KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: info@kern-sohn.com
Phone: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Operating manual
Electronic Moisture Analyser
KERN DAB
Version 1.3
2018-08
GB
DAB-BA-e-1813
2 DAB-BA-e-1813
GB
KERN DAB
Version 1.3 2018-08
Operating manual
Electronic Moisture Analyser
Contents
1 TECHNICAL DATA ............................................................................................. 4
2 DECLARATION OF CONFORMITY ................................................................... 5
3 APPLIANCE OVERVIEW ................................................................................... 6
3.1 Keyboard overview ....................................................................................................................... 8
3.2 Overview of display ...................................................................................................................... 9
4 BASIC INFORMATION (GENERAL) ................................................................ 10
4.1 Proper use ................................................................................................................................... 10
4.2 Improper Use ............................................................................................................................... 10
4.3 Warranty ...................................................................................................................................... 10
4.4 Monitoring of Test Resources ................................................................................................... 10
5 BASIC SAFETY PRECAUTIONS ..................................................................... 11
5.1 Pay attention to the instructions in the Operation Manual .................................................... 11
5.2 Symbols used in the operating instructions ............................................................................ 11
5.2.1 Warning pictograms ............................................................................................................. 12
5.3 Personnel training ...................................................................................................................... 12
5.4 Danger Information ..................................................................................................................... 13
6 TR ANSPORT AND STORAGE ......................................................................... 15
6.1 Testing upon acceptance ........................................................................................................... 15
6.2 Packaging / return transport ...................................................................................................... 15
7 UNPACKING, SETUP AND COMMISSIONING ............................................... 15
7.1 Installation Site, Location of Use .............................................................................................. 15
7.2 Unpacking and checking ........................................................................................................... 16
7.2.1 Scope of delivery / serial accessories: ................................................................................. 16
7.3 Placing ......................................................................................................................................... 17
7.4 Levelling ...................................................................................................................................... 18
7.5 Mains connection........................................................................................................................ 19
7.6 Switching on and off................................................................................................................... 19
7.6.1 Initial Commissioning ........................................................................................................... 20
7.7 Connection of peripheral devices ............................................................................................. 20
8 ADJUSTMENT .................................................................................................. 21
8.1 Weight adjustment ...................................................................................................................... 21
8.2 Calibrate / adjust temperature of the heating module ............................................................ 23
8.2.1 Temperature calibration ....................................................................................................... 23
8.2.2 Temperature adjustment ...................................................................................................... 26
DAB-BA-e-1813 3
9 CARRY OUT YOUR FIRST MEASUREMENT ................................................. 27
10 DEFINE DRYING PARAMETERS ................................................................. 29
1. Enter ident number for drying method ..................................................................................... 29
2. Set heating profile....................................................................................................................... 30
3. Selecting switch-off criterion .................................................................................................... 32
4. Set drying temperature .............................................................................................................. 33
5. Setting the drying period for time-controlled switching-off ................................................... 34
11 CARRYING OUT DRYING AND MEASURING PROCESSES ..................... 35
12 RS 232 INTERFACE ..................................................................................... 38
12.1 Technical data ......................................................................................................................... 38
12.2 S etting the baud rate .............................................................................................................. 38
12.3 P rint out protocol: .................................................................................................................. 39
12.4 Continuous data transmission .............................................................................................. 40
13 GENERAL INFORMATION CONCERNING MOISTURE ANALYSIS ........... 44
13.1 Application .............................................................................................................................. 44
13.2 Basics ...................................................................................................................................... 44
13.3 Adjustment to existing measuring method ......................................................................... 44
13.4 Preparing a sample ................................................................................................................ 45
13.5 Sample material ...................................................................................................................... 46
13.6 S ample size / originally weighted in quantity ...................................................................... 46
13.7 Drying temperature ................................................................................................................ 47
13.8 Recommendations / Guidelines ............................................................................................ 47
14 SERVICING, MAINTENANCE, DISPOSAL .................................................. 48
14.1 Cleaning .................................................................................................................................. 48
14.2 Servicing, maintenance ......................................................................................................... 48
14.3 Disposal ................................................................................................................................... 48
15 INSTANT HELP ............................................................................................. 49
4 DAB-BA-e-1813
1 Technical data
Data DAB 100-3 DAB 200-2
Item no./ Type - TDAB 200-2-A
Maximum load (Max) 110 g 200g
Readability (d) 0,001 g / 0,01% 0,01 g / 0,05%
Sample size 1 g – 110 g 1 g – 200 g
Recommended adjustment
weight, not added (class)
100g (F2) 200g (F2)
Warm-up time 2 h 30 min
Reproducibility
Weighed-in quantity 2 g
0,15 % 1,5 %
Reproducibility
Weighed-in quantity 10 g
0.02 % 0,3 %
Radiator type
Halogen (1 x 400 W)
Infrared (1 x 400 W) Factory option TDAB-A02-A
Temperature range
Models DAB 100-3 / DAB 200-2
40°C - 199°C
1°C steps selectable
Temperature range
Factory option TDAB-A02-A
40°C - 160°C
1°C steps selectable
Heating profiles
Standard drying
Fast drying
Soft drying
Linearity ± 0.003 g
Stabilization time (typical) 3 sec
Environmental conditions
5°C….+40°C ambient tem perature
max 80% air humidity non-condensing
DAB-BA-e-1813 5
Shutoff criterion
• Automatic switch off
(2mg weight loss in 45 s)
• Time-controlled switch off,
selectable 3 min – 99 min
• Manual switch-off by pressing stop key
Sample dishes included Ø 95 mm
Displays of result [%] moisture content
[%] dry content
[ g ] residual weight in grams
Internal memory Method memory Internal memory
Sample memory
Interface RS232
Dimensions (W x D x H) Housing 240 x 365 x 180 mm
Available
drying room
Ø 92 mm, 20 mm high
Net weight 4.8 kg
Electric Supply 220V 50 Hz AC
2 Declaration of Conformi ty
To view the current EC/EU Declaration of Conformity go to:
www.kern-sohn.com/ce
6 DAB-BA-e-1813
3 Appliance overview
Pos. Designation
1
Viewing panel
2 Heating hood
3 Halogen lamp
4 Heat shield
5 Sample dish
6
Windshield
7 Removal aid
8 Display
9 Keyboard
10
Adjustable foot
DAB-BA-e-1813 7
Pos. Designation
11 RS232C-interface connection
12
Bubble level
13 Fan
14 Mains connection socket
8 DAB-BA-e-1813
3.1 Keyboard overview
Button Function
• Call up menu
• Switch over display of result
• Cancel
• Start / finish drying and measuring process
• Taring
• Confirm / store settings
• Turn on/off
• Select parameter (forward)
• Increase digit
• Switch on background illumination of display
• Select parameter (backward)
• Reduce digit
• Switch off background illumination of display
DAB-BA-e-1813 9
3.2 Overview of display
Example: Working window during drying process
Pos. Designation
1
Status display - drying process enabled
2 Enabled heating profile flashes
Standard drying
Fast drying
Soft drying
3 Enabled switch-o ff crit er i on flashes
Automatic switch-off
Time controlled switch-off
Manual switch off
4 Previous drying time
5 Current temperature
6 Display in % moisture
7 Subtotal
10 DAB-BA-e-1813
4 Basic Information (General)
4.1 Proper use
The device purchased by you is designed for a fast and reliable determination of
material moisture in liquid, porous and solid materials by applying the method of
thermogravimetrics.
4.2 Improper Use
Impacts and overloading exceeding the stated maximum load (max) of the device,
minus a possibly existing tare load, must be strictly avoided.
This could cause damage to the integrated balance.
Never operate device in explosive environment. The serial version is not explosion
protected.
Changes to the unit's design are not permitted. This may lead to incorrect weighing
results, safety-related faults and destr uction of the appliance.
The unit may only be operated in accordance with the described default settings.
Other areas of use must be released by KERN in writing.
4.3 Warranty
Loss of warranty due to
• Our conditions in the operation manual are ignored
• The appliance is used outside the described uses
• Changing or opening instrument
• Mechanical damage and damage caused by media, liquids
• Natural wear and tear
• The appliance is improperly set up or incorrectly electrically connected
• The measuring system is overloaded
4.4 Monitoring of Test Resources
In the framework of quality assurance the measuring-related properties of the
integrated balance and, if applicable, the testing weight, must be checked regularly.
The responsible user must define a suitable interval as well as type and scope of this
test. Information is available on KERN’s home page (www.kern-sohn.com) with
regard to the monitoring of balance test substances and the test weights required for
this. In KERN's accredited DKD calibration laboratory test weights and balances may
be calibrated (return to the nati onal s tan dar d) fas t and at mo der ate cost.
DAB-BA-e-1813 11
5 Basic Safety Precautions
5.1 Pay attention to the instructions in the Operation Manual
Carefully read this operation manual before setup and
commissioning, even if you are already familiar with KERN balances.
All language versions contain a non-binding translation.
The original German is binding.
5.2 Symbols used in the operating instructions
Please pay due attention to information denoted by the signal
words CAUTION or WARNING as well as a warning
pictogram.
The signal word WARNING indicates a hazardous situation
where disregard of the safety information may result in fatal or
severe injury.
The signal word CAUTION indicates a hazardous situation
where disregard may result in minor injury.
NOTE (or LOOK OUT) indicates actions that may result in
damage to property.
This symbol indicates helpful information.
Call to action.
This prompts you to perform certain operations
12 DAB-BA-e-1813
5.2.1 Warning pictograms
High voltage
Chemical burn / corrosion
General hazard
Fire or explosion
Poisoning
Hot Surface
5.3 Personnel training
The instrument may only be operated and maintained by trained personnel.
DAB-BA-e-1813 13
5.4 Danger Information
!
The moisture analyser is used to analyse the moisture content of materials.
This instrument must be used exclusively for this purpose. Any other usage
may cause a risk to personnel, damage to the instrument or other material
damage.
!
The moisture analyser should be used mainly for the drying of aqueous
substances.
!
The moisture analyser may not be used in a hazardous area.
!
Do not use the moisture analyser in an explosive environment.
!
The operation and maintenance of the moisture analyser is restricted to
trained competent specialist staff.
!
Carefully read this operation manual before setup and commissioning, even if
you are already familiar with KERN in s truments.
!
Never make any modifications or design changes to the equipment
whatsoever. Always use original spare parts and accessories.
!
Make sure that liquids cannot pen
etrate the interior of the device, the terminals
at the rear of the device and the connected peripherals (such as printer, PC).
If you spill liquid on the device, disconnect it immediately.
Afterwards do not operate the moisture meter and have it checked by a
competent KERN stockist before any further use.
Hazards during and after measuring
!
Ensure correct installation of all components, see chap. 7.3
!
Careful when removing the sample. The sample itself, the sample dish and the
heating unit may be very hot.
!
Use the sample retainer at all times as it allows safe working and prevents
burns.
!
Individual parts of the case (e. g. the ventilation grids) may heat up
considerably during operation.
14 DAB-BA-e-1813
The moisture analyser operates using heat!
+ Maintain sufficient space in the environment of the instrument to
prevent heat build-up (distance from the instrument 20cm,
upwards 1m).
+ The heat extractor of the sample must never be covered, blocked,
taped up or altered in any other way.
+ Never place combustible materials on, under or next to the
instrument, as the environment of the instrument heats up to a
high temperature.
+ Careful when removing the sample. The sample itself, the sample
dish and the heating unit may be very hot.
Fire or explosion
+ Explosive, easily flammable samples and samples that go into a
chemical reaction when subjected to heat, may not be analysed
with the moisture analyser.
+ If in doubt, conduct a risk analysis.
+ Select a drying temperature for samples of this kind that is low
enough to prevent ignition or explosion.
+ Wear safety goggl es.
Substances that contain toxic or corrosive ingredients,
produce toxic gases when drying, cause irritation (eyes, skin,
airways), induce nausea or result in death
+ Sample materials emitting toxic substances must be dried with a
special extraction system in place. Create an environment that
prevents the inhalation of vapours hazardous to health.
Substances that liberate corrosive gases when heated up (such as
acids)
+ In that case, work with smaller sample amounts as the liberated
gases may condense on cooler casing parts and later cause
corrosion.
DAB-BA-e-1813 15
6 T ransport and storage
6.1 Testing upon acceptance
When receiving the appliance, please check packaging immediately, and the
appliance itself when unpacking for possible visible damage.
6.2 Packaging / return transport
Keep all parts of the original packaging for a possibly required
return.
Only use original packaging for returning.
Prior to dispatch disconnect all cables and remove
loose/mobile parts.
Secure all parts against shi fting and damage.
7 Unpacking, Setup and Commis si oning
7.1 Installation Site, Location of Use
The instrument is designed to achieve reliable weighing results under normal
conditions of use.
You will work accurately and fast, if you select the right location for your moisture
analyser.
On the installation site observe the following:
!
Remove explosion prone and easily flammable material in the immediate
vicinity.
Emerging vapours, sample dish and all parts of the sample chamber are hot!
!
Protect the instrument against direct draughts due to open windows and
doors.
!
Avoid extreme heat and temperature fluctuations e.g. due to installation next
to radiators.
!
Do not expose the instrument to extreme dampness for longer periods of time.
Non-permitted condensation (condensation of air humidity on the instrument)
may occur if a cold instrument is taken to a considerably warmer environment.
In this case, acclimatize the disconnected instrument for ca. 2 hours at room
temperature.
!
Avoid direct sunlight
!
The air humidity should be between 45% and 75%, non-condensing.
16 DAB-BA-e-1813
!
Sufficient distance from heat-sensitive materials in area around instrument.
!
Protect the instrument ag ai ns t hig h humidi ty, vapours and dust,
!
Major display deviations (incorrect weighing results) may be experienced
should electromagnetic fields (e.g. due to mobile phones or radio instruments),
static electricity accumulations or instable power supply occur. Change
location or remove source of interference.
!
Avoid static charging of the material to be weighed, weighing container and
windshield
!
Place the instrument on a firm, level surface.
!
Avoid jarring during weighing.
7.2 Unpacking and checking
Take the moisture analyser carefully out of its packaging, remove the plastic jacket
and install it at the designated work space.
7.2.1 Scope of delivery / serial accessories:
• Moisture analyser, see illustration chap. 2
• 50 sample dishes
• Power cable
• Operating manual
DAB-BA-e-1813 17
7.3 Placing
The moisture analyser is supplied part-assembled. Control whether the delivery is
complete immediately after unpacking the individual parts and assemble the separate
component parts according to the sequences.
1. Put heat shield into the sample chamber.
2. Place windshield in a way that the pin in the heat shield is aligned to the hole
in the heat shield.
3. Place removal aid into the windshield. Ensure that the lug lies exactly in the
groove of the windshield.
4. Attach the sample dish holder carefully and rotate it until it locks.
5. Put the sample dish on the removal aid.
2
4
5
3
18 DAB-BA-e-1813
7.4 Levelling
Precise alignment and stable installation are a precondition for repeatable results. To
compensate for minor unevenness or tilts of the base, level the instrument.
Level instrument with foot screws until the air bubble of the
water balance is in the prescribed circle.
Check levelling regularly
DAB-BA-e-1813 19
7.5 Mains connection
Power supply is provided via the supplied mains cable.
Check, whether the voltage acceptance on the device is set correctly.
Do not connect the appliance to the power grid unless the information
on the instrument (sticker) matches the local mains voltage.
Do not eliminate the protective effect by using an extension lead
without earth terminal. For power supplies from power grids without
earth terminals call a specialist to establish equivalent protection
according to the relevant installation regulations.
The mains plug must be accessible at any time.
Prior to commissioning check the mains cable for damage.
Place the cable in a way that it cannot be damaged or handicaps
the measuring process.
Important:
Does the rating match the standard local mains current?
Do not connect if mains voltages are different!
If matching, connect the moisture analyser.
7.6 Switching on and off
Turn on appliance by pressing the ON/OFF key.
The display lights up and the equipment conducts a self-test. Wait
until basic configuration appears.
To switch off press the ON/OFF button, the display disappears.
20 DAB-BA-e-1813
7.6.1 Initial Commissioning
In order to receive precise weighing results from electronic balances, the instrument
unit must have reached its operating temperature (see warming-up time chapter 1).
For this warm-up period the integrated balance must be connected to the power
supply.
The accuracy of the integrated balance depends on the local acceleration of gravity.
Please observe hints in chapter Adjustment.
7.7 Connection of peripheral devices
Before connecting or disconnecting of additional devices (printer, PC) to the data
interface, always disconnect the moisture analyser from the power supply.
Only use accessories and peripheral devices by KERN, as they are ideally tuned to
the appliance.
DAB-BA-e-1813 21
8 Adjustment
8.1 Weight adjustment
The weight adjustment of the integrated balance is not absolutely necessary for a
correct moisture determination, as this measurement is only carried out relatively.
The instrument calculates the weight of the sample before and after the drying
process and the moisture content is determined with help of the ratio between wet
weight and dry weight.
The instrument however should be adjusted, if this is required due to the quality
system used by you.
Procedure:
• Observe stable environmental conditions.
A warming up time (see chapter
1) is required for stabilization.
• Carry out adjustment with placed sample dish.
Ensure that no objects are
within the sample dish.
•
Carry out adjustment as near as possible to the balance’s maximum
weight (recommended adjustment weight see chap. 1).
Info about test
weights can be found on the Intern et at : http://www.kern-sohn.com.
Press and keep pressed until „CAL“ is displayed.
Wait until the weighed value for the required adjustment weight appears
flashing.
Sample indication DAB 100-3
22 DAB-BA-e-1813
Put the required adjustment weight carefully into the centre of the sample dish.
Adjustment is carried out automatically.
After successful adjustment the balance automatically returns to weighing
mode, „100,000 g“ will be displayed. Take away adjustment weight.
Wait until „0.000 g“ appears.
DAB-BA-e-1813 23
8.2 Calibrate / adjust temperature of the heating module
8.2.1 Temperature calibr ation
We recommend performing occasional tests of the instrument’s temperature value,
using the optional temperature calibration set KERN DAB-A01.
Before you do this, allow the device to cool down for at least 3 hours after the last
heating phase.
Preparation:
Switch off moisture analyser
Install temperature calibration set as per illustration
Turn on moisture analyser
24 DAB-BA-e-1813
Set test parameters:
After pressing the first ident number <0> will be displayed.
Using arrow keys select e.g. ident number <1> and confirm by
. The currently set heating profile flashes.
Using arrow keys select heating profile <SOFT> and confirm by
.
The currently set heating profile and switch-off criter i on fl ashes.
Use the arrow keys to select switch-off criterion <MANUAL>.
DAB-BA-e-1813 25
Confirm by , the currently set drying temperature flashes.
Use the arrow keys to enter the desired test temperature. For the
first or the first two digits select a value and confirm by .
Using arrow keys select the desired value for the last digit.
Confirm input by .
26 DAB-BA-e-1813
Begin temperature calibration:
Switch on temperature calibration set.
Close heating hood and press . The instrument will be automatically
heated to the set temperature. The cur r ent temperature and the elaps ed ti me
will be indicated in the display.
After approx. 15 minutes finish by . Compare the temperature value of
the moisture analyser with that of the temperature calibration set. At a
difference of ±5°C we recommend to adjust the temperature, see following
chapter.
8.2.2 Temperature adju stm ent
If the admissible deviation is exceeded / not reached during temperature calibration
the temperature of the instr ument can be adj u s ted as des cr i bed bel o w.
1. Switch off instrument.
2. Press , quickly release, then press and at the same time.
„8.2X“ will be displayed. If not, separate device from power supply and restart
step two.
3. Adjust temperature using arrow keys . Each time you press the
button the temperature will be increased or reduced by 1°C.
4. Confirm input by .
DAB-BA-e-1813 27
9 Carry out your first measurem e nt
We recommend to carry out a first simple measurement in order to get acquai nte d
with the device and the displays. Here you work with the ex-factory set drying
parameters (standard drying 120°C, automatic switch off).
In order to obtain exact results, the instrument must have reached its
operating temperature (see warm-up time chap. 1). For this warm-up time
the instrument must be connected to the power supply.
Place into the sample dish a dry piece of paper
Place removal aid with the sample dish on the sample dish retainer. Make
sure that the sample dish is resting flat on the sam ple dish retainer. Always
work with a removal aid as this will enable safe working and prevent burns.
Close heating hood and tare with .
Open heating hood.
Pour approx. 3 g of water on the paper in the sample dish.
Wait until the stability monitor „o“ goes out.
Close heating hood.
Start the drying process by .
The status display indicates the enabled drying process
You can watch the drying process on the display screen.
The current temperature, lapsed time as well as the current interim result will
be continuously updated and displayed.
The icons of the enabled heating profile and the switch-off criterion are
flashing.
Using the display con be switched over to the different displays of
results.
28 DAB-BA-e-1813
When drying is finished, an acoustic signal will sound. The result will be
displayed.
Using the display of results can be switched over into
% moisture % dry content residual weight in grams.
Open the heating hood and remove the sample with the help of the removal
aid. Caution: Sample dish and all parts of the sample chamber are hot!
Using the result in the display will be deleted. The display returns to
weighing mode. The device is now ready for another measurement.
DAB-BA-e-1813 29
10 Define drying parameters
In chapter 9 you have already carried out a first measurement with the factory
settings.
The device provides a great variety of setting options that allow you to adapt a drying
method to your sample.
Three heating profiles (standard drying, soft drying, fast drying) and three switch-off
criteria (time-controlled, automatic, manual) can be selected.
1. Enter ident number for drying method
16 memory locations, which can be simply called up and started as necessary under
the saved ident number (0 –F), are available for complete drying methods.
After pressing the first ident number <0> will be displayed.
This memory location is provided for the factory setti ng s (s tandar d dr y i ng
120°C, automatic swit ch-off) and cannot be changed.
Use the arrow keys to select the desired ident number and
confirm by . The currently set heating profile flashes.
30 DAB-BA-e-1813
2. Set heating profile
Using arrow keys select required heating profile and confirm by
.
Options:
Standard drying
Fast drying
Soft drying
Standard drying <STANDARD>
This heating profile is suitable for
most samples.
The sample will be
heated up to the set drying
temperature and will be kept
constantly at this temperature.
Selectable 40°C -199°C
DAB-BA-e-1813 31
Fast drying <FAST>
This heating profile is suitable for
samples with high moisture content
(such as liquids).
The temperature will initially rise very
fast after the start and for a short time
will exceed the set drying temperature
by 30%. That way the latent heat will be
compensated, thereby accelerating the
drying process.
Then the temperature is controlled down
to the set value.
Soft drying <SOFT>
This heating profile is suitable for soft
drying of substances prone to skin
formation (such as easily liquefiable
substances
or substances containing
sugar).
Skin formation affects the
evaporation of trapped moisture. The
temperature will be increased
continuously and will not reach the set
drying temperature before the so-called
ramp duration has elapsed.
32 DAB-BA-e-1813
3. Se lecting switch-off criterion
A switch-off criterion defines under which conditions the device should cancel the
drying process. Switch-off criteria save continuous time controls and manual
cancelling of drying processes. Furthermore they ensure that measurement s ar e
always finished under the same conditions, thereby providing repeatable
measurements.
After acknowledgement of the selected heating profile by , the currently
set heating profile and switch-off criterion flashes.
Using arrow keys select required switch-off criterion and confirm
by .
Selectable settings suitable as switch-off criteria include:
<AUTO>
Automatic switch off
(2mg weight loss in 45 s)
This switch-off criterion is based on a
weight loss per time unit. As soon as the
medium weight loss drops below the
desired value per unit of time, the
measurement will be finished
automatically.
<TIMING>
Time-controlled switch off,
selectable 3 min – 99 min
When this switch-off criterion is selected
the measurement will continue until the set
drying time has lapsed
<MANUAL>
Manual switch-off by pressing stop key
DAB-BA-e-1813 33
4. Set drying temperature
After acknowledgement of the selected switch-off criteri on by , the
currently set drying temperature is flashing.
Using arrow keys , select the desired value for the first or the first
two digits and confirm by .
Using arrow keys select the desired value for the last digit.
Confirm input by .
If as switch-off criteri on <AUTO> or <MANUAL> is selected, the parameter
setting is finished here. All parameter settings will be applied to a subsequent
drying process and displayed on screen. All settings are stored under the ident
number <1> until a new method is allocated to the ident number.
<AUTO>
<MANUAL>
When <TIMING> is selected, the display of setting the drying period of time is
flashing, see step „5“.
34 DAB-BA-e-1813
5. Setting the drying period for time-controlled switching-off
After acknowledgement of the drying temperature by , the currently set
drying period is flashing.
Using arrow keys , select the desired value for the first digit and
confirm by , the next digit is flashing.
Using arrow keys , select the desired value for the next digit and
confirm by , the next digit is flashing. Repeat this procedure for all digits.
Confirm input by . All parameter settings will be applied to a subsequent
drying process and displayed on screen. All settings are stored under the ident
number <1> until a new method is allocated to the ident number.
DAB-BA-e-1813 35
11 Carrying out drying and measuring processe s
In order to obtain exact results, the instrument must have reached its
operating temperature (see warm-up tim e chap. 1). For this warm-up
time the instrument must be connected to the power supply.
Either invoke a drying method stored beforehand or set drying
parameters as specified in chapter 10.
After pressing the button the first ident number <0> of a drying method
will be displayed.
Use arrow keys to select a desired ident number o f a dryi ng
method and confirm by . The currently set heating profile flashes.
36 DAB-BA-e-1813
Confirm all flashing indicated par a met er s one by one by or change
them as necessary.
Open heating hood and place removal aid with an empty sample dish on the
sample dish retainer. Make sure that the sample dish is resting flat on the
sample dish retainer. Always work with a removal aid as this will enable safe
working and prevent burns.
Close heating hood and tare with .
Open heating hood.
Distribute sample evenly on the sample tray. A practical sample amount is
typically approx. 3- 5 g.
Close heating hood.
Start drying process by .
The status display indicates the enabled drying process
You can watch the drying process on the display screen.
The current temperature, lapsed time as well as the current interim result will
be continuously updated and displayed.
The icons of the enabled heating profile and the switch-off criterion are
flashing.
Using the display con be switched over to the different displays of
results.
DAB-BA-e-1813 37
When drying is finished, an acoustic signal will sound. The result will be
displayed.
Using the display of results can be switched over into
% moisture % dry content residual weight in grams.
Open the heating hood and remove the sample with the help of the removal
aid. Caution: Sample dish and all parts of the sample chamber are hot!
Using the result in the display will be deleted. The display returns to
weighing mode. The device is now ready for another measurement.
38 DAB-BA-e-1813
12 RS 232 interface
Condition:
The following conditions must be met to provide successful communication between
the moisture analyser and the printer.
Disconnect moisture analyser from the power supply and connect to the
appliance interface with a suitable cable. Faultless operation requires an
adequate KERN interface cable.
Communication parameters of the RS 232 interface of moisture analyser and
printer must match.
12.1 Technical data
Connection 9 pin d-subminiature bushing
Pin3 - TxD
Pin5 - GND
Baud-Rate 1200 / 2400 / 4800 /9600 selectable
Parity 7bits / 2 stop bits
12.2 Setting the baud rate
Press ,then release quick und press fast. The current baud rate is
indicated.
Using arrow keys select baud rate .
Confirm with .
DAB-BA-e-1813 39
12.3 Print out protocol:
To edit a protocol press and keep it pressed until “PRINT“ appears. The
display changes automatically to „L-E“.
Acknowledge with . The protocol of the measurement carried out as last
is displayed under the ident number „1“. The instrument stores the last fiv e
protocols (ident number 1 -5). With every new measurement, the ident number
One will be overwritten.
Use the arrow keys to select the desired ident number and
confirm by . The protocol will be edited.
40 DAB-BA-e-1813
Sample protocol (KERN YKB-01N):
MOISTURE DETERMINATION (1)
Protocol ident number (1)
Machine Type: DAB 100-3
Gerätetyp
Heating Mode: STANDARD
Selected heating profile
Stop Mode: AUTO STOP
Selected switch-off criterion
Heating Temp: 120 °C
Drying temperature
Time el apsed: 03:52
Overall duration of drying process
Wet W: 10.145 g
Start weight
Dry W: 10.010 g
Residual weight
Moisture: 1.32 %M
Final result in % moisture
12.4 Continuous data transmission
Settings:
Switch on the device, pressing key. During the auto test, press ,
<C---1> will be displayed.
Press to confirm. The first menu item with the current setting will be
displayed.
DAB-BA-e-1813 41
Choose the data transmission type, pressing , switch it on/off using the
navigation buttons .
residual mass in grams
% humidity
% solid content
42 DAB-BA-e-1813
Press to confirm. The indication used to set the data transmission
cycle, i.e. <C---2> will be displayed.
Press to confirm and set the required data transmission cycle using the
navigation buttons (you can select from: 1, 2, 5, 10, 30, 60, 120,
300, 600 s).
Confirm your choice, pressing , wait until zero is displayed.
DAB-BA-e-1813 43
Activation of continuous data transmission
Press button and hold it until <t> is displayed (if you get <PRINT>, keep
the button pressed). Wait until zero is displayed.
This is the starting/finishing time of continuous data transmission when the
measurement is started/completed.
Using our data transmission software, i.e. Balance connection (KERN SCD
4.0) the displayed values will be sent to the computer as per the pre-defined
data transmission cycle.
Simultaneously, the drying characteristics can be presented in a graphic form. It
presents the drying progress in real time and can be used for result checking
and evaluation.
44 DAB-BA-e-1813
13 General information concerning moisture analysis
13.1 Application
In all cases where moisture is added to or removed from products, a fast
determination of the moisture content is of enormous importance. For countless
products the moisture content is not only a quality feature but also an important cost
factor. Very often fixed limits for moisture content apply to the trade in industrial or
agricultural goods as well as chemical or food products which are defined by terms of
delivery and general standards.
13.2 Basics
Moisture does not only mean water but includes all substances that evaporate when
heated up. In addition to water this includes,
Fats
Oils
Alcohol
Solvents
etc...
There are various methods to analyse moisture in a product.
KERN DAB uses a method called thermogravimetrics. In accord with this method, the
sample is weighed before and after heating, determining the material moisture by
looking at the difference.
The conventional drying chamber method follows the same principle, with the
exception that this method requires a considerably longer measuring period. . In
accord with the drying chamber method, the sample is heated from the outside to the
inside by a hot air current, so as to remove the moisture. The radiation applied in the
KERN DAB penetrates mainly the sample in order to be transformed inside it into
heat energy that is, warming from the inside to the outside. A minor amount of
radiation is reflected by the sample, a reflection that is less in dark samples than in
light-coloured ones. The depth of penetration of the radiation depends on the
permeability of the sample. In samples of low permeability the radiation only
penetrates the outer layers of the sample, possibly resulting in imperfect drying,
incrustation or burning. For that reason the preparation of a sample is of great
importance.
13.3 Adjustment to existing measuring method
KERN DAB frequently replaces a different drying method (such as drying cabinet) as
easier operation achieves shorter measuring periods. For that reason the
conventional measuring method must be matched to the KERN DAB in order to
achieve comparable results.
• Performing parallel measurements
Lower temperature setting for KERN DAB than for drying cabinet method
• Result of KERN DAB does not match reference
- Repeat meas ur em ent with changed temperature setting
- Vary shutoff criterion
DAB-BA-e-1813 45
13.4 Preparing a sample
Prepare one sample at a time for measuring. This prevents the sa m ple fro m
exchanging moisture with its surroundings. If several samples have to be taken at the
same time, they should be packed in airtight boxes so that they do not undergo
changes during storage.
To receive reproducible results, spread the sample thinly and evenly on a sample
dish.
Patchy spreads will produce inhomogeneous heat distribution in the sample to be
dried resulting in incomplete drying and increased measuring time. Sample clusters
generate increased heating of the upper layers resulting in combustion or
incrustation. The high layer thickness or possibly arising incrustation makes it
impossible for the moistur e to escape from the sample. Due to this residual moi sture,
measured results calculated in this way will not be comprehensible or reproducible.
Preparing a sample from solids:
• Spread powdery or grainy samples evenly on the sample dish.
• Grind coarse samples using a mortar or a shredder. When grinding the sample avoid
any heat supply as this may cause loss of moisture.
Preparing a sample from liquids:
For liquids, pastes or melting samples we recommend to use a glass fiber filter. The glass
fiber filter has the following advantages:
• even distribution thanks to capillary attraction
• no formation of droplets
• fast evaporation due to a greater surface
46 DAB-BA-e-1813
13.5 Sample material
Easy to determine are usually samples with the following characteristics:
Grainy to powdery, pourable solids
Thermally stable materials, emitting the moisture to be determined easily
without other substances evaporating at the same time
Liquids that vaporize to leave a dry substance without developing a film
Difficult to determine may be samples tha t are :
Glutinous or sticky
Become incrusted easily or tend to form a film
Decompose easily under the influence of heat or emit various elements
13.6 Sample size / originally weighted in quantity
Drying times, as well as achievable accuracy, are significantly influenced by sample
distribution. In the course of this arise two opposed requirements:
The lighter the originally weighted in quantity, the easier it is to achieve shorter drying
times. However, the heavier the originally weighted in quantity, the more accurat e a
result.
DAB-BA-e-1813 47
13.7 Drying temperature
The temperature has to be selected in a manner that the sample is not decomposed
or changes its chemical structure. But on the other hand if the temperature is too low,
drying time may be unnecessarily extended.
Bear in mind the following factors when setting the drying temperature:
Surface of the sample:
Compared with powdery or grainy samples, liquid and spreadable samples have a
smaller surface for the transmission of heat energy.
The use of a glass fibre filter improves the heat application.
Colour of sample:
Light-coloured samples reflect more heat radiation than dark ones and therefore
require a higher drying temperature.
Availability of volatile substances:
The better and faster the water or other volatile substances can be disposed, the
lower a drying temperature is required. If water is difficult to get to (e. g. in
synthetics), it has to be calcined at high temperatures (the higher the temperature,
the higher the water vapour pressure).
Results equivalent to other moisture analysing methods (e. g. drying chamber) can
be achieved by experimentally optimising the setting parameters such as
temperature, heating level and shutoff criteria.
13.8 Recommendations / Guidelines
Prepare standard sample:
Crush sample, as required, and spread it evenly in the aluminium dish.
Prepare special samples:
For sensitive or hard to spread test materials (e. g. mercury) a glass fibre filter
is available for use.
Spread sample evenly on glass fibre filter and cover is with a second glass
fibre filter.
The glass fibre filter is also useful as a protection when splashing materials
are dealt with (each splash falsifies the final result).
You will find examples taken from actual use in our application manual, available
from the KERN home page (www.kern-sohn.com).
48 DAB-BA-e-1813
14 Servicing, maintenance, disposal
Before any maintenance, cleaning and repair work disconnect the
appliance from the oper ati ng vol tage.
14.1 Cleaning
+
Only carry out cleaning tasks when the equipment has cooled down.
Open heating hood and remove all parts in the right order and clean.
Please do not use aggressive cleaning agents (solvents or similar agents), but a
cloth dampened with mild soap suds. Ensure that no liquid penetrates into the
device. Polish with a dry soft cloth.
Loose residue sample/powder can be removed carefully with a brush or manual
vacuum cleaner.
14.2 Servicing, maintenance
The appliance may only be opened by trained service technicians who are
authorized by KERN.
Ensure that the balance is regularly calibrated, see chap. Monitoring of test
resources.
14.3 Disposal
Disposal of packaging and appliance must be carried out by operator according
to valid national or regional law of the location where the appliance is used.
DAB-BA-e-1813 49
15 Instant help
Possible causes of errors:
In case of an error in the program process, briefly turn off the balance and disconnect
from power supply. The weighing process must then restart from the beginning.
Fault Possible cause
Display is not lit up.
• The appliance is not switched on.
• The mains supply connection has been
interrupted (mains cable not plugged in/faulty).
• Power supply interrupted.
• Fuse has blown
The display does not change
when a sample is being loaded
• Sample dish / dish holder is fitted incorrectly.
The weight display changes
constantly / the stability display
does not appear.
• Sample dish has contact with windshield or
heating hood.
• Draught/air movement
• Table/floor vibrations
• Electromagnetic fields / static char g ing (choose
different location/switch off interfering device if
possible)
Incorrect measuring res ul t
• Check adjustment
• No resetting to zero before loading the sample
Measurement is taking too
long
• Incorrect shut-down criteria set
Measurement is not
reproducible
• Sample is not homogenous
• Drying time is too short
• Drying temperature too high (e.g. oxidation
sample material, boiling point of sample
exceeded)
• Temperature sensor soiled or defective
Drying does not start
• Heating hood open
• The mains supply connection has been
interrupted (mains cable not plugged in/faulty).
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