KERN RFS User manual

KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
email: [e-mail]
Tel: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Instruction Manual
Price computing scales
KERN RFS
Version 1.0
01/2011
GB
RFS-BA-e-1110

GB KERN RFS
Version 1.0 01/2011
Instruction Manual
Price computing scales
RFS-BA-e-1110
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Contents
1TECHNICAL DATA............................................................................................. 4
2APPLIANCE OVERVIEW ................................................................................... 5
2.1 Overview of display.................................................................................................................. 6
2.2 Keyboard overview................................................................................................................... 7
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
5TRANSPORTATION & STORAGE................................................................... 10
5.1 Testing upon acceptance ...................................................................................................... 10
5.2 Packaging................................................................................................................................ 10
6UNPACKING, SETUP AND COMMISSIONING ............................................... 10
6.1 Installation Site, Location of Use.......................................................................................... 10
6.2 Unpacking / Scope of delivery .............................................................................................. 11
6.3 Assembly post-mounted display .......................................................................................... 11
6.4 Mains connection ................................................................................................................... 12
6.5 Battery power supply............................................................................................................. 12
6.6 Initial Commissioning ............................................................................................................ 12
6.7 Adjustment.............................................................................................................................. 13
6.8 Verification .............................................................................................................................. 15
6.8.1 Position of seals and adjusting switch ................................................................................. 16
6.9 Checking the balance verification settings ......................................................................... 16
6.9.1 Service mode ....................................................................................................................... 17

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7BASIC OPERATION......................................................................................... 20
7.1 Switching on/off ..................................................................................................................... 20
7.2 Zeroing .................................................................................................................................... 20
7.3 Taring....................................................................................................................................... 20
7.4 Overload warning ................................................................................................................... 20
8WEIGHING WITH PRICE DETERMINATION ................................................... 21
8.1 Basic price entry via keyboard ............................................................................................. 21
8.2 Memory for basic price (PLU = Price look up)..................................................................... 22
8.2.1 Direct PLU 1∼PLU 28“.......................................................................................................... 22
8.2.2 Indirect PLU 1∼PLU 99“ ....................................................................................................... 24
8.3 Totalization.............................................................................................................................. 27
9ADDITIONAL USEFUL FUNCTIONS ............................................................... 30
9.1 AUTO CLEAR .......................................................................................................................... 30
9.2 Display background illumination.......................................................................................... 30
9.3 How to set date/time for sales receipt.................................................................................. 31
10 PRINTER „SALES RECEIPT“ ...................................................................... 32
10.1 Printout examples .................................................................................................................. 32
10.2 Change paper roll ................................................................................................................... 33
11 DATA OUTPUT RS 232C.............................................................................. 34
11.1 Technical data......................................................................................................................... 34
11.2 Pin allocation of the balance output socket (front view) ................................................... 34
12 SERVICE, MAINTENANCE, DISPOSAL, ERROR MESSAGES .................. 34
12.1 Cleaning .................................................................................................................................. 34
12.2 Service, maintenance............................................................................................................. 34
12.3 Disposal................................................................................................................................... 34
12.4 Error messages ...................................................................................................................... 34

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1 Technical data
KERN RFS 6K2HM RFS 15K5HM RFS 30K10HM
Weighing range (max) 6 kg 15 kg 30 kg
Readability (d) 2 g 5 g 10 g
Minimum load 40 g 100 g 200 g
Verification value 2 g 5 g 10 g
Verification class III III III
Reproducibility 2 g 5 g 10 g
Linearity ± 4 g ± 10 g ± 20 g
Stabilization time 3 s 3 s 3 s
Recommended adjusting
weight (not supplied) 6 kg (M2) 15 kg (M2) 30 kg (M1)
Warming up time
(operating temperature) 10 min
Net weight (kg) 7 kg
Dimensions of the housing
(B x D x H) 370 x 310 x 125
Weighing plate, stainless
steel 370 x 240 mm
Tripod height 47 cm
Weighing unit €/kg; €/100 g
Permissible ambient
condition -10° C to 40° C
Allowable air humidity 0 % - 85 % (non-condensing)
Electric Supply Line adapter 230 V AC, 50/60 Hz
Weighing balance 9 V DC, 800mA
6 V, 10 Ah
Operating period without printer – background lighting on 30 h
Operating period without printer – background lighting off 80 h
Rechargeable battery
Loading time approx. 12 hrs.
Data interface RS 232C

2 Appliance overview
1. PLU direct price keys
2. Bubble level
3. Post-mounted display
4. Battery compartment underneath weighing pan
5. Printer „Sales receipt“
6. Numeric keys
7. RS 232 interface
8. Levelling screw
9. ON/OFF switch
10. Mains adapter connection
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2.1 Overview of display
Weight Basic price
Sales price
Display weight:
Here, the weight of your goods is displayed.
The arrows above the symbols show:
aZeroing display
Stability display
NET Net weight
Display basic price:
Enter your basic price here either in €/kg or €/100 g using the keyboard, switching
between €/kg or €/100 g possible.
The arrows above the symbols show:
AUTO CLEAR Set basic price is deleted automatically
when balance is unloaded
€/kg Basic price in €/kg
€/100 g Basic price in €/100 g
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Display sale price:
Here the sales price is displayed in Euro [€].
The arrows above the symbols show:
+ Data in summation memory
TOTAL Total
Battery very low
2.2 Keyboard overview
1 2
1. Bubble level
Level balance with foot screws until the air bubble of the
water balance is in the prescribed circle.
2. Storage battery status display
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Selection Function
∼•Numeric keys, input basic price/PLU
•Display „End total“
•Delete key
∼
•PLU direct price keys for 28 frequently reoccurring item
prices, see chpt. 8.2.1
•Saving and retrieving item prices (indirect PLU), see
chpt. 8.2.2
•Addition in total memory
•Taring key
•Save settings
•Zeroing key
•Back to weighing mode
•Set basic price is deleted automatically when balance is
unloaded
•Switch-over key €/kg or €/100 g
•Issue to external device
•Line advance “sales receipt”
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3 Basic Information (General)
3.1 Proper use
The balance acquired by you serves to determine weight and price. 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. As soon as the goods to be
weighed are placed on the balance and the basic price has been set the price is
calculated automatically and displayed.
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“ in the balance. (Example: Slowly
draining fluids from a container on the balance.)
Do not leave permanent load on the weighing plate. 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.

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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 Transportation & 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
Keep all parts of the original packaging in case you need to return the appliance.
Only use original packaging for returning. Before sending, disconnect all connected
cables and loose/movable parts. Attach possibly existing transport safeguards.
Secure all parts, e.g. weighing plate, power unit etc., to prevent slipping and damage.
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.
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.
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
Carefully remove the balance from the packaging, remove plastic cover and setup
balance at the intended workstation.
Serial accessories:
•Balance, see chpt. 2
•Mains power supply
•Rechargeable battery
•Instruction Manual
6.3 Assembly post-mounted display
[1]
[2]
[3]
[4]
Plug tripod [1] of the post-mounted display into the provided support [2] of the
balance. Fix by using the two supplied screws [3] and [4]. Ensure that the interior
cable does not get damaged or trapped.
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6.4 Mains connection
Power is supplied via the external mains adapter. The stated voltage value must be
the same as the local voltage. Only use KERN original mains adapter. Using other
makes requires consent by KERN.
6.5 Battery power supply
The rechargeable battery is charged via the delivered power supply.
Before the first use, the battery should be charged by connecting it to the mains
power supply for at least 15 hours.
An arrow [T]appearing on the weight display above the battery icon indicates
that the capacity of the rechargeable battery is low. The balance will be ready to
operate for about another 10 hours, then it will switch off automatically.
“BAT LO“ appearing on the display indicates that the capacity of the battery is
exhausted. The balance will be ready to operate for about another 50 minutes, then it
will switch off automatically. To charge the chargeable battery, connect the mains
cable.
The LED display informs you during loading about the loading status of the
rechargeable battery.
6.6 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). 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.
Strictly observe hints in chapter Adjustment.
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6.7 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.
The adjustment is locked for verified balances. Carrying out adjustment
requires that the seal is destroyed and the adjusting switch is confirmed in
step 3 when turning on the scale. For position of adjusting switch, see chpt.
6.8.1.
Attention:
After destruction of the seal the balance must be re-verified by an
authorised agency and a new verification wire/seal mark fitted before it can
be reused for applications subject to verification.
Procedure when adjusting:
Observe stable environmental conditions. A warming up time (see chapter 1) is
required for stabilization. Ensure that there are no objects on the weighing plate.
1. Switch-on balance and during the selftest press .
2. Use the numeric keys to enter „0000“ for a password and confirm by .
Ø
3. Adjustment function F0 CAL is shown. Press the adjusting switch and confirm by
pressing .
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4. Ensure that there are no objects on the weighing plate. Wait for stability display,
then press . The required adjustment weight is shown.
5. Place the adjustment weight carefully in the centre of the weighing pan, press
and the adjusting process will be started.
Ø
Ø
6. The adjustment process has been successfully completed. Take away
adjustment weight.
7. Press and the scales will return to weighing mode.
ÖIn case of an adjustment error or incorrect adjusting weight the display will
show an error message (SPAN / FAKL), repeat adjustment process.
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6.8 Verification
General hints:
According to EU directive 90/384/EEC balances must be officially verified if they are
used as follows (legally controlled area):
a) For commercial transactions if the price of goods is determined by weighing.
b) For the production of medicines in pharmacies as well as for analyses in the
medical and pharmaceutical laboratory.
c) For official purposes.
d) For manufacturing final packages.
In cases of doubt, please contact your local trade in standard.
After verification the balance is sealed at the indicated positions.
Verification of the balance is invalid without the "seal".
Verification notes
An EU type approval exists for balances described in their technical data as
verifiable. If a balance is used where obligation to verify exists as described above, it
must verified and re-verified in regular intervals.
Re-verification of a balance is carried out according to the respective national
regulations. The validity for verification of balances in Germany is e.g. 2 years.
The legal regulation of the country where the balance is used must be observed!
Balances with obligation to verify must be taken out of operation if:
•The weighing result of the balance is outside the error limit. Therefore, in
regular intervals load balance with known test weight (ca. 1/3 of the max. load)
and compare with displayed value.
•The reverification deadline has been exceeded.

6.8.1 Position of seals and adjusting switch
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1
2
3
1
2
4
1. Seal of approval
2. Cover
3. Housing screw
4. Adjustment switch
6.9 Checking the balance verification settings
For the adjustment, the balance must be switched over to service mode.
In the service mode the parameters of the balance can be modified.
The service parameters may not be modified, as this could damage the
balance settings.
In calibrated scales the service mode is locked individually for each switch.
To disable the access lock, destroy the seal and confirm the swatch (See chpt. 6.9.1
step 3). For position of switch see chpt. 6.8.1.
Attention:
After destruction of the seal the balance must be re-verified by an authorised agency
and a new verification wire/seal mark fitted before it can be reused for applications
subject to verification.

6.9.1 Service mode
This overview of the service parameters is merely for checking the parameters set by
the appropriate Bureau of Standards. No changes may be made.
Access to menu:
1. Switch-on balance and during the selftest press .
2. Use the numeric keys to enter „0000“ for a password and confirm by .
Ø
3. The first function „F0 CAL“ is displayed. Press adjusting switch.
Select function:
ÖYou can select individual functions containing the current settings one after the
other by using or a numeric key (i.e. 0 for F0 or 2 for F2).
Change / save settings:
ÖConfirm selected function by pressing . Select desired setting by pressing
and confirm by pressing or cancel by pressing .
Exit menu:
ÖUsing the balance returns into the weighing mode.
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Overview for service parameter:
Factory settings are marked by [*].
Function
ÆÄ
Settings
Æ
Description
CAL F0 CAL Adjustment function, see chpt. 6.7
CAL F1 rES Resolution
rES 1 3000* Always use this setting
rES 1 6000
rES dual rAnge
CAL F2 P Unit Unit
Unit 100G oFF
Unit 100G on* Always use this setting
CAL F3 CAP Weighing range (max)
CAPA 6 Factory setting RFS 6K2HM
CAPA 15 Factory setting RFS 15K5HM
CAPA 30 Factory setting RFS 30K10HM
CAPA 45
CAL F4 dESC Position decimal point
”weight display“
0.000 Point
Factory setting
RFS 6K2HM / RFS 15K5HM
0.00 Point Factory setting RFS 30K10HM
0.0 Point
0 Point
CAL F5 PdESC
Point FiXEd*
FLoAt
Position decimal point
“price displays”
CAL F6 P div Interval size currency
Min Coin 1*
Min Coin 2
Min Coin 5
Min Coin 10
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CAL F7 rEtAre
rE tArE on
rE tArE off*
Follow up tare ON/OFF
CAL F8 CoUntS Display internal resolution
XXX A-d CoUntS
CAL F9 Coin Currency
Set CUrr 1 €
Set CUrr 2 £
Set CUrr 3 Kč
Set CUrr 4 PLN
CAL F10 FormaAt Printout configuration
CHAr LEntH 1
CHAr LEntH 2
Print Format 1
Print Format 2
Printout examples, see chpt. 10.1
Print Format 3 No printer function
CAL F11 PLU Not documented
Print PLU
CAL F12 Pin P1 Not documented
CAL F135 rS232 RS232 Interface ON/OFF
rS232 on*
rS232 oFF
CAL F14 Grv Not documented
* = default setting

7 Basic Operation
7.1 Switching on/off
ÖTo turn on/off confirm forward at the underneath on the right of the scale and
keep pressed for a little while. The balance will carry out a self-test The balance
is ready for weighing when the weight display appears.
ÖTo switch-off push backward the switch-on/switch-out on the right lower side of
the balance.
7.2 Zeroing
Resetting to zero corrects the influence of light soiling on the weighing plate.
ÖUnload the balance
ÖPress , the balance starts resetting to zero.
The [T]symbol over aappears.
7.3 Taring
ÖDeposit weighing vessel. After successful stop check press the button.
The zero display and the [T]symbol over NET will appear.
The weight of the container is now internally saved.
ÖWeigh the material, the net weight will be indicated.
ÖThe weight of the weighing container will be displayed as a minus number after
removing the weighing container.
ÖTo delete the tare value, remove load from weighing plate and press .
7.4 Overload warning
Overloading exceeding the stated maximum load (max) of the balance, minus a
possibly existing tare load, must be strictly avoided. This could cause damage to
the balance.
Exceeding maximum load is indicated by the display of „-OL-“ and an audio
sound. Unload balance or reduce preload.
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