KERN WTB-N User manual

KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: [email protected]
Tel: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Operating instructions
Compact balance
KERN WTB-N
Version 2.0
09/2012
GB
WTB-N-BA-e-1220

WTB-N-BA-e-1220 2
GB
KERN WTB-N
Version 2.0 09/2012
Operating instructions
Compact balance
Contents
1Technical data ............................................................................................ 3
1.1 Dimensions............................................................................................................................. 5
2Appliance overview.................................................................................... 6
2.1 Overview of display................................................................................................................ 6
2.2 Keyboard overview................................................................................................................. 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................................................................................................ 9
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 and placing......................................................................................................... 12
6.2.1 Scope of delivery.................................................................................................................. 14
6.3 Rechargeable battery operation (optional)........................................................................... 14
6.3.1 Mains connection during rechargeable battery operation.................................................... 16
6.4 Initial Commissioning........................................................................................................... 17
6.5 Type of protection IP65........................................................................................................ 17
7Adjustment ............................................................................................... 17
7.1 Adjustment ........................................................................................................................... 17
7.1.1 Adjustment ........................................................................................................................... 18
8Operation .................................................................................................. 19
8.1 Weighing .............................................................................................................................. 19
8.2 Taring................................................................................................................................... 19
8.3 Background illumination....................................................................................................... 20
8.4 Weighing with tolerance range............................................................................................. 21
9The menu .................................................................................................. 23
9.1 Navigation in the menu ........................................................................................................ 23
9.2 Menu overview..................................................................................................................... 24
9.3 Set auto-OFF function.......................................................................................................... 25
9.4 Multi-Tare function ............................................................................................................... 26
10 Error messages........................................................................................ 26
11 Instant help............................................................................................... 27
12 Service, maintenance, disposal.............................................................. 28
12.1 Cleaning............................................................................................................................... 28
12.2 Service, maintenance........................................................................................................... 28
12.3 Disposal................................................................................................................................ 28

3 WTB-N-BA-e-1220
1 Technical data
KERN
WTB
1K -4N
WTB
3K -3N
WTB
6K -3N
Weighing range (max)
1.5 kg
3 kg
6 kg
Readability (d)
0.2 g
0.5 g
1 g
Reproducibility
0.2 g
0.5 g
1 g
Linearity
±0.4 g
±1 g
±2 g
Recommended adjustment
weight, not added (class)
1500 g
(M1)
3 kg
(M1)
6 kg
(M1)
Stabilization time (typical)
2 sec.
Units
kg
Warm-up time
30 min.
Electric Supply
Input voltage: 110V-230V AC
Power supply unit: 12 V, 500 mA
Rechargeable battery
operation
Service life: background illumination ON: 30 h
Background illumination off: 50 hours
Loading time 12 h
Auto-Off (rechargeable
battery)
15 min., 5 min., 3 min., off
Display type
LCD with background illumination
Character height 2.5 cm
Operating temperature
-10° C …. + 40° C
Humidity of air
0 % - 80 % (non-condensing)
Dimensions of weighing plate
(Stainless steel) (mm)
262 x 202
Casing dimensions
286 x 316 x 126.5
Weight kg (net)
3.2
IP protection
IP65

WTB-N-BA-e-1220 4
KERN
WTB
10K -3N
WTB
30K -3N
Weighing range (max)
15 kg
30 kg
Readability (d)
2 g
5 g
Reproducibility
2 g
5 g
Linearity
±4 g
±10 g
Recommended adjustment
weight, not added (class)
15 kg
(M1)
30 kg
(M1)
Stabilization time (typical)
2 sec.
Units
kg
Warm-up time
30 min.
Electric Supply
Input voltage: 110V-230V AC
Power supply unit: 12 V, 500 mA
Rechargeable battery
operation
Service life: background illumination ON: 30 h
Background illumination off: 50 hours
Loading time: 12 h
Auto-Off (rechargeable
battery)
15 min., 5 min., 3 min., off
Display type
LCD, digit height 25 mm
Operating temperature
-10° C …. + 40° C
Humidity of air
0 % - 80 % (non-condensing)
Dimensions of weighing plate
(Stainless steel) (mm)
262 x 202
Casing dimensions
286 x 316 x 126.5
Weight kg (net)
3.2
IP protection
IP65

5 WTB-N-BA-e-1220
1.1 Dimensions

WTB-N-BA-e-1220 6
2 Appliance overview
1Weighing plate
2Keyboard
3Bubble level
4Display
2.1 Overview of display
Rear view:

7 WTB-N-BA-e-1220
Display
Description
Description
Zeroing display
Should the balance not display exactly zero
despite empty scale pan, press the
button. The balance will be set to zero after a
short standby time.
Stability display
Scales are in a steady state
Net weight display
Net weight will be displayed
Capacity display
Rechargeable battery
Triangle above the capacity indicator appears
when the battery capacity is almost exhausted
Display Weighing with
tolerance range
Triangle above "+": upper limit value
Triangle above "-": lower limit value
Power supply connected
Lights with power supply via power supply unit,
then the battery is being charged
Display Weighing unit kg
Displayed weight in kg

WTB-N-BA-e-1220 8
2.2 Keyboard overview
Key
Description
Function
in menu
ON/OFF-switch
Turn on/off
TARE button
Tare balance
Weighing with
tolerance range
Call up menu
Change to the next menu
item /parameter
Zero setting key
Set balance to zero
Select menu item /
parameter
+
Push TARE + reset
button
simultaneously
Switch-over units

9 WTB-N-BA-e-1220
3 Basic Information (General)
3.1 Proper use
The balance you purchased is intended to determine the weighing value of material
to be weighed. It is intended to be used as a “non-automatic balcance”, 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 weighings. 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“. (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
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.

WTB-N-BA-e-1220 10
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.
All language versions contain a non-binding translation. The original
German is binding.
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 glass wind screen, the weighing
platform, power unit etc. against shifting and damage.

11 WTB-N-BA-e-1220
6 Unpacking, Setup and Commissioning
6.1 Installation Site, Location of Use
The balances are 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.
Therefore, observe the following for the installation site:
Place scales on a stable, even 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.
Major display deviations (incorrect weighing results) may be experienced should
electromagnetic fields (e.g. due to mobile phones or radio equipment), static
electricity accumulations or instable power supply occur. Change location or remove
source of interference.

WTB-N-BA-e-1220 12
6.2 Unpacking and placing
Carefully remove the balance from the packaging, remove plastic cover and setup
balance at the intended workstation.
1
Weighing pan
2
Locking screw
3
Carrier weighing plate
4
Shim
5
Display
6
Bubble level
7
Keyboard
8
Footscrews
9
Rechargeable battery compartment cover
10
Screws of battery compartment cover

13 WTB-N-BA-e-1220
Level balance with foot screws until the air bubble of the water balance is in the
prescribed circle.
1Rechargeable battery
compartment
2Mains port
3Pressure compensation screw
Pressure compensation screw:
[1]
On the lower side of the balance there is a pressure compensation screw [1] which
has to be opened for the weighing process. Fasten the screw before cleaning the
balance.

WTB-N-BA-e-1220 14
6.2.1 Scope of delivery
Serial accessories:
Balance
Weighing pan
Carrier weighing plate
Fastening screw of the carrier weighing plate
Operating instructions
Hexagonal socket wrench
6.3 Rechargeable battery operation (optional)
The rechargeable battery is charged via the delivered power supply.
The operating time of the rechargeable battery with background illumination is 30h,
without that it is 50 hrs. Charging time until complete recharging 12h.
In the menu you can activate the AUTO-OFF function time off], see chap. 9.2.
According to menu settings, the balance switches automatically off in order to spare
the battery.
Insert rechargeable battery:
Remove any
adherent moisture
from the balance
Rotate both levers
(1) 90 degrees to the
left
Membrane for degree of
protection IP65

15 WTB-N-BA-e-1220
Remove battery compartment
cover and the foam pieces
Connecting the rechargeable
battery
Watch the colours:
Red on red !
Black on black!
Insert the rechargeable battery
in a manner that it cannot slip
(fasten with a rubber foam mat)
Ensure that the cables are
not squeezed.

WTB-N-BA-e-1220 16
Close the rechargeable battery
cover
Rotate both levers (1) 90 degrees to
the right
If in the display the triangle appears above the capacity display , the
rechargeable battery is nearly exhausted. Connect power pack, the rechargeable
battery is loaded.
Avoid excess pressure on the balance in order to avoid damaging
it, particularly as it is supported by the weighing plate.
6.3.1 Mains connection during rechargeable battery operation
During the rechargeable battery operation ensure that the mains
connection is covered with a rubber cap.
Only by this the type of protection IP65 is ensured.

17 WTB-N-BA-e-1220
6.4 Initial Commissioning
In order to obtain exact results with the electronic balances, your balance must have
reached the operating temperature (see warming up time chap. 1).
For this warm-up period the scale must be connected to the power supply (batteries).
The accuracy of the balance depends on the local acceleration of gravity.
Strictly observe hints in chapter Adjustment.
6.5 Type of protection IP65
The KERN WTB meets the requirements for IP65 protection type.
Suitable for a short-time contact with liquids. For cleaning use damp cloth. Dust-tight.
7 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.
7.1 Adjustment
Carry out adjustment as close as possible to the maximum load of the scales )see
chap. 1 „Technical data“). The accuracy of the adjustment weight must correspond
approximately to or, if possible, be better than, the readability d of the balance.
Information about test weights you will find in the internet under http://www.kern-
sohn.com
Procedure when adjusting:
Observe stable environmental conditions. A warming up time (see chapter 1) is
required for stabilization.

WTB-N-BA-e-1220 18
7.1.1 Adjustment
Display
Operation

Start balance by pressing
While the balance carries out a self test (00…- 99…), press
and keep pressed until „F1 CAL“ appears on the
display.
Press ;
in the display appears „UnLod“. Wait for the triangle above
the stability symbol, then press , the value of the last-
used adjustment weight is displayed. Exp: „6 kg“. If
necessary, change value by .
(example)
Place the adjustment weight
Wait for the triangle above the stability symbol
Press
While the balance carries out a self-test, take away the
adjustment weight
The balance changes over to zero display.
Now the process of adjustment is completed.
If the display shows an error message or an incorrect value, repeat adjustment
process. If the error message remains, please contact your dealer.

19 WTB-N-BA-e-1220
8 Operation
8.1 Weighing
Start balance by pressing .
The balance will carry out a self-test
When the weight display shows "0.0" and the triangle symbol
above the stability display appears, the scale is ready
for weighing.
However, you can reset the weighing scale to zero by pressing
the key.
Switch off balance using .
The "0.0" display disappears and the scales are switched off.
8.2 Taring
The tare weight of any preloads can be deducted by pressing a button so that the
actual weight of the weighed material is displayed in subsequent weighings.
(example)

Put on weighing receptacles and press .
The zero display appears, and above the reset symbol
the stability symbol and the net weight symbol the
triangle appears.
The weight of the container is now internally saved.
(example)
Place goods to be weighed in the weighing container.
The net weight of the goods to be weighed is displayed.
The weight of the weighing container will be displayed as a
minus number (=gross weight) after removing the weighing
container.

WTB-N-BA-e-1220 20
The tare weight is saved until it is deleted. Remove the load
from the balance and press . The zero display appears
and the triangle above the net weight symbol
vanishes.
Gross weight:
Press as long as the weighing container and the
object to be weighed are on the weighing plate.
Remove the object to be weighed as well as the weighing
container.
The gross weight is displayed as a negative value.
8.3 Background illumination

In weighing mode press for about 3 seconds, "bK-AU"
appears.
Press to select background illumination automatically
off („bK-AU“) and background illumination off („bK-oF“).
Press to confirm selected setting.
The balance changes into weighing mode