all samples have been
treated exactly the same.
Why not get acquainted with the handling right now?
Parking the sample rack
On the middle of the mounting rail in the rear of the heat-
ing block you will see two hooks to hang the sample rack
on. When lifting the sample rack out of the heating block,
run it along the mounting rail, and it will engage in the
hooks automatically.
Grasp the sample rack using the two red handles.
Lift the rack carefully. Run it along the mounting rail
while doing so. Lift the rack upward until you hear it
engage.
Lower the rack carefully onto the hooks, in order to
check that it has engaged correctly. If this is not the
case, lower it again and repeat the above procedure.
Now the device is in the same position as before the
start of a digestion.
Insertig the samples into the heating block
Grasp the sample rack using the two red handles.
Position the sample rack on the digestion unit in such
a way that the sample vessels locate in the holes in
the digestion unit.
Take the exhaust collector from the top of the
mounting rail, and place it on top of the sample rack.
The upper parts of the PTFE stoppers will rest on the
rims of the sample vessels, and the suction tubes will
go into the sample vessels so the fume extractor can
remove any vapours coming out of them.
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behrotest®K8 / K12 / K20 / K16 / K24 / K40
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Removing the samples from the heating block
When the digestion is completed, you should take the
samples out of the heating block but leave the exhaust
collector on the sample rack until the samples have
cooled down. So now you need to lift the sample rack
along with the exhaust collector out of the heating block
and park them.
Grasp the sample rack using the two red handles.
Lift the rack carefully, together with the exhaust col-
lector. Run it along the mounting rail while doing so.
Lift the rack upward until you hear it engage.
Lower the rack carefully onto the hooks, in order to
check that it has engaged correctly. If this is not the
case, lower it again and repeat the above procedure.
Parking the exhaust collector
Grasp the exhaust collector using the two red
handles.
Remove the exhaust collector from the sample rack
and suspend it in the cut-outs at the top end of the
mounting rail.
Front lid on the sample rack
Danger of burn! The front lid gets hot! o
not try to remove the front lid while a dige‑
stion is in progress.
The lid on the front side of the sample rack may be taken
off. Thus you have the samples in view while digestion is
in progress.
For routine digestions you should leave the front lid on.
With the front lid on, less heat will escape so you will
save energy.
Removing and remounting the front lid
Put the sample rack on an even surface.
For taking the lid off, hold the sample rack down and
pull the lid upwards until it can be taken off.
For putting the lid on, insert it in a way as for the
hooks and the fold to engage behind the lower and
middle part of the sample rack frame, as indicated.
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