KERN RPB-DM 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 manual
Price calculating balance
KERN RFC
Type: RPB-DM
Version 1.3
2021-04
GB
RFC-BA-e-2113

2 RFC-BA-e-2113
GB
KERN RFC
Version 1.32021-04
Operating manual
Price calculating balance
Contents
1Technical data................................................................................................ 4
1.1 Dimensions (mm) ....................................................................................................................... 8
2Declaration of conformity ............................................................................. 9
3Appliance overview ..................................................................................... 10
3.1 Overview of display .................................................................................................................. 11
3.2 Keyboard overview................................................................................................................... 13
4Basic Information (General)........................................................................ 14
4.1 Proper use................................................................................................................................ 14
4.2 Improper Use............................................................................................................................ 14
4.3 Warranty................................................................................................................................... 14
4.4 Monitoring of Test Resources .................................................................................................. 14
5Basic Safety Precautions............................................................................ 15
5.1 Pay attention to the instructions in the Operation Manual........................................................ 15
5.2 Personnel training..................................................................................................................... 15
6Transport and storage................................................................................. 15
6.1 Testing upon acceptance ......................................................................................................... 15
6.2 Packaging / return transport..................................................................................................... 15
7Unpacking, Setup and Commissioning ..................................................... 16
7.1 Installation Site, Location of Use.............................................................................................. 16
7.2 Unpacking................................................................................................................................. 16
7.2.1 Placing...................................................................................................................................... 17
7.2.2 Scope of delivery / serial accessories:..................................................................................... 17
7.3 Mains connection...................................................................................................................... 17
7.4 Storage battery operation (optional)......................................................................................... 17
7.5 Initial Commissioning................................................................................................................ 18
7.6 Adjustment................................................................................................................................ 18
7.7 Verification................................................................................................................................ 21
7.7.1 Adjustment switch and seals.................................................................................................... 22
7.8 Checking the balance verification settings............................................................................... 22
8The menu...................................................................................................... 23
8.1 Access to menu........................................................................................................................ 23
8.2 Navigation in the menu:............................................................................................................ 23
8.3Menu overview ......................................................................................................................... 24
9Operation...................................................................................................... 26
9.1 Turn on/off ................................................................................................................................ 26
9.2 Zeroing ..................................................................................................................................... 26
9.3 Weighing with tare.................................................................................................................... 26
9.4 Overload warning ..................................................................................................................... 26
10 Weighing with price determination ............................................................ 27
10.1 Piece price entry via keyboard ................................................................................................. 27
10.2 Memory for piece price (PLU = Price look up) ......................................................................... 28
11 Additional useful functions......................................................................... 30
11.1 Enter piece price and calculate the total price (without weighing) ........................................... 30

RFC-BA-e-2113 3
11.2 AUTO CLEAR........................................................................................................................... 30
11.3 Display background illumination............................................................................................... 31
11.4 Units switch-over from € / kg € / 100g.................................................................................. 31
11.5 When used as a checkout........................................................................................................ 32
11.5.1 Preparation........................................................................................................................... 32
12 RS 232 interface........................................................................................... 34
12.1 Technical data .......................................................................................................................... 34
12.2 Pin allocation of balance output bushing:................................................................................. 34
12.3 Remote control commands ...................................................................................................... 34
12.4 Explanation of the data transfer ............................................................................................... 35
12.5 Print .......................................................................................................................................... 35
13 Servicing, maintenance, disposal .............................................................. 36
13.1 Cleaning ................................................................................................................................... 36
13.2 Servicing, maintenance............................................................................................................ 36
13.3 Disposal.................................................................................................................................... 36
14 Instant help................................................................................................... 37
14.1 Error messages ........................................................................................................................ 38

4 RFC-BA-e-2113
1 Technical data
Models without vertical display:
KERN (Typ) TRFC 3K3M-A RFC 6K3M
Model RPB 3K3DM RPB 6K1DM
Weighing range (max) 3 kg 3 kg / 6 kg
Readability (d) 1 g / 2 g 1 g / 2 g
Minimum load (Min) 20 g 20 g
Verification value (e) 0.5 g / 1 g 1 g / 2g
Verification class III III
Reproducibility 1 g / 2 g 1 g / 2 g
Linearity ± 3 g / ± 6 g ± 3 g / ± 6 g
Recommended adjusting
weight (not supplied) 3 kg (M1) 6 kg (M1)
Stabilisation time 2 s
Heating time (operating
temperature) 10 min
Net weight (kg) 2.8 kg 4.1 kg
Piece
price, can be switched
over €/kg; €/100 g
Admissible
ambient temperature -10° C to 40° C
Allowable air humidity 0 % - 80 % (non-condensing)
Electric Supply Mains adapter 220 V - 240 V AC, 50 Hz
balance 12 V, 500 mA
Rechargeable battery
(optional) 6 V, 3.2 Ah
Operating time – background lighting OFF 60 hrs.

RFC-BA-e-2113 5
KERN (Typ) RFC 15K3M RFC 30K3M
Model RPB 15K2DM RPB 30K5DM
Weighing range (max) 6 kg / 15 kg 15 kg / 30 kg
Readability (d) 2 g / 5 g 5 g / 10 g
Minimum load (Min) 40 g 100 g
Verification value (e) 2 g / 5g 5 g / 10 g
Verification class III III
Reproducibility 2 g / 5 g 5 g / 10 g
Linearity ± 2 g /± 5 g ± 5 g /± 10 g
Recommended adjusting
weight (not supplied) 15 kg (M1) 30 kg (M1)
Stabilisation time 2 s
Heating time (operating
temperature) 10 min
Net weight (kg) 4.1 kg
Piece
price, can be switched
over €/kg; €/100 g
Admissible
ambient temperature -10° C to 40° C
Allowable air humidity 0 % - 80 % (non-condensing)
Electric Supply Mains adapter 220 V - 240 V AC, 50 Hz
balance 12 V, 500 mA
Rechargeable battery
(optional) 6 V, 3.2 Ah
Operating time – background lighting OFF 60 hrs.

6 RFC-BA-e-2113
Models with post-mounted display:
KERN (Typ) TRFC 3K3HM-A RFC 6K3HM
Model RPB 3K3DHM RPB 6K1DHM
Weighing range (max) 3 kg 3 kg / 6 kg
Readability (d) 1 g / 2 g 1 g / 2 g
Minimum load (Min) 20 g 20 g
Verification value (e) 0.5 g / 1 g 1 g / 2 g
Verification class III III
Reproducibility 1 g / 2 g 1 g / 2 g
Linearity ± 3 g / ± 6 g ± 3 g / ± 6 g
Recommended adjusting
weight (not supplied) 3 kg (M1) 6 kg (M1)
Stabilisation time 2 s
Heating time (operating
temperature) 10 min
Net weight (kg) 2.8 kg 4.1 kg
Piece
price, can be switched
over €/kg; €/100 g
Admissible
ambient temperature -10° C to 40° C
Allowable air humidity 0 % - 80 % (non-condensing)
Electric Supply Mains adapter 220 V - 240 V AC, 50 Hz
balance 12 V, 500 mA
Rechargeable battery
(optional) 6 V, 3.2 Ah
Operating time – background lighting OFF 60 hrs.

RFC-BA-e-2113 7
KERN (Typ) RFC 15K3HM RFC 30K3HM
Model RPB 15K2DHM RPB 30K5DHM
Weighing range (max) 6 kg / 15 kg 15 kg / 30 kg
Readability (d) 2 g / 5 g 5 g / 10 g
Minimum load (Min) 40 g 100 g
Verification value (e) 2 g / 5 g 5 g / 10 g
Verification class III III
Reproducibility 2 g / 5 g 5 g / 10 g
Linearity ± 6 g /± 15 g ± 15 g / ± 30 g
Recommended adjusting
weight (not supplied) 15 kg (M1) 30 kg (M1)
Stabilisation time 2 s
Heating time (operating
temperature) 10 min
Net weight (kg) 4.1 kg
Piece
price, can be switched
over €/kg; €/100 g
Admissible
ambient temperature -10° C to 40° C
Allowable air humidity 0 % - 80 % (non-condensing)
Electric Supply Mains adapter 220 V - 240 V AC, 50 Hz
balance 12 V, 500 mA
Rechargeable battery
(optional) 6 V, 3.2 Ah
Operating time – background lighting OFF 60 hrs.

8 RFC-BA-e-2113
1.1 Dimensions (mm)
Models without vertical display:

RFC-BA-e-2113 9
Models with post-mounted display:
2 Declaration of conformity
The current EC/EU Conformity declaration can be found online in:
www.kern-sohn.com/ce

10 RFC-BA-e-2113
3 Appliance overview
Models without vertical display:
Models with post-mounted display:
1. Weighing pan
2. Bubble level
3. Post-mounted display
4. Footscrews
5. Mains adapter connection
6. ON/OFF switch
7. RS 232 interface
8. Battery compartment
9. Adjustment switch

RFC-BA-e-2113 11
3.1 Overview of display
Operator and secondary display (standard on the backside of models without
post-mounted display):
Additional post-mounted display for models with tripod:
1. Weight
2. Piece price
3. Sales price

12 RFC-BA-e-2113
Display weight
Here, the weight of your goods is displayed.
Indicator

next to symbol displays:
Rechargeable battery very low
NET Net weight
Stability display
Zeroing display
Display piece price
Piece price, can be switched over from € / kg or € / 100 g.
Indicator

next to symbol displays:
€ / kg Piece price in €/kg
€ / 100 g Piece price in €/100 g
AUTO CLEAR Set piece price is deleted automatically when
balance is unloaded
When used as a POS system, this function of unit price switching is
not available. (depending on the “DLG-06” protocol setting)
Display sale price
Here the sales price is displayed in Euro [€].
Battery loading status display
red Charging storage battery
green Rechargeable battery completely reloaded

RFC-BA-e-2113 13
3.2 Keyboard overview
Selection
Function
~
•Numerical keys, PLU-keys
•In menu: Invoke parameter
•Delete
•Save piece price (press key for a long time),
see chap. 10.2
•Call-up piece price (press and hold key for a short time),
see chap. 10.2
•Switch-over unit € / kg

€ / 100g
•Issue to external device
•In menu: Parameter selection
•Taring, see chap. 9.3
•In menu: Storing settings
•For activated function, the set piece price is automatically
deleted when the balance is unloaded.
•Enter piece price per piece (without weighing)
•Zeroing
•In menu: Back to weighing mode
Depending on the operation mode (F4 PdESC):
•decimal point (PdESC FloAt)
•
double zero (PdESC Fix)

14 RFC-BA-e-2113
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 centre of the weighing
pan. As soon as a stable weighing value is reached the weighing value can be read.
4.2 Improper Use
Do not use balance for dynamic weighing. In the event that small quantities are
removed or added to the material to be weighed, incorrect weighing results can be
displayed due to the “stability compensation“! (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.
4.3 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
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 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.

RFC-BA-e-2113 15
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 personnel.
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
platform, power unit etc. against shifting and damage.

16 RFC-BA-e-2113
7 Unpacking, Setup 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.
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.
7.2 Unpacking
Carefully remove the balance from the packaging, remove plastic cover and setup
balance at the intended workstation.

RFC-BA-e-2113 17
7.2.1 Placing
Level balance with foot screws until the air bubble of the
water balance is in the prescribed circle.
7.2.2 Scope of delivery / serial accessories:
•Balance, see chap. 3
•Mains adapter
•Protective cover
•Operating manual
7.3 Mains connection
Power is supplied via the external mains adapter. The stated voltage value must be
the same as the local voltage.
Only use KERN original mains adapter. Using other makes requires consent by
KERN.
7.4 Storage battery operation (optional)
The optionally supplied battery is charged with the supplied power supply.
Before the first use, the battery should be charged by connecting it to the mains
power supply for at least 15 hours.
•If an arrow []appears on the weight display above the battery symbol , the
capacity of the rechargeable battery will soon be exhausted. The balance will be
ready to operate for about another 10 hours, then it will switch off automatically.
Charge the battery with the help of the supplied power pack.
•If in the weight display appears „bat Lo“ followed by a flickering display, the
capacity of the rechargeable battery is below the prescribed minimum. The
balance will be ready to operate for about another 5 minutes, then it will switch off
automatically. Charge the battery with the help of the supplied power pack.
The LED display informs you during loading about the loading status of the
rechargeable battery.
red: Battery is almost discharged
green: Rechargeable battery completely reloaded

18 RFC-BA-e-2113
7.5 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. 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.
7.6 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.
The adjustment is locked for verified balances. Carrying out adjustment
requires that the seal is destroyed and the adjustment switch is confirmed in
step 3 when turning on the scale. For position of adjustment switch, see
chap. 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.

RFC-BA-e-2113 19
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 pan.
Arrange adjustment weight, details see chap.1 „Techn. data“
To turn on/off operate the on/off switch at the
underneath side on the right of the scale and
keep pressed for a little while. During the selftest
press and keep pressed until Pn is
displayed.
Use the numeric keys to enter the standard
password 0000. Pn---- is displayed.
Confirm password with , the adjustment
function F0 CAL will be displayed.
Press adjustment switch on the lower side of the balance.
Press , UnLoAd will be displayed. Ensure
that there are no objects on the weighing pan.
Press again, CAP LOADxx will be
displayed.
(example)

20 RFC-BA-e-2113
Set the displayed adjustment weight with the help
of . Place the adjustment weight. Wait for
the stability display appears,
then press . PASS will be displayed.
Remove the adjustment weight. F0 CAL appears
on the display. Now the process of adjustment is
successfully completed. Return to weighing mode
using
In case of an adjustment error or incorrect adjustment weight, the display will
show an error message, then repeat adjustment process.