KERN MLB50-3 User manual

MLB50-3-BA-defsi-0310
28
GB KERN MLB50-3
Version 1.0 05/2003
Operating Instructions
Moisture Analyzer
Table of contents:
1Technical data ________________________________________________________ 30
2Declaration of conformity _______________________________________________ 31
3Fundamental information (general) _______________________________________ 32
3.1 Intended use ___________________________________________________________ 32
3.2 Inappropriate use_______________________________________________________ 32
3.3 Protective measures _____________________________________________________ 32
3.4 Warning ______________________________________________________________ 32
3.5 Guarantee _____________________________________________________________ 33
3.6 Monitoring the test substances ____________________________________________ 33
4Fundamental safety information __________________________________________ 34
4.1 Observe the information in the operating instructions ________________________ 34
4.2 Staff training __________________________________________________________ 34
5Transport and storage __________________________________________________ 34
5.1 Acceptance check _______________________________________________________ 34
5.2 Packaging _____________________________________________________________ 34
6Unpacking, installation and commissioning_________________________________ 35
6.1 Place of installation, place of use __________________________________________ 35
6.1.1 Installation__________________________________________________________________ 35
6.1.2 List of items supplied _________________________________________________________ 35
6.2 Mains supply __________________________________________________________ 36
6.3 Connecting peripheral equipment _________________________________________ 36
6.4 Initial start-up _________________________________________________________ 36
6.5 Adjustment ____________________________________________________________ 37
6.6 Adjusting______________________________________________________________ 37

MLB50-3-BA-defsi-0310 29
7Moisture determination _________________________________________________ 38
7.1 Use ___________________________________________________________________ 38
7.2 Sample material ________________________________________________________ 38
7.3 Sample preparation _____________________________________________________ 38
7.4 Drying temperature _____________________________________________________ 39
7.5 Application table (recommendations) ______________________________________ 40
7.6 Temperature calibration / adjustment______________________________________ 41
8Setting the parameters __________________________________________________ 42
8.1 Temperature correction on “SubSt“ test object ______________________________ 43
8.1.1 Setting the correction factor ____________________________________________________ 44
8.2 Modes “modE“ _________________________________________________________ 45
8.3 Maximum drying time “IntEr“ ___________________________________________ 46
8.4 Drying temperature “tEmP“______________________________________________ 46
8.5 Data query time interval “Strob“ __________________________________________ 46
9Operation ____________________________________________________________ 46
9.1 Control elements _______________________________________________________ 46
9.1.1 Overview of the keyboard______________________________________________________ 46
9.1.2 Overview of the display screen __________________________________________________ 47
9.2 Operation _____________________________________________________________ 47
9.2.1 Weighing___________________________________________________________________ 47
9.2.2 Taring ( key) ___________________________________________________________ 48
9.3 Determination of humidity _______________________________________________ 49
9.3.1 Test accuracy________________________________________________________________ 50
10 RS232 serial interface ________________________________________________ 51
10.1 Print format ___________________________________________________________ 51
10.2 Changing languages_____________________________________________________ 53
11 Maintenance, upkeep, disposal _________________________________________ 53
11.1 Cleaning ______________________________________________________________ 53
11.2 Maintenance, upkeep____________________________________________________ 53
11.3 Disposal _______________________________________________________________ 53
12 Troubleshooting _____________________________________________________ 54

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1 Technical data
KERN MLB 50-3
Maximum load rating (max.) 50 g
Minimum for drying 0.02 g
Temperature range 50°C-160°C
Setting the temperature in 1°C stages
Pre-heating stage (boost) No
Read off (d) 0.001g /0.01%
Repeatability in weighing
(=standard divergence)
0.001 g
Repeatability during drying
(=standard divergence)
Initial weight 1g
Initial weight 10g
0.2%
0.02%
Please note: recommended minimum weight 2g
Adjusting weight not added 50g (F2)
Ambient conditions 15°C ... 35°C ambient temperature
max. 80% air humidity; not condensing
Shutdown criterion Automatic:
End of drying if the results do not alter during 3
strobe intervals (=heating intervals).
If a time limit has been set drying will shut down
after this period expires.
Adjustable strobe interval: 1 s – 59 s
Manual:
According to set time (10 min to 590 min [=9h 50
min]) (without strobe interval)
Display after drying % humidity = weight reduction
(=residual weight/start weight)*100%
% dry matter = residual weight
(=weight loss/start weight)*100%
% ATRO
(=weight loss/residual weight)*100%
Details are not possible in grammes during drying.
Including sampling trays 10
Protective hood no
Type of projector 2 halogen quartz projectors
200 watts each
Display LED display/ character height 15 mm
3 displays for: - drying status
(depending on configuration)
- temperature
- drying time

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2 Declaration of conformity
KERN & Sohn GmbH
Ziegelei 1
D – 72336 Balingen
E-Mail: [email protected]
Tel: 0049-[0]7433- 9933-0
Fax: 0049-[0]7433-9933-149
Internet: www.kern-sohn.com
Declaration of conformity
Declaration of conformity for apparatus with CE mark
Konformitätserklärung für Geräte mit CE- Zeichen
Déclaration de conformité pour appareils portant la marque CE
Declaración de conformidad para aparatos con disitintivo CE
Dichiarazione di conformitá per apparecchi contrassegnati con la marcatura CE
English We hereby declare that the product to which this declaration refers conforms with the
following standards.
Deutsch Wir erklären hiermit, dass das Produkt, auf das sich diese Erklärung bezieht, mit den
nachstehenden Normen übereinstimmt.
Français Nous déclarons avec cela responsabilité que le produit, auquel se rapporte la présente
déclaration, est conforme aux normes citées ci-après.
Español Manifestamos en la presente que el producto al que se refiere esta declaración est´´a de
acuerdo con las normas siguientes
Italiano Dichiariamo con ciò che il prodotto al quale la presente dichiarazione si riferisce è con-
forme alle norme di seguito citate.
Moisture Balance: KERN MLB 50-3
Mark applied EU Directive Standards
73/23EEC Low voltage EN 60950
89/336EEC EMC EN 50081-1
EN 50082-1
Date: 01.05.2003 Signature:
Gottl. KERN & Sohn GmbH
Management
Gottl. KERN & Sohn GmbH, Ziegelei 1, D-72336 Balingen, Tel. +49-[0]7433/9933-0,Fax +49-[0]7433/9933-149

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3 Fundamental information (general)
3.1 Intended use
The balance you have acquired serves to determine the weighing value of the mate-
rial to be weighed. It is intended to be used as a “non-automatic“ balance, i.e. the
material to be weighed is manually and carefully placed in the centre of the weighing
plate. The weighing value can be read off after a stable weighing value has been ob-
tained.
3.2 Inappropriate use
Do not use the balance for dynamic weighing. In the event that small quantities are
removed or added to the material to be weighed, incorrect weighing results can be
displayed due to the “stability compensation“ in the balance. (Example: Slowly drain-
ing fluids from a container on the balance.)
Do not leave a permanent load on the weighing plate. This can damage the measur-
ing equipment.
Be sure to avoid impact shock and overloading the balance in excess of the pre-
scribed maximum load rating (max.), minus any possible tare weight that is already
present. This could cause damage to the balance.
Never operate the balance in hazardous locations. The series design is not explo-
sion-proof.
Structural alterations may not be made to the balance. This can lead to incorrect
weighing results, faults concerning safety regulations as well as to destruction of the
balance.
The balance may only be used in compliance with the described guidelines. Varying
areas of application/planned use must be approved by KERN in writing.
3.3 Protective measures
The moisture analyser of Safety Class 1 may only be connected through a carefully
installed socket with protective earth (PE). The protective effect must not be can-
celled out by the use of an extension lead without earth wire. For power supplies from
mains not provided with a protective earth, an equivalent protection meeting the valid
installation regulations must be provided by a qualified electrician.
3.4 Warning
Individual parts of the housing (e.g. ventilation grille ...) can become very hot during
operation. Avoid touching the apparatus except by the handles provided for this pur-
pose.
Sample materials which produce corrosive vapours (e.g. acids) can cause problems
of corrosion of components. The MLB50-3 should be used primarily for drying hy-
drous substances.
The MLB50-3 must not be used to analyse highly inflammable samples which pre-
sent an explosion hazard.

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3.5 Guarantee
The guarantee is not valid following
- non-observation of our guidelines in the operating instructions
- use outside the described applications
- alteration to or opening of the device
- mechanical damage and damage caused by media, liquids
- natural wear and tear
- inappropriate erection or electric installation
- overloading of the measuring equipment
3.6 Monitoring the test substances
The metrology features of the balance and any possible available adjusting weight
must be checked at regular intervals within the scope of quality assurance. For this
purpose, the answerable user must define a suitable interval as well as the nature
and scope of this check. 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. Test weights and balances can be adjusted quickly and at
a reasonable price in KERN’s accredited DKD calibration laboratory (return to na-
tional normal).

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4 Fundamental safety information
4.1 Observe the information in the operating instructions
Please read the operating instructions carefully before erecting and commissioning,
even if you already have experience with KERN balances.
4.2 Staff training
The device may only be operated and looked after by trained members of staff.
5 Transport and storage
5.1 Acceptance check
Please check the packaging immediately upon delivery and the device during un-
packing for any visible signs of external damage.
5.2 Packaging
Please retain all parts of the original packaging in case it should be necessary to re-
turn items at any time.
Only the original packaging should be used for return consignments.
Before despatch, disconnect all attached cables and loose/movable parts.
Apply any intended transport security devices. Secure all parts, e.g. glass windshield,
weighing plate, power unit etc., to prevent slipping and damage.

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6 Unpacking, installation and commissioning
6.1 Place of installation, place of use
The balance is constructed in such a way that reliable weighing results can be
achieved under normal application conditions.
By selecting the correct location for your balance, you will be able to work quickly and
precisely.
Therefore please observe the following at the place of installation:
- Place the balance on a firm, level surface;
- Avoid extreme heat as well as temperature fluctuation caused by installing
next to a radiator or in the direct sunlight;
- Protect the balance against direct draughts due to open windows and doors;
- Avoid jarring during weighing;
- Protect the balance against high humidity, vapours and dust;
- Do not expose the device to extreme dampness for longer periods of time.
Inadmissible bedewing (condensation of air moisture on the device) can occur
if a cold device is taken into a significantly warmer environment. In this case,
please acclimatise the device for approx. 2 hours at room temperature after it
has been disconnected from the mains.
- Avoid static charging of the material to be weighed, weighing container and
windshield.
Major display deviations (incorrect weighing results) are possible if electromagnetic
fields occur as well as due to static charging and instable power supply. It is then ne-
cessary to change the location.
6.1.1 Installation
Use the foot screws to level the balance until the air bubble in the bubble level is in
the prescribed circle.
6.1.2 List of items supplied
Standard accessories: Available optional accessories:
- Balance including humidity - Aluminium trays (item no.:MLB-A01)
identifier attachment - Glass fibre filter (item no.:RH-A02)
- Tray holder - Temperature calibration set
- 10 sampling trays - (item no.:MLB-A03)
- Mains cable

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6.2 Mains supply
A mains cable is used for the electric power supply.
Please check whether the balance voltage intake has been set correctly. The balance
may only be connected to the mains supply if the details on the balance (label) and
the customary on-site mains voltage are identical.
Important:
Does the designation (220 V 50 Hz) comply with the customary on-site mains voltage?
- Do not connect if there are differences in the mains voltage!
- The balance may be connected if in compliance.
6.3 Connecting peripheral equipment
The balance must be disconnected from the mains before connecting or disconnect-
ing additional equipment (printer, PC) to or from the data interface.
Only use KERN accessories and peripheral equipment with your balance. These
have been ideally coordinated to your balance.
6.4 Initial start-up
The accuracy of the balance depends on the local acceleration of the fall.
Please be sure to observe the information in the chapter on “adjusting”.
Use the main switch (above the power plug) to switch on the balance. ”tEmP “
will appear.
You have two choices:
1. Press the key, the balance will run through a ”tEst “ mode. “0.000 “ will appear
on the display screen after a few seconds. A short warm-up period of approx. 10
minutes is advisable for stabilisation purposes.
2. It is possible to start up a pre-heating process that pre-heats the weighing region
to a reasonable drying process temperature. This pre-heating process is only practi-
cal before initial drying if there are to be several consecutive drying procedures.
This procedure can be triggered whilst “tEmP “ is on the display screen by operating
the key. The balance switches automatically to weighing mode after a few
minutes.
Use the key to enter weighing mode.

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6.5 Adjustment
As the acceleration value due to gravity is not the same at every location on earth,
each balance must be coordinated – in compliance with the underlying physical
weighing principle - to the existing acceleration due to gravity at its place of location (
only if the balance has not already been adjusted to the location in the factory). This
adjustment process must be carried out during the initial start-up, after change in lo-
cation and variation of surrounding temperature. It is also recommendable to adjust
the balance periodically during weighing operation in order to obtain exact measured
values.
6.6 Adjusting
Using a precision weight, the accuracy of the balance can be checked at any time
and adjusted.
Method of approach when adjusting:
Ensure sound ambient conditions.
Use the main switch (above the power plug) to switch on the balance. ”tEmP “ will
appear on the display screen. Press the key, the balance will run through a ”tEst
“ mode. “0.000 “ will appear on the display screen after a few seconds. A short warm-
up period of approx. 10 minutes is advisable for stabilisation purposes.
Start up the adjusting process by operating the key. “------------- “ will appear on
the display screen for a few seconds.
The key must be pressed whilst “-------------“ is on the display screen.
Subsequently, “noCAL“ will appear on the display screen . “-LoAd-“ will appear on
the display screen after a few seconds, followed by the nominal value of the adjusting
weight.
The calibration process can be aborted during this period by pressing the key.
Now apply the adjusting weight and calibration will take place (please wait).
“ CAL “ will appear on the display screen, followed by ” rELoAd “ a few seconds
later.
Now remove the adjusting weight from the weighing plate.
The adjusting process is completed. The adjusting weight can be re-applied in order
to check the calibration. If the displayed value is not correct, adjusting should be re-
peated.