KERN&SOHN PWS User manual

KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: [email protected]
Phone: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Operating instructions
Precision balance
KERN PWS
Version 1.0
2022-08
GB
TPWS-BA-e-2210

1 TPWS-BA-e-2210
GB
KERN PWS
Version 1.0 2022-08
Operating instructions
Precision balance
Contents
1Technical data................................................................................................ 4
2Declaration of conformity ............................................................................. 5
3Appliance overview ....................................................................................... 6
3.1 Components.............................................................................................................................. 6
3.2 Keyboard ................................................................................................................................... 8
3.3 Display ....................................................................................................................................... 9
4Basic Information (General)........................................................................ 10
4.1 Proper use............................................................................................................................... 10
4.2 Improper Use .......................................................................................................................... 10
4.3 Warranty .................................................................................................................................. 10
4.4 Monitoring of Test Resources............................................................................................... 10
5Basic Safety Precautions ............................................................................ 11
5.1 Pay attention to the instructions in the Operation Manual ................................................ 11
5.2 Personnel training .................................................................................................................. 11
6Transport and storage................................................................................. 11
6.1 Testing upon acceptance ...................................................................................................... 11
6.2 Packaging / return transport ................................................................................................. 11
7Unpacking, Installation and Commissioning............................................. 12
7.1 Installation Site, Location of Use .......................................................................................... 12
7.2 Unpacking, Scope of delivery ............................................................................................... 12
7.3 Placing ..................................................................................................................................... 14
7.4 Levelling .................................................................................................................................. 15
7.5 Mains connection ................................................................................................................... 15
7.5.1 Turning On the Power .............................................................................................................. 16
7.6 Initial Commissioning ............................................................................................................ 16
7.7 Connection of peripheral devices......................................................................................... 16
8Menu ............................................................................................................. 17
8.1 Menu overview........................................................................................................................ 17
8.2 Navigation in the menu .......................................................................................................... 18
9Basic Operation ........................................................................................... 19
9.1 Turn on/off............................................................................................................................... 19
9.2 Zeroing .................................................................................................................................... 20
9.3 Taring....................................................................................................................................... 20
9.4 Selection of a weighing application ..................................................................................... 21
9.5 Simple weighing ..................................................................................................................... 22
9.6 Numeric entry ......................................................................................................................... 22
10 Piece counting ............................................................................................. 24
11 Percent weighing ......................................................................................... 27
12 Coefficient multiplication ............................................................................ 30
13 Density determination ................................................................................. 32
13.1 Density Table for Liquids ...................................................................................................... 36
13.2 Data output of the specific density to a printer................................................................... 37

TPWS-BA-e-2210 2
14 Animal weighing .......................................................................................... 38
14.1 Additional settings ................................................................................................................. 38
14.1.1 Auto Tare.............................................................................................................................. 39
14.1.2 Data output........................................................................................................................... 39
14.1.3 Set weight range .................................................................................................................. 39
14.1.4 Set the balance's response. ................................................................................................. 39
15 Weighing with tolerance range................................................................... 40
15.1 Selection of weighing function with tolerance range ......................................................... 41
15.2 Set discrimination condition ................................................................................................. 41
15.3 Setting the discrimination range .......................................................................................... 41
15.4 Set the number of tolerance limits ....................................................................................... 41
15.5 Set discrimination method .................................................................................................... 42
15.6 Set acoustic signal ................................................................................................................. 42
15.7 Setting the tolerance values.................................................................................................. 42
15.7.1 Absolute values .................................................................................................................... 42
15.7.2 Differential values................................................................................................................. 45
15.8 Setting the display to present results .................................................................................. 49
16 Totalization................................................................................................... 50
16.1 Select the Totalizing function ............................................................................................... 50
16.2 Using the totalizing function ................................................................................................. 51
16.2.1 TOTAL-Adding ..................................................................................................................... 51
16.2.2 NET-Adding.......................................................................................................................... 51
16.3 Show or clear the total sum .................................................................................................. 52
17 Settings for operation and operating behaviour....................................... 53
17.1 Setting the weighing units..................................................................................................... 53
17.2 Bar graph display ................................................................................................................... 54
17.3 Acoustic signal ....................................................................................................................... 54
17.3.1 Activate / deactivate the acoustic signal .............................................................................. 54
17.3.2 Adjusting the sound level of the acoustic signal .................................................................. 54
17.4 Background lighting............................................................................................................... 54
17.4.1 Turn off of the background lighting automatically ................................................................ 55
17.4.2 Checking the background lighting ........................................................................................ 55
17.5 Stability settings..................................................................................................................... 55
17.5.1 Sensitivity ............................................................................................................................. 55
17.5.2 Stabilisation waiting time...................................................................................................... 55
17.6 Reaction settings.................................................................................................................... 56
17.7 Zero-Tracking.......................................................................................................................... 56
17.8 Automatic switch-on function............................................................................................... 56
18 System Settings ........................................................................................... 57
18.1 Balance identification number .............................................................................................. 57
18.2 Readability .............................................................................................................................. 58
18.2.1 Readabilities for PWS 800-2 ................................................................................................ 59
18.2.2 Readabilities for PWS 3000-1 and PWS 8000-1 ................................................................. 59
18.3 Restore last tare value ........................................................................................................... 60
18.4 Restore factory settings ........................................................................................................ 60
19 Adjustment ................................................................................................... 61
19.1 Adjustment.............................................................................................................................. 61
19.2 Adjustment test ...................................................................................................................... 62
20 Interfaces...................................................................................................... 64
20.1 RS-232C interface for data input and output ....................................................................... 64
20.1.1 Technical data ...................................................................................................................... 64
20.1.2 Interface cable...................................................................................................................... 65
20.2 Data output formats ............................................................................................................... 65
20.2.1 Data composition ................................................................................................................. 65
20.2.2 Data description ................................................................................................................... 65
20.3 Data input ................................................................................................................................ 67
20.3.1 Input format .......................................................................................................................... 67
20.4 Response formats .................................................................................................................. 69

3 TPWS-BA-e-2210
20.4.1 A00/Exx Format ................................................................................................................... 69
20.4.2 ACK/NAK Format ................................................................................................................. 70
20.5 Communication settings........................................................................................................ 70
20.5.1 Enable / disable interface and data format .......................................................................... 70
20.5.2 Change communication settings .......................................................................................... 70
20.6 Printer functions..................................................................................................................... 72
20.6.1 Output of the adjustment test result ..................................................................................... 73
20.6.2 Output of measurements obtained....................................................................................... 73
20.6.3 Output language................................................................................................................... 73
21 Servicing, maintenance, disposal .............................................................. 74
21.1 Cleaning .................................................................................................................................. 74
21.2 Servicing, maintenance ......................................................................................................... 74
21.3 Disposal................................................................................................................................... 74
22 Instant help for troubleshooting................................................................. 75
22.1 Error messages ...................................................................................................................... 76

TPWS-BA-e-2210 4
1 Technical data
KERN
PWS 3000-1
PWS 8000-1
PWS 800-2
Item no./ Type
TPWS 3200-1-A
TPWS 8200-1-A
TPWS 820-2-A
Readability (d)
0.1 g
0.1 g
0.01 g
Weighing range
(max)
3.2 kg
8.2 kg
820 g
Reproducibility
0.1 g
0.1 g
0.01 g
Linearity
0.1 g
0.1 g
0.01 g
Stabilization time
3 s
Recommended
adjustment weight,
not added (Category)
3 kg (F1)
2 kg (F1);
5 kg (F1)
200 g (F1);
500 g (F1)
Warm-up time
2 h
Weighing Units
g, kg, ct, oz, lb, ozt, dwt, gn, tl (Hong Kong), tl (Singapore,
Malaysia), tl (Taiwan), mom, to
Smallest part weight
during piece counting
100 mg (under lab
conditions*)
100 mg (under lab
conditions*)
10 mg (under lab
conditions*)
1 g (under normal
conditions**)
1 g (under normal
conditions**)
100 mg (under
normal
conditions**)
Reference piece
quantities at piece
count
5, 10, 30, 100
Weighing plate,
stainless steel
190 x 190 mm
190 x 190 mm
ø 140 mm
Dimensions of the
housing (B x D x H)
[mm]
310 x 208 x 87
Net weight (kg)
1.52 kg
Permissible
ambient condition
10 °C to + 30 °C
Humidity of air
80 %
Power supply unit
input voltage
AC 100-240 V, 300 mA 50/60Hz
Balance input voltage
DC 5.95 V,
1.0 A
Interfaces
RS-232
Degree of pollution
2
Overvoltage category
2
Metres in height
Up to 2000 m
Place of installation
In sealed rooms only

5 TPWS-BA-e-2210
* Smallest component weight for part counting - under lab conditions:
➢There are ideal ambient conditions for high-resolution counting
➢The parts to be counted are not scattered
** Smallest component part for part counting –under normal conditions:
➢There are unsteady ambient conditions (draft, vibrations)
➢The parts to be counted are being scattered
2 Declaration of conformity
The current EC/EU Conformity declaration can be found online in:
www.kern-sohn.com/ce
For verified weighing scales (= weighing scales assessed for
conformity) the declaration of conformity is included in the scope of
delivery.

TPWS-BA-e-2210 6
3 Appliance overview
3.1 Components
PWS 3000-1 and PWS 8000-1:
PWS 800-2:
Pos.
Designation
1
Weighing plate
2
Keyboard
3
Footscrews
4
Display
5
Bubble level
1
1
2
4
3
5

7 TPWS-BA-e-2210
Rear view (weighing plate on the picture: PWS 3000-1 and PWS 8000-1):
Pos.
Designation
6
Attachment eyelet for anti-theft device
7
Power plug with protective cap
8
RS-232C interface with protective cap
9
Battery compartment (rechargeable
battery is available as an optional
accessory)
View from below:
Pos.
Designation
10
Cover hook for underfloor weighing
7
9
8
6
10

TPWS-BA-e-2210 8
3.2 Keyboard
Button
Designation
Description
[ON/OFF]
Switch-on
Switching Off
[PRINT]
Data export to external device
Cancel setting
[SET]
Accept setting
[F]
Open menu (keep key pressed for about 2 seconds)
Change display
Confirm entry
[TARE/ZERO]
Taring and zeroing
[]
Setting selection upwards
Increase numerical input by 1
[]
Select setting downwards
Lower numerical input by 1
[]
Forward to next menu level
Select character position
[]
Menu level back
Select character position

9 TPWS-BA-e-2210
3.3 Display
No.
Display
Designation
Description
1
Stability display
Is displayed when the weight
value is stable
2

"Tolerance range weighing"
indicator
Indicates the tolerance range
within which the weighing result
lies.
3

"Animal weighing" indicator
Indicates the reaction speed of
the balance when weighing
animals.
4
Asterisk
Indicates that weight value can be
added
5
Minus
Displays negative values
6
M
Indicator "Process"
Indicates that the balance is
processing data
7
Indicator “zero display”
Displays zero position
8
Bar graph display
Indicates how much the weighing
plate is loaded with respect to the
maximum weighing range
Indicates the tolerance range of
the weighing result
9
Charge status display
Displayed during battery
operation
10
Display gross weight value
Displays gross weight
11
Indicator „Data output"
Displayed when balance is
sending data to external device
12
"Animal weighing" indicator
Shown when the balance is in
animal weighing mode
13
Display net weight value
Shown when the tare weight has
been subtracted
14
Σ
"Total" indicator
Shown when the total sum is
displayed
15
PCS
“Piece counting” indicator
Shown when piece counting has
been activated
16
#
"Coefficient multiplication"
indicator
Shown when coefficient
multiplication has been activated.
17
%
„Percent Weighing“ Indicator
This is displayed when the
percent weighing function has
been activated.
18
(top) and 
"ID number" indicator
Lights up when ID is displayed or
entered.
19
g
Gram
Shows unit „Gram“
20
kg
Kilogram
Shows unit „Kilogram“
21
(mom)
Momme
Indicates "Momme" unit
22
Indicator for different weighing
units
Indicates different weighing units
in different functions

TPWS-BA-e-2210 10
4 Basic Information (General)
4.1 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 balance”, i.e. the
material to be weighed is manually and carefully placed in the center of the weighing
pan. The weighing result can be read off once a stable weight value has been
reached.
4.2 Improper Use
•Our balances are non-automatic balances and not provided for use in dynamic
weighing processes. However, the balances can also be used for dynamic
weighing processes after verifying their individual operative range, and here
especially the accuracy requirements of the application.
•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 the 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.
4.3 Warranty
The warranty becomes void if:
•Our conditions in the operation manual are ignored
•The appliance is used beyond 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
4.4 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 regarding the test equipment monitoring of balances as well as the test
weights required for this is available on the KERN homepage (www.kern-sohn.com).
In KERN's accredited DKD calibration laboratory test weights and balances may be
calibrated (return to the national standard) fast and at moderate cost.

11 TPWS-BA-e-2210
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.
5.2 Personnel training
The appliance may only be operated and maintained by trained staff.
6 Transport 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.
Reattach possibly supplied transport securing devices.
Secure all parts such as the glass wind screen, the weighing
plate, power unit etc. against shifting and damage.

TPWS-BA-e-2210 12
7 Unpacking, Installation and Commissioning
7.1 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.
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.
•Keep IP protection of the device.
•If any electromagnetic fields occur, static charges (for example when weighing
/ counting plastic parts) as well as unstable power supply, large display
deviations (incorrect weighing results, as well as damage to the balance) are
possible. In that case, the location must be changed.
7.2 Unpacking, Scope of delivery
Remove device and accessories from packaging, remove packaging material and
install the device at the planned work place. Check if that there has been no damage
and that all items of delivery scope are present.

13 TPWS-BA-e-2210
Scope of delivery:
1. Balance
2. Weighing plate (for
PWS 3000-1 and
PWS 8000-1)
3. Weighing plate (for
PWS 800-2)
4. Weighing plate
support (for PWS
3000-1 and PWS
8000-1)
5. Weighing plate
support (for PWS
800-2)
6. Screw for weighing
plate support
7. Mains adapter
8. Power plug set
9. Operating
instructions

TPWS-BA-e-2210 14
7.3 Placing
The correct location of high-resolution precision balances is crucial for the
accuracy of the weighing results (see chapter 7.1).
The IP protection of the balance is only maintained if
•the weighing plate is attached
•the hole on the underside is covered with the appropriate cover
1. Place the weighing plate carrier with the holes over the pins on the balance.
2. Fix the weighing plate with the screw
2. Place the weighing plate on the weighing plate carrier
PWS 3000-1 and PWS 8000-1:
PWS 800-2:
3. Connect the power supply unit (Installation of the power supply unit: see
chap.7.5)
Pins

15 TPWS-BA-e-2210
7.4 Levelling
1. Level balance with foot screws until the air bubble of the water balance is in
the prescribed circle
Check levelling regularly
7.5 Mains connection
Select a country-specific power plug and insert it in the mains adapter.
Check, whether the voltage acceptance on the balance is set correctly.
Do not connect the balance to the power mains unless the information
on the balance (sticker) matches the local mains voltage.
Only use KERN original mains adapter. Using other makes requires
consent by KERN.
Important:
➢Before starting your weighing balance, check the mains cable for
damage.
➢Make sure that the power supply unit and the power plug do not
come into contact with liquids. Cover the power connector with the
protective cap provided whenever the balance is disconnected from
the electricity supply.
➢Ensure access to mains plug at all times.
Installation of the power supply unit:
1. Place the country-specific power plug at a slight angle in the recess of
the power supply unit so that the spring points in the direction of the
locking arrow of the power supply unit.
2. Push the locking mechanism of the power plug downwards and press
the power plug into the recess of the power supply unit. Then release
the lock (make sure that the power plug is engaged).
Footscrews
Bubble level

TPWS-BA-e-2210 16
Side view of the power plug (simplified):
Inserting the power plug into the power supply unit
7.5.1 Turning On the Power
Connect the balance to the power supply
Turn on the balance by pressing the [ON/OFF] key.
7.6 Initial Commissioning
The balances must have reached their operating temperature for accurate weighing
results to be obtained from the electronic balances (see Warm-up Time, Chapter 1).
During this warming up time the balance must be connected to the power supply
(mains, accumulator or battery). The accuracy of the balance depends on the local
acceleration of gravity. It is essential that the instructions in the chapter on
Adjustment are followed (see chap.19).
7.7 Connection of peripheral devices
Before connecting or disconnecting of additional devices (printer, PC) to the data
interface, always disconnect the balance from the power supply.
Make sure that the connections of the RS-232C interface and the connection for
peripheral devices do not come into contact with liquids. Cover the connectors on the
machine with the protective caps provided when not in use.
With your balance, only use accessories and peripheral devices by KERN, as they
are ideally tuned to your balance.
1.
2.
Groove
Spring
Locking arrow
Lock

17 TPWS-BA-e-2210
8 Menu
Settings on the balance can be changed from the menu by pressing the [F] key.
•To open the menu, the balance must be in the gram display (switch-
over the display: Press [F] key).
•For navigation in the menu see chapter 8.2
8.1 Menu overview
The balance's menu consists of several levels. The first level consists of the main
menus. Depending on the setting, you get access to further menu levels.
You will find a summary of the setting options in the individual chapters.
First menu level
Settings
Chapter
Selection of a weighing
application
9.4
Weighing with tolerance range
15
Totalization
16
Zero-Tracking
17.7
Stability settings: Sensitivity
17.5.1
Reaction settings
17.6
Communication settings
20.5
Adjustment functions
19
Bar graph display
0
Automatic switch-on function
17.8
Turn off of the backlight
automatically
17.4.1
Weighing unity A
17.1
Readability unit A
18.2
Weighing unit B
17.1
Readability unit B
18.2
Printer functions
20.6
Stabilisation waiting time
17.5.2
Restore last tare value
18.3
Acoustic signal settings
17.3
Checking the backlight
17.4.2

TPWS-BA-e-2210 18
8.2 Navigation in the menu
Button
Designation
Description
[F]
Open menu (press and hold for about 2 seconds)
Following menu level (press briefly)
[PRINT]
Close menu
Cancel input
[]
Forward to next menu level
[]
Menu level back
[]
Setting selection upwards
[]
Select setting downwards
[TARE/ZERO]
Switch through setting selection
[SET]
Storing settings
Open menu:
Press and hold the [F] key for about 2 seconds.
Display changes to <Func>.
Release [F] key
If you continue to hold down the [F] key after <Func> is displayed, the
balance will switch to another mode. In this situation you can press the
[PRINT] key to cancel the action.

19 TPWS-BA-e-2210
9 Basic Operation
9.1 Turn on/off
Start-up:
Press [ON/OFF] key
The display lights up
Wait until the weight display appears
The display shows zero
The balance is now ready for weighing
Check the display:
You can check whether the weight value shown on
the display changes using light finger pressure on
the weighing plate,
Switching off:
When the balance is switched on, press the
[ON/OFF] key.
The balance display turns off
After switching on, the balance always starts with the last weighing
application that was used before switching off.