Endress+Hauser Analytik Jena APU 28 Series User manual

Operating Manual
APU 28 Series
AOX Sample Preparation Systems
with control unit connect

Manufacturer Analytik Jena GmbH
Konrad-Zuse-Straße 1
07745 Jena / Germany
Phone: [phone]
Phone: [phone]
Mail: [email protected]
Technical Service Analytik Jena GmbH
Konrad-Zuse-Straße 1
07745 Jena / Germany
Phone: [phone]
Fax: [phone]
Email: [email protected]
General Information http://www.analytik-jena.com
Documentation Number 11-0607-004-23
Edition A (01/2023)
Technical Documentation Analytik Jena GmbH
© Copyright 2023, Analytik Jena GmbH
For a proper and safe use of this product follow the instructions. Keep the
operating manual for future reference.

APU 28 Series Table of contents
3
Table of contents
1 Basic information ................................................................................................................................................. 5
1.1 About this manual ............................................................................................................................................ 5
1.2 Intended use ..................................................................................................................................................... 6
2 Security ................................................................................................................................................................. 7
2.1 Safety labeling on the device ........................................................................................................................... 7
2.2 Requirements for the operating personnel..................................................................................................... 8
2.3 Safety instructions for transport and commissioning..................................................................................... 8
2.4 Safety instructions: during operation .............................................................................................................. 9
2.4.1 Summary of safety instructions ....................................................................................................................... 9
2.4.2 Safety instructions: protection against explosion and fire ............................................................................. 9
2.4.3 Safety instructions – electrical equipment ...................................................................................................... 9
2.4.4 Handling of auxiliary and operating materials ............................................................................................... 10
2.5 Safety instructions–maintenance and repair ................................................................................................ 10
2.6 Behavior during emergencies .......................................................................................................................... 11
3 Function and design ............................................................................................................................................. 12
3.1 Functionality ..................................................................................................................................................... 12
3.2 Design................................................................................................................................................................ 15
3.3 Connections and interfaces.............................................................................................................................. 19
3.4 Tube system...................................................................................................................................................... 21
4 Installation and commissioning ........................................................................................................................... 23
4.1 Ambient conditions and space requirements ................................................................................................. 23
4.2 Power supply..................................................................................................................................................... 23
4.3 Unpacking and setting up the device............................................................................................................... 24
5 Operation.............................................................................................................................................................. 28
5.1 Operating the control module control unit connect ....................................................................................... 28
5.1.1 Creating a rack setup and managing setups ................................................................................................... 31
5.1.2 Calibrating racks and managing rack configurations...................................................................................... 35
5.1.3 Changing software settings.............................................................................................................................. 38
5.1.4 Retrieving system information......................................................................................................................... 39
5.2 Performing a sample enrichment.................................................................................................................... 40
5.2.1 AOX sample preparation .................................................................................................................................. 40
5.2.2 SPE-AOX sample preparation process............................................................................................................. 42
5.2.3 Display during sample enrichment.................................................................................................................. 44
5.2.4 Stopping sample processing and editing a section during operation............................................................ 45
6 Maintenance and care.......................................................................................................................................... 47
6.1 Maintenance overview ..................................................................................................................................... 47
6.2 Replacing tubes................................................................................................................................................. 47
6.3 Venting and rinsing the tube system............................................................................................................... 48
6.4 Change aspiration needle................................................................................................................................. 50
6.5 Changing the seals on the dosing head .......................................................................................................... 51
6.6 Check dosage .................................................................................................................................................... 51

Table of contents APU 28 Series
4
7 Transport and storage.......................................................................................................................................... 52
7.1 Transport........................................................................................................................................................... 52
7.2 Preparing the device for transport................................................................................................................... 52
7.3 Moving the device in the laboratory................................................................................................................ 53
7.4 Storage .............................................................................................................................................................. 54
8 Disposal ................................................................................................................................................................ 55
9 Specifications........................................................................................................................................................ 56
9.1 Technical data................................................................................................................................................... 56
9.2 Standards and directives .................................................................................................................................. 57

APU 28 Series Basic information
5
1 Basic information
1.1 About this manual
These operating instructions describe the sample preparation systems of the APU 28
with the APU 28/1 S and the APU 28/1 SPE as well as their operation with the control
unit connect. The devices and the control module are configured together and provided
in a set as APU28connect S and APU28connect SPE. Both configurations will be re-
ferred to collectively in the following as APU28 connect. Differences will be explained in
the corresponding sections.
The control unit connect control module is also offered separately for retrofitting devices
of the APU 28. In this case, these instructions for operation and maintenance of the
converted devices are also valid.
The device is intended to be operated by qualified specialist personnel who must ob-
serve all instructions given in the operating manual.
The operating manual provides information about the design and operation of the de-
vice and provides operating personnel with the necessary know-how for safe handling of
the device and its components. Furthermore, the operating manual includes information
on the maintenance and servicing of the device as well as information on potential
causes of malfunctions and their correction.
Conventions Instructions for actions occurring in chronological order are numbered and combined
into action units.
Warnings are indicated by a warning triangle and a signal word. The type, source and
consequences of the hazard are stated together with notes on preventing the hazard.
Elements of the control and analysis program are indicated as follows:
¡Program terms are in bold (e.g., the System menu).
¡Menu items are separated by vertical lines (e.g., System|Device).
Symbols and signal words used
in this manual
The user manual uses the following symbols and signal words to indicate hazards or in-
structions. These warnings are always placed before an action.
WARNING
Indicates a potentially hazardous situation which can cause death or very serious (possi-
bly permanent) injury.
CAUTION
Indicates a potentially hazardous situation which can cause slight or minor injuries.
NOTICE
Provides information on potential material or environmental damage.

Basic information APU 28 Series
6
1.2 Intended use
The sample preparation systems of the APU 28 are used for the automated enrichment
of adsorbable organically bound halogens (AOX) in aqueous solutions on activated car-
bon. The sample preparation systems work according to the column method according
to DIN EN ISO 9562, EPA1650C, EPA9020B and others. It is possible to set individual
parameters that deviate from the norm.
The devices are supplied with the removable control unit connect for APU 28 with touch
display.
The double channel system APU28connect S enriches two AOX samples on activated
carbon in parallel.
The single channel system APU28connect SPE enriches AOX and SPE-AOX samples on
activated carbon. In the case of SPE-AOX samples, automated solid phase extraction
(SPE) precedes the AOX adsorption.
Both systems can also be used to enrich samples for AOF determination.
The devices are equipped with racks for working with Analytik Jena columns
(18x6mm). Optionally, the devices can be configured with racks for the use of alterna-
tive AOX columns with the dimensions 40x9mm and 47x6mm. If required, you can
expand the systems with additional racks.
The device and its components may only be used for the analyses listed in the user man-
ual. Only this specified use is regarded as the intended use, ensuring the safety of the
user and the device.

APU 28 Series Security
7
2 Security
For your own safety and to ensure error-free and safe operation of the device, please
read this chapter carefully before commissioning.
Observe all safety instructions listed in this user manual and all messages and infor-
mation displayed on the monitor by the control and analysis software.
2.1 Safety labeling on the device
Warning and mandatory action labels have been attached to the device and must al-
ways be observed.
Damaged or missing warning and mandatory action labels can cause incorrect ac-
tions leading to personal injury or material damage. The labels must not be removed.
Damaged warning and mandatory action labels must be replaced immediately!
The following warning and mandatory action labels have been attached to the de-
vice:
Warning symbol Meaning Comment
Warning of crushing At the sampler arm
There is a risk of crushing hands in the
movement area of the sampler arm.
Warning of cuts At the sampler arm
There is a risk of injury at the aspira-
tion needle during operation.
Warning of hand in-
juries in gear drive
At the sampler arm
There is a risk of hand injuries at the
Z-drive.
The following GHS pictographs are affixed to the storage bottles for safety labeling
of the chemicals:
GHS pictograph Meaning Comment
Corrosiveness warning On the storage bottle for acidic sodium
nitrate rinsing solution (pH≈1.7)
The acidic rinsing solution causes skin
burns and severe eye damage.
Warning against
flammable substances
On the storage bottle for methanol
(only for SPE-AOX)
Methanol is flammable and can cause
burn injuries if ignited.
Methanol can lead to poisoning and
organ damage.
Warning of acute toxic-
ity
Health hazard

Security APU 28 Series
8
Mandatory signs/
information sym-
bols
Meaning Comment
Disconnect the power
supply before opening
the device cover
At power supply: Before opening the
device cover, switch off the device and
disconnect the mains plug from the
mains socket.
Observe the operating
manual
On the mains switch: Before starting
work, read the operating manual.
For People's Republic of
China only
The device contains controlled sub-
stances. Analytik Jena GmbH warrants
that these substances will not be re-
leased from the device within the next
25years provided the device is em-
ployed as intended.
2.2 Requirements for the operating personnel
The device must only be operated by qualified specialist personnel instructed in the
use of the device. This instruction also include teaching the contents of this user
manual and of the user manuals of the connected system components. We recom-
mend training by qualified employees of Analytik Jena or its representatives.
In addition to the safety instructions in this user manual, the general applicable
safety and accident prevention regulations of the respective country the device is op-
erated in must be observed and adhered to. The operator must ensure the latest ver-
sion of these regulations.
The user manual must be accessible to the operating and service personnel.
2.3 Safety instructions for transport and commissioning
Incorrect installation can create serious hazards. This may cause an electric shock.
¡Only the Analytik Jena customer service or specialist personnel trained and au-
thorized by them is allowed to install and commission the device and its system
components.
¡Unauthorized assembly and installation is not permitted.
¡Insufficiently secured components pose a risk of injury. During transport, secure
the device components as specified in this operating manual.
¡Only transport the device in its original packaging. Ensure that all transport pro-
tections have been fitted and the device is completely empty.
¡Loose parts must be removed from the system components and packed sepa-
rately.
To prevent health damage, the following must be observed when moving the device
in the laboratory (lifting and carrying):
¡For safety reasons, two persons are required to transport the device who must
hold the device by either side of the equipment.
¡The device has no carrying handles. To transport the device, grip the device
firmly at the bottom with both hands and lift it at the same time.

APU 28 Series Security
9
¡Risk of damage to health due to improper decontamination! Perform a profes-
sional and documented decontamination of the device before returning it to An-
alytik Jena. The decontamination report is available from Service when register-
ing the return. Without a completed decontamination report, the acceptance of
the device will be refused. The sender may be liable for damage caused by inade-
quate decontamination of the device.
2.4 Safety instructions: during operation
2.4.1 Summary of safety instructions
The operator must make sure that the device and its safety equipment is in sound
condition each time before starting up the device. This applies in particular after
each modification or extension of the device or its repair.
Observe the following:
¡The device may only be operated if all items of protective equipment (e.g. covers
in front of electronic components) are in place, properly installed and fully oper-
ational.
¡The sound condition of the protection and safety equipment must be checked
regularly. Any defects must be corrected as soon as they occur.
¡Protective and safety equipment must never be removed, modified or switched
off during operation.
¡Risk of crushing in the movement range of the sampler arm, especially to hands.
Hands and fingers can be crushed in the drives. There is a risk of puncture and
cut injuries at the needle. Maintain a safety distance from the sampler arm dur-
ing operation.
¡Caution when handling glass components. Risk of broken glass and therefore risk
of injury!
¡Modifications, conversions and extensions to the device are only permitted after
consultation with Analytik Jena. Unauthorized modifications can jeopardize the
device’s operational safety and may lead to limitations regarding the warranty
and access to customer service.
2.4.2 Safety instructions: protection against explosion and fire
The device may not be operated in an explosive environment.
2.4.3 Safety instructions – electrical equipment
Lethal voltages may occur in the device! Contact with live components may cause
death, serious injury or painful electrical shock.
¡Work on the electronics may only be carried out by the customer service of Ana-
lytik Jena and specially authorized technicians.
¡The power plug must be connected to a proper power outlet to ensure that the
device meets protection class I (ground connector). The device may only be con-
nected to power sources whose nominal voltage is the same as that on the rating
plate of the equipment. Do not replace the removable power cable of the device
with a power cable that does not meet the specifications (with no protective
ground conductor). Extensions of the supply cable are not permitted!
¡The basic module and the system components may only be connected to the
mains when they are switched off.

Security APU 28 Series
10
¡Electrical connection cables between the basic module and the system compo-
nents may only be connected or disconnected when the device is switched off.
¡Ensure that no liquid enters the interior of the device, for example at cable con-
nections. There is a danger of electric shock.
¡Before opening the device’s housing, the device must be switched off using the
mains switch and the mains plug must be disconnected from the power outlet.
¡The device automatically moves the sampler arm for initialization each time it is
switched on. The device also performs initialization when power is restored after
a power failure. There is a risk of accident in the operating range of the arm.
2.4.4 Handling of auxiliary and operating materials
The operator is responsible for the selection of substances used in the process as well
as for their safe handling. This is particularly important for radioactive, infectious,
poisonous, corrosive, combustible, explosive and otherwise dangerous substances.
When handling hazardous substances, the locally applicable safety instructions and
instructions in the safety data sheets from the manufacturers of the auxiliary and op-
erating materials must be complied with.
¡For the operation of the sample preparation system, nitric acid nitrate solution
(pH≈1.7) is used as rinsing solution. For the SPE-AOX process, methanol is also
required as an eluent. Observe the regulations and instructions in the safety data
sheets for the handling of the corrosive rinsing solution and methanol. Always
wear goggles and protective gloves when handling these hazardous materials.
Observe the notes on the labels.
¡Ensure good room ventilation in working rooms.
Observe the following:
¡The operator is responsible for carrying out suitable decontamination should the
device become contaminated externally or internally with dangerous substances.
¡Splashes, drops or larger liquid spillages should be removed using an absorbent
material such as absorbent cotton, laboratory wipes or cellulose.
¡In case of biological contamination, wipe the affected area with a suitable disin-
fectant. Then wipe the cleaned areas so that they are dry.
¡The only suitable cleaning method for the housing is wipe disinfection. If the dis-
infectant has a spray nozzle, apply disinfectant to a suitable cloth before using it
on the device.
Proceed with particular care and ensure utmost cleanliness when working with
infectious material because the device cannot be decontaminated as a whole.
¡Before using a cleaning or decontamination procedure other than the one pre-
scribed by the manufacturer, the user is required to check with the manufacturer
that the intended procedure will not damage the device. Safety labels attached
to the device must not be moistened or wiped with methanol.
2.5 Safety instructions–maintenance and repair
The device is generally maintained by the customer service department of Analytik
Jena or specialist personnel trained and authorized by them.
Unauthorized maintenance can damage the device. For this reason, only the activi-
ties described in the user manual in the "Maintenance and care" chapter may be per-
formed by the operator.
¡Only clean the exterior of the device with a slightly moistened, non-dripping
cloth. Use only water and, if required, customary surfactants.

APU 28 Series Security
11
¡All maintenance and repair work on the device must only be carried out when
the device is switched off (unless specified otherwise).
¡Use only original spare parts, wear parts and consumables. They have been
tested and ensure safe operation. Glass part are wear parts and are not subject
to the warranty.
¡All protective equipment must be reinstalled and checked for proper function
when the maintenance or repair work is complete.
2.6 Behavior during emergencies
If there is no immediate risk of injury, switch off the device and the connected system
components immediately in hazardous situations or in the event of an accident and/
or disconnect the power plugs from the power outlets.
Always ensure free access to the main switch as well as to the mains connection on
the rear of the device.

Function and design APU 28 Series
12
3 Function and design
3.1 Functionality
The sample preparation systems of the APU 28 enrich adsorbable organically bound
halogens (AOX) on activated carbon. The devices operate according to the column
method (in accordance with DIN EN ISO 9562, EPA1650C, EPA9020B) and prepare up
to 28 aqueous samples fully automatically for AOX determination. The processing time
for a sample is about 45min. The environmental parameter AOX includes organic chlo-
rine, bromine and iodine compounds. All device models can also be used to enrich sam-
ples for AOF determination.
In addition, the APU 28/1 SPE model allows the fully automatic SPE-AOX enrichment.
With the preceding solid phase extraction, the average processing time for one sample is
110to120min.
AOX enrichment process As the placement diagram shows, one sample is arranged on the sample tray in each
case and one duplex column to its left.
Fig.1 Placement diagram for AOX samples
Sample
Duplex column
Fig.2 Arrangement of sample vessels and duplex columns
In a first step, the sample preparation system stirs the current sample to mix it homoge-
neously. Then the device picks up the sample with the aspiration needle and pumps the
sample slowly over the duplex column at the same time.

APU 28 Series Function and design
13
1
23
4
Fig.3 AOX adsorption diagram
1 Dosing head 2 Duplex column
3 Aspiration needle 4 Sample in sample vessel
The device then rinses the loaded activated carbon in the duplex column with an acidic
nitrate rinsing solution (pH≈1.7) in order to remove inorganic chlorine compounds
(matrix). The residual sample and the rinsing solution run via the drainage channel on
the sample tray into the waste canister.
At the end of each sample preparation, the device backwashes the tube system and nee-
dle with rinsing solution and is then ready for the next sample.
According to the DINENISO9562 standard, the device operates with the following set-
tings:
¡Sample volume 100ml
¡Rinsing volume 25ml
¡Dosing rate 3ml/min
You can adjust the settings individually.
Equip each duplex column with two quartz containers. The quartz containers are sup-
plied as ready-filled disposable columns, but can also be refilled. The quartz containers
contain 50mg activated carbon between two plugs made of a temperature-stable fiber
material.
The activated carbon binds organically bound halogen compounds on its large surface.
When adsorption is complete, the activated carbon in the first tube binds the bulk of
AOX. Only a small amount is expected on the second tube. Always analyze both quartz
containers after sample preparation.
If water samples have a high percentage of organic compounds, the bulk of AOX may
not adsorb on the first tube. A similarly high or even higher AOX content is then mea-
sured on the second tube. This phenomenon is called breakthrough. In this case, it is
recommended to dilute the samples before sample preparation.
SPE-AOX enrichment process The SPE-AOX method is used for the enrichment of organically bound halogens in aque-
ous solutions with a high content of inorganic chlorides (>1g/l) according to ISO 9562,
if prior dilution of the sample cannot be performed. Highly saline waters can be, for ex-
ample, industrial wastewater. Wastewater in municipal wastewater treatment plants
can also be heavily contaminated with chlorides, for example due to road salt in winter.
The SPE-AOX method separates organic compounds from the highly saline matrix in a
first step by solid phase extraction. After elution with methanol, AOX enrichment takes
place on activated carbon.

Function and design APU 28 Series
14
Insoluble inorganic and organic halogen compounds and halogens adsorbed on solids
are not detected by this method. Samples containing particles must be filtered before
adsorption.
As the placement diagram shows, one SPE-AOX sample preparation occupies two sam-
ple locations on the tray at a time. You can place a maximum of 12 SPE-AOX samples on
the tray. Wiper and waste container for the spent SPE columns are to be placed on posi-
tion 28.
You can load a rack with SPE and AOX samples.
If you are only preparing SPE samples, the last row of trays must remain free. The dos-
ing head does not reach this last row. However, you can fill up the free spaces with AOX
samples.
Fig.4 Placement diagram for SPE-AOX samples
Sample
Duplex column
SPE column
Presented water
Fig.5 Arrangement of sample vessels and columns
For the SPE-AOX method, place the sample, the supply of ultrapure water, and the two
columns on the tray as follows:
Rack placement
Sample In sample vessel on an even position number n
SPE column Left of the sample
Supply of ultrapure water In sample vessel on an uneven position number (n – 1)
Duplex column Left of the supply of ultrapure water
Automated SPE-AOX enrichment proceeds as follows:

APU 28 Series Function and design
15
1 2 3 4
Fig.6 Diagram of the SPE-AOX method
1 SPE column conditioning 2 Sample application on SPE column
3 AOX desorption from SPE column 4 AOX application on duplex column
Step 1 serves the preparation. The device conditions the SPE column with methanol. In
the further course, the SPE column does not run dry.
In step 2 the device meters the sample on the SPE column. AOX is adsorbed on the SPE
column. The rest of the sample drains into the waste canister via the drainage channel.
The device rinses the SPE column with rinsing solution before and after sampling.
In step 3 the dosing head lifts the SPE column. The dosing head moves over the sample
vessel with ultrapure water and desorbs the bound AOX with methanol from the col-
umn. In the sample vessel, the eluate is diluted with the ultrapure water in the vessel
and mixed homogeneously by stirring. The device rinses the SPE column with nitrate
rinsing solution.
In control software default mode, the device uses 5ml methanol and 5ml nitrate rins-
ing solution to desorb the sample from an SPE column. In expert mode, the volumes can
be freely chosen. The total volume in the sample vessel is calculated as follows:
Vwater + Vmethanol + Vrinsing solution = Vtot
Then the device scrapes off the SPE column into the waste container on position 28.
In step 4 the aspiration needle picks up the diluted eluate. At the same time, the device
pumps the solution over the duplex column on which the actual AOX enrichment on ac-
tivated carbon takes place. The device rinses the duplex column with nitrate rinsing so-
lution.
3.2 Design
The sample preparation system consists of the following components:
¡Basic device APU 28 including power supply
¡Storage bottle holder
¡Removable control module control unit connect with touch display on a magnetic
holder
The control module controls all operations from the movement of the sampler arm, to
the pump unit, to the magnetic stirrer.
Basic device The sampler arm of the basic device moves the aspiration needle and the dosing head to
the respective sample position on the rack. The aspiration needle picks up a sample from
the sample vessel. The dosing head simultaneously meters the sample onto the column.
The stirrer bracket on the back of the device allows the device to mix the current sample.
The nitrate rinsing solution and a storage bottle with methanol (SPE-AOX only) are at-
tached to the basic device in a removable holder. The pump unit also meters these solu-
tions according to the preset operating sequences.

Function and design APU 28 Series
16
The rack has a drainage channel through which residues of the sample and the rinsing
solution drain into the waste canister. Before starting a sample preparation process, it is
necessary to adjust movements of the sampler arm to the rack or to check the adjust-
ment. The control software stores the offset values (calibrations) of up to .6 racks. Check
the calibration every time you change the rack. Always secure duplex columns to the
rack with a .30° twist. Otherwise, the dosing head could lift the duplex columns.
The four device feet are height-adjustable.
1
2
3
4
5
6
10
11
9
8
7
Fig.7 Single-channel system APU28connect SPE comprising basic device APU
28/1 SPE and control module
1 Autosampler arm 2 Pump unit
3 Dosing head 4 Control module control unit connect
5 Rack with duplex columns and sample
vessels
6 Basic device with height-adjustable feet
7 LED for status display 8 Aspiration needle
9 Position 28 (for wiper and waste con-
tainer SPE columns)
10 Canister for nitrate rinsing solution
11 Storage bottle with methanol (SPE-AOX
only)
Devices of the APU 28 series are equipped with a sample rack, further accessories and a
consumables starter set:
¡Magnetic stirring rod
¡Duplex columns for quartz container
¡Canister for nitrate rinsing solution
¡Sample vessels (maximum volume 120ml)
¡Waste canister
¡Pack of disposable columns with activated carbon
Double-channel system APU
28/1 S
The double channel system can enrich two AOX samples in parallel. The model has two
dosing heads and two aspiration needles. It processes two adjacent samples with the
same settings. The processing time for a maximum of 28 samples of approx.
10h30min is half the time required by the single channel system.

APU 28 Series Function and design
17
Fig.8 Double channel system APU 28/1 S with 2 dosing heads and needles
Single channel system APU
28/1 SPE
With the single channel system you can enrich SPE-AOX samples as well as AOX sam-
ples. The more complex SPE-AOX process is suitable for solutions with high salinity. The
process performs a solid phase extraction before the actual AOX adsorption on activated
carbon. Solid phase extraction first accumulates AOX on an organic resin, separating the
saline matrix.
You can place AOX and SPE-AOX samples together on one rack. This will give you a lot
of flexibility. Note, however, that you always need two sample locations on the rack for
one SPE-AOX sample. Here, the specimen must be placed on a straight specimen posi-
tion. The last row of the rack must be left empty for SPE-AOX-only samples. Positions
25 and 26 are only available for AOX-only sample preparation.
Wiper and waste container for spent SPE columns are placed on position 28. After AOX
desorption, the dosing head moves to this position and wipes off the spent SPE column.
The column falls into the waste container.
1
2
Fig.9 Discarding SPE columns
1 Wiper for SPE columns 2 Waste container
In addition, the single channel system is equipped with the following components:
¡Methanol storage bottle
¡Pack SPE columns
¡Fixture for SPE columns
¡Wiper and waste container for SPE columns (for position 28)
Configurations of the APU 28
series
The APU28connect S device configuration contains the APU 28/1 S and the control
module.

Function and design APU 28 Series
18
The APU28connect SPE device configuration contains the APU 28/1 SPE and the con-
trol module.
Optional configuration with
column flexibility rack
By default the devices of the APU 28 series are equipped with racks for the preparation
of Analytik Jena columns (18 x 6 mm). However, they can be optionally configured with
the column flexibility rack for alternative columns (40x9mm, 47x6mm).
1
2
Fig.10 Column flexibility rack for alternative columns
1 Flexible rack for third-party tubes 2 Duplex columns for third-party tubes

APU 28 Series Function and design
19
3.3 Connections and interfaces
7
2
6
1
3
4
5
Fig.11 Rear of the device
1 Autosampler arm with pump unit 2 Type plate
3 Electrical connections, interfaces 4 Magnetic holder with control module
5 Main switch, device fuses, mains con-
nection
6 Stirrer arm
7 Holder with storage bottle for nitrate
rinsing solution
The main switch, the power connection for the detachable power cord and the inter-
faces are located on the rear of the device.
The nozzle for the waste hose is located on the rear at the bottom right of the basic de-
vice. Make sure that the waste hose is connected and runs with a steady slope down to
the waste canister.
The magnetic holder for the control unit connect module is mounted on the right side
with two hexagon socket screws. The interface cable is long enough for you to detach
the control module and place it on the table or hold it in your hand during setup.
Interfaces The interfaces connect the basic device with the control module, the stirrer, the sampler
arm as well as the solenoid valves and the pump unit.

Function and design APU 28 Series
20
2
345
6
7
8
10
9
11
1
Fig.12 Connections and interfaces
1 Power supply for solenoid valves and
pump unit
2 Connection socket (not used)
3 "Stirrer" interface (to magnetic stirrer) 4 "Aux" interface for controlling the xyz
drives of the sampler arm
5 RS 232 interface (not used) 6 Power supply for solenoid valves and
pump unit
7 "Aux" interface for controlling the xyz
drives
8 Control module interface
9 Magnetic holder for control module 10 Main switch, device fuse, mains connec-
tion
11 Waste hose connection
Type plate The type plate contains the following information:
¡Manufacturer identification
¡Model name
¡Model number
¡Serial number
¡Year of manufacture
¡Conformity marks