KERN EMB-V User manual

KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: [e-mail]
Phone: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Operating instructions
Density Scale
KERN EMB-V
Version 2.0
01/2013
GB
EMB-V-BA-e-1320

EMB-V-BA-e-1210
2
GB
KERN EMB-V
Version 2.0 01/2013
Operating instructions
Density Scale
Contents
1Technical data ................................................................................................ 4
2Appliance overview ....................................................................................... 5
2.1 KERN EMB 200-3V with installed density kit KERN YDB-01...................................... 6
2.2 KERN EMB 2000-2V with installed density kit KERN YDB-02.................................... 7
2.3 Keyboard overview .................................................................................................... 8
2.3.1 Numeric entry ............................................................................................................................. 8
3Basic Information (General) .......................................................................... 9
3.1 Proper use................................................................................................................. 9
3.2 Improper Use............................................................................................................. 9
3.3 Warranty.................................................................................................................... 9
3.4 Monitoring of Test Resources...................................................................................10
4Basic Safety Precautions ............................................................................ 10
4.1 Pay attention to the instructions in the Operation Manual.........................................10
4.2 Personnel training.....................................................................................................10
5Transport and storage ................................................................................. 10
5.1 Testing upon acceptance..........................................................................................10
5.2 Packaging / return transport .....................................................................................10
6Unpacking, Setup and Commissioning ..................................................... 11
6.1 Installation Site, Location of Use...............................................................................11
6.2 Unpacking, Scope of delivery ...................................................................................11
6.3 Mains connection......................................................................................................12
6.4 Battery operation (optional).......................................................................................12
6.5 Initial Commissioning................................................................................................12
6.6 Adjustment................................................................................................................13
7Basic Operation ........................................................................................... 15
8Density determination ................................................................................. 17
8.1 Principle of Density Determination............................................................................17
8.1.1 Influencing magnitudes and error sources ............................................................................... 18
8.2 Density determination of solids.................................................................................19
8.2.1 Density determination while using the density kits KERN YDB-01 or YDB-02........................ 19
8.2.2 Density determination using the suspended weighing device.................................................. 24
8.2.3 Density determination of solid material with a density of less than 1 g/cm3............................. 27
8.3 Determining density of liquids...................................................................................29
8.3.1 Density determination while using the density kits KERN YDB-01 or YDB-02........................ 29
8.3.2 Density determination using the suspended weighing device.................................................. 31

EMB-V-BA-e-1210
3
9Preconditions for Precise Measurements ................................................. 34
9.1 Calculation of Results...............................................................................................34
9.2 Influence Factors for Measurement Errors................................................................34
9.2.1 Air bubbles................................................................................................................................ 34
9.2.2 Solid body sample .................................................................................................................... 34
9.2.3 Liquids ...................................................................................................................................... 35
9.2.4 Surface ..................................................................................................................................... 35
9.2.5 Sinker for density determination of liquids................................................................................ 35
9.3 General information..................................................................................................35
9.3.1 Density / Relative Density......................................................................................................... 35
9.3.2 Drift of Balance Display ............................................................................................................ 35
10 Density Table for Fluids .............................................................................. 36
11 Uncertainty of Measurement for Density Determination of Solids .......... 37
12 User Instructions ......................................................................................... 38
13 Menu ............................................................................................................. 39
13.1 Navigation in the menu.............................................................................................39
13.2 Menu overview..........................................................................................................40
13.3 Description of individual menu items.........................................................................41
13.4 Interface parameters ................................................................................................44
14 Data output RS 232 C .................................................................................. 45
15 Service, maintenance, disposal .................................................................. 47
15.1 Clean........................................................................................................................47
15.2 Service, maintenance ...............................................................................................47
15.3 Disposal....................................................................................................................47
16 Instant help ................................................................................................... 48

EMB-V-BA-e-1210
4
1 Technical data
KERN EMB 200-3V EMB 2000-2V
Readability (d) 0.001 g 0.01
Weighing range (max) 200 g 2000 g
Reproducibility 0.002 g 0.02
Linearity ± 0.003 g ± 0.03 g
Recommended adjustment
weight, not added (class) 200 g
(F1)
2000 g
(F1)
Stabilization time (typical) 2.5 sec
Warm-up time 2 h
Unit g
Operating temperature +5°C… +35°C
Humidity of air max. 80 % (not condensing)
Housing (B x D x H) mm 170 x 240 x 39
Weighing plate mm Ø 82 Ø 150
Battery operation (optional) 9V block
Operating time: 12 h
Mains adapter 100 mA / 9V
AUTO-OFF-function
(With battery operation)
3 min.
Underfloor weighing Standard hooks
Interface RS-232 standard

EMB-V-BA-e-1210
5
2 Appliance overview
KERN EMB 200-3V
KERN EMB 2000-2V
bottom side

Weighing pan 
RS 232

Display 5
Battery compartment
Keyboard 6
Underfloor weighing

EMB-V-BA-e-1210
6
2.1 KERN EMB 200-3V with installed density kit KERN YDB-01
Upper sample dish of the immersion basket
Weighing plate "density kit"
Beaker
Lower sample dish of the immersion basket
Platform

EMB-V-BA-e-1210
7
2.2 KERN EMB 2000-2V with installed density kit KERN YDB-02
Upper sample dish of the immersion basket
Beaker
Lower sample dish of the immersion basket
Platform
Weighing plate "density kit"

EMB-V-BA-e-1210
8
2.3 Keyboard overview
Key Function
•Turn on/off
•Calculate weighing data via interface
•Menu access (longer pressing of the button)
•Cancel process/input
•Density determination mode to switch over to weighing mode
•Numeric input / dialing digits to the right
•Taring / Setting to zero
•Confirm
•Save and exit menu
•Adjustment menu access (longer pressing of the button)
•Density determination access mode for solids
•Scroll backwards in menu
•Density determination access mode for liquids
•Scroll forward in menu
•Weighing in air
•Weighing in liquid
2.3.1 Numeric entry
Key Function
Dialing the digits to the right, each active site flashes.
Each time you press the button, the numerical value of the
flashing digit increases.
Confirm entry

EMB-V-BA-e-1210
9
3 Basic Information (General)
3.1 Proper use
The scale purchased by you is intended to determine the density of solids and
liquids. The determination of the density is based on the Archimedean Principle, see
chapter 8.1.
Furthermore, the scale can also be used to determine the weighing value of the
weighing object. 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
pan. As soon as a stable weighing value is reached the weighing value can be read.
3.2 Improper Use
•Do not use balance for dynamic add-on weighing procedures, if small amounts of
goods to be weighed are removed or added. The “stability compensation“
installed in the balance may result in displaying an incorrect measuring value!
(Example: Slowly draining fluids from a container on the balance.)
•Do not leave permanent load on the weighing pan. This may damage the
measuring system.
•Impacts and overloading exceeding the stated maximum load (max) of the
balance, minus a possibly existing tare load, must be strictly avoided. Balance
may be damage by this.
•Never operate balance in explosive environment. The serial version is not
explosion protected.
•The structure of the balance may not be modified. This may lead to incorrect
weighing results, safety-related faults and destruction of the balance.
•The balance may only be used according to the described conditions. Other
areas of use must be released by KERN in writing.
3.3 Warranty
Warranty claims shall be voided in case
•Our conditions in the operation manual are ignored
•The appliance is used outside the described uses
•The appliance is modified or opened
•Mechanical damage or damage by media, liquids, natural wear and tear
•The appliance is improperly set up or incorrectly electrically connected
•The measuring system is overloaded

EMB-V-BA-e-1210
10
3.4 Monitoring of Test Resources
In the framework of quality assurance the measuring-related properties of the
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 national standard) fast and at moderate cost.
4 Basic Safety Precautions
4.1 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.
4.2 Personnel training
The appliance may only be operated and maintained by trained personnel.
5 Transport and storage
5.1 Testing upon acceptance
When receiving the appliance, please check packaging immediately, and the
appliance itself when unpacking for possible visible damage.
5.2 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.
Reattach possibly supplied transport securing devices.
Secure all parts such as the weighing platform, power unit
etc. against shifting and damage.

EMB-V-BA-e-1210
11
6 Unpacking, Setup and Commissioning
6.1 Installation Site, Location of Use
The balance is designed in a way that reliable weighing results are achieved in
common conditions of use.
You will work accurately and fast, if you select the right location for your balance.
On the installation site observe the following:
•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.
Non-permitted condensation (condensation of air humidity on the appliance)
may occur if a cold appliance is taken to a considerably warmer environment.
In this case, acclimatize the disconnected appliance for ca. 2 hours at room
temperature.
•Avoid static charge of goods to be weighed or weighing container.
•Do not operate in areas with hazard of explosive material or in potentially
explosive atmospheres due to materials such as gasses, steams, mists or
dusts.
•Keep away chemicals (such as liquids or gasses), which could attack and
damage the balance inside or from outside.
•If electro-magnetic fields or static charge occur, or if the power supply is
unstable major deviations on the display (incorrect weighing results) are
possible. In that case, the location must be changed.
6.2 Unpacking, Scope of delivery
Remove balance and accessories carefully from packaging, remove packaging
material and place device at the planned work place. Verify that there has been no
damage and that all packing items are present.
Scope of delivery / serial accessories:
•Balance, see chap. 2.0
•Mains adapter
•Flush-mounted hook
•Operating instructions

EMB-V-BA-e-1210
12
6.3 Mains connection
Power is supplied via the external mains adapter. The stated voltage value must be
the same as the local voltage.
Only use original KERN mains adapters. Using other makes requires consent by
KERN.
6.4 Battery operation (optional)
Remove the battery compartment cover on the underside of the scale and connect a
9 V block battery. Replace the battery compartment cover.
For battery operation the balance has an automatic switch-off function which can be
activated or deactivated in the menu (chapter 13).
In the weighing mode, press and hold longer until [Pr] is displayed.
Press repeatedly until "AF" appears.
Acknowledge with .
Use now to select between the following two settings:
„AF on“:
In order to save the battery, the balance switches automatically
off after 3 minutes without weighing.
„AF off“:
Switch-off function deactivated.
Acknowledge selection by . The balance returns to weighing mode.
If the batteries are run down, "LO" appears in the display. Press ON/OFF-key and
replace the batteries immediately.
If the balance is not used for a longer time, take out the batteries and store them
separately. Leaking battery liquid could damage the balance.
6.5 Initial Commissioning
A warming up time of 2 hours after switching on stabilizes the measuring values.
The accuracy of the balance depends on the local acceleration of gravity.
Strictly observe hints in chapter “Adjustment”.

EMB-V-BA-e-1210
13
6.6 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 for the first commissioning, after each
change of location as well as in case of fluctuating environment temperature. To
receive accurate measuring values it is also recommended to adjust the balance
periodically in weighing operation.
+ Prepare the required adjustment weight.
The adjustment should be made with the recommended adjustment weight
(see chap. 1 "Technical data"). Adjustment is also possible with the weights
of other nominal values (see table 13.3), but not the optimum for measuring
technique.
+ Observe stable environmental conditions.
+ A warming up time (see chapter 1) is required for stabilization.
+ Ensure that there are no objects on the weighing pan.
Procedure:
EMB 200-3V as an example.
1. Start balance by pressing .
2. Press and hold down longer, the display shows "CAL" briefly. Then the
display shows the exact size of the adjustment weight (See chapter 13.3).

3. During this display, set the adjustment weight in the middle of the weighing
plate

EMB-V-BA-e-1210
14
4. Press , short time later there appears „CAL F“, then the automatic return
to the weighing mode. In the display there appears the value of the adjustment
weight.

An error during adjustment or the use of an incorrect adjusting weight will result
in an error message „CAL E“. Repeat adjustment.
Keep the adjustment close to the balance. Daily control of the weighing
exactness is recommended for quality-relevant applications.

EMB-V-BA-e-1210
15
7 Basic Operation
EMB 200-3V as an example.
Start-up
Press the ON/OFF key.
The balance will carry out a self-test As soon as the
weight display appears, the balance is ready for
weighing.
Switching Off
Press ON/OFF button, the display disappears
Weighing Place goods to be weighed on balance.
Wait for stability display [g]
Read weighing result.
If the weighing object is heavier than the weighing range, the
display shows the error message "E".

EMB-V-BA-e-1210
16
Taring
Place an empty weighing container, the weight of the
weighing container will be displayed.
Press the TARE button, the zero display disappears. The
tare weight is saved until it is deleted.
Weigh the material, the net weight will be indicated.
The taring process can be repeated any number of times,
e.g. when adding several components for a mixture
(adding). The limit is reached when the whole weighing
range is exhausted.
After removing the weighing container, the weight of the
weighing container appears as negative display.
The tare weight is saved until it is deleted.
Delete tare
Unload the balance and press the TARE button, the zero
display appears.

EMB-V-BA-e-1210
17
ρ =
A
A-B
o
ρ
ρ =
m
V
8 Density determination
8.1 Principle of Density Determination
Three physical magnitudes are the volume and the mass of bodies as well as the
density of matter. In density mass and volume are related.
Density [ ρ ] is the relation of mass [ m ] to volume [ V ].
SI-unit of density is kilogram divided by cubic meter (kg/m³). 1 kg/m³ equals the
density of a homogenous body that, for a mass of 1 kg, has the volume of 1 m³.
Additional frequently applied units include:
1g
cm3
,
1kg
m
3
,
1g
l
The determination of the density is based on the "Archimedean Principle", which
states that every object that is dipped into a liquid is as much lighter as the liquid that
it displaces.
Thus, density is calculated according to the formulae below:
Density determination of solids
Our balances enable weighing of solids in air [ A ] as well as water [ B ]. If the density
of the buoyancy medium is known [ ρo ] the density of the solid [ ρ] is calculated as
follows:
ρ= density of sample
A = weight of the sample in air
B = weight of the sample in the aid liquid
ρo = density of the aid liquid

EMB-V-BA-e-1210
18
ρ =
V
A-B
Determining density of liquids
The density of a fluid is determined with the help of a sinker providing a known
volume [ V ]. The sinker is weighed in air [ A ] as well as in the test fluid [ B ].
According to the Archimedes’ Principle a body immersed in a fluid experiences a
force of buoyancy. [ G ]. This force equals the weight force of the fluid displaced by
the volume of the body.
The volume [ V ] of the immersed body equals the volume of the displaced fluid.
G = buoyancy of sinker
Buoyancy of sinker =
Weight of the sinker in air [ A ] -weight sinker in test liquid [ B ]
From this follows:
ρ= density of test liquid
A = weight of sinker in air
B = weight of the sinkers in test liquid
V = volume of sinker*
8.1.1 Influencing magnitudes and error sources
Air pressure
Temperature
Volume deviation of the sinker
Surface tension of the liquid
Air bubbles
Immersion depth of the sample dish of sinker
Porosity of the solid

EMB-V-BA-e-1210
19
8.2 Density determination of solids
For the determination of the density of solids, the solid is first weighed in air and then
in the aid liquid, whose density is known. From the weight difference results the
buoyancy from where the software calculates the density.
As aid liquid, usually distilled water or ethanol is used, see density table chapter 10.
8.2.1 Density determination while using the density kits KERN YDB-01
or YDB-02
For the density determination, we recommend to work with the optional density kit
KERN YDB-01 or YDB-02. This contains all the necessary structures and resources
for a comfortable and precise determination of the density.
•If needed, perform necessary adjustment prior to the installation of the
density kit, see chapter 6.6.
•When the density kit is installed, correct adjustment is not possible.
•For reasons of adjustment, take away the density kit and place the standard
weighing plate.
Fig.: Installed density kit KERN YDB-01

EMB-V-BA-e-1210
20
Abb.: Installed density kit KERN YDB-02