KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: info@kern-sohn.com
Phone: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Operating manual
Multi-function weighing balance
KERN MWA-M / MWA-PM
Version 1.4
04/2016
GB
MWA-M / MWA-PM-BA-e-1614
2 MWA-M / MWA-PM-BA-e-1614
GB
KERN MWA 300K1M / MWA 300K1PM
Version 1.4 04/2016
Operating manual
Multi-function weighing balance
Contents
1 Technical data ............................................................................................ 4
2 Declaration of conformity .......................................................................... 5
2.1 Explanation of the graphic symbols ........................................................................ 5
3 Appliance overview .................................................................................... 7
4 Keyboard overview .................................................................................... 9
5 Overview of display .................................................................................. 10
6 Basic instructions .................................................................................... 11
6.1 Specific function ....................................................................................................11
6.2 Proper use ............................................................................................................11
6.3 Improper Use ........................................................................................................12
6.4 Warranty ...............................................................................................................12
6.5 Monitoring of Test Resources ...............................................................................12
7 Basic Safety Precauti on s ........................................................................ 13
7.1 Pay attention to the instructions in the Operation Manual ......................................13
7.2 Personnel training .................................................................................................13
7.3 Preventing contamination ......................................................................................13
8 Electromagnetic comp at ib ility (EMC) ..................................................... 14
8.1 General hints ........................................................................................................14
8.2 Electromagnetic interf erences ...............................................................................15
8.3 Electromagnetic noise immunity ............................................................................
16
8.3.1 Crucial features of performance ........................................................................................... 18
8.4 Minimum distances ...............................................................................................18
9 Transport and storage ............................................................................. 19
9.1 Testing upon acceptance ......................................................................................19
9.2 Packaging / return transport ..................................................................................19
10 Unpacking, Setup and Commissioning .................................................. 20
10.1 I nstallation Site, Location of Use ...........................................................................20
10.2 Unpacking .............................................................................................................20
10.3 Scope of delivery ..................................................................................................21
10.4 Balance assem bly and installation ........................................................................21
10.4.1 Application examples: .......................................................................................................... 21
10.5 Mains connect ion ..................................................................................................22
10.6 Battery operation is possible by obtaining an optional battery power pack ............23
10.7 Battery operation ...................................................................................................24
10.8 I n itial Commissioning ............................................................................................26
MWA-M / MWA-PM-BA-e-1614 3
11 Operation .................................................................................................. 26
11.1 Weighing ...............................................................................................................26
11.1.1 Weighing with wheelchair ..................................................................................................... 27
11.2 Taring ...................................................................................................................27
11.3 HOLD function ......................................................................................................28
11.4 Displa y additional last decimal place .....................................................................29
11.5 Calculation of the Body Mass Index ......................................................................29
11.5.1 Calculating Body Mass Index ............................................................................................... 29
11.5.2 Classification of BMI values ................................................................................................. 30
11.6 Automatic switch-off function „AUTO OFF“ ...........................................................31
11.7 Displa y background illumination ............................................................................32
12 Menu .......................................................................................................... 33
12.1 Navigation in t he menu .........................................................................................33
12.2 Menu overview ......................................................................................................34
13 Data output RS 232 .................................................................................. 36
13.1 Pin allocation of balance output bushing: ..............................................................36
13.2 Technical data ......................................................................................................36
13.3 Print er operation ...................................................................................................37
14 Error messages ........................................................................................ 37
15 Servicing, maintenance, disposal ........................................................... 38
15.1 Cleaning ...............................................................................................................38
15.2 Clea n ing / disinfecting ...........................................................................................38
15.3 Servicing, maintenance .........................................................................................38
15.4 Disposal ................................................................................................................38
16 Instant help ............................................................................................... 39
17 Verification ................................................................................................ 40
17.1 Verif icat ion validity period (current status in G) .....................................................42
18 Adjustment ............................................................................................... 43
4 MWA-M / MWA-PM-BA-e-1614
1 Technical data
KERN
MWA
300K1M
MWA
300K1PM
Display 6-digit
Weighing range (max) 300 kg
Minimum load (Min) 2 kg
Verification value (e) 100 g
Reproducibility 0.1 kg
Linearity ± 0.1 kg
Display LCD with 25mm high digits
Recommended adjustment
weight, (Class)
300 kg
(M1)
Stabilization time (typical) 2 sec.
Warm-up time 10 min
Operating temperature - 10° C …. + 40° C
Humidity of air max. 80 % (not condensing)
Electric Supply Input voltage 100V-240V AC, 50 / 60 Hz
Auto Off After 3, 5, 15, 30 min without load change (adjustable)
Dimensions
fully assembled
(D x W X H) mm
1190 x 1140 x 80 1190 x 1140 x 1150
Weighing plate (W x D) mm 880 x 840
Weight kg (net) 72 76
Rechargeable battery
operation
Optional
Batteries 6 x 1.5 V AA
Data interface
provided as standard
RS 232 C
MWA-M / MWA-PM-BA-e-1614 5
2 Declaration of conformity
To view the current EC/EU Declaration of Conformity go to:
www.kern-sohn.com/ce
The scope of delivery for verified weighing balances (= conformityrated weighing balances) includes a Declaration of Conformity.
Solely these weighing balances are classified as medical devices.
2.1 Explanation of the graphic symbols
This marking indicates that these weighing balances are in
conformity with EU Directive 2014/31/EU for non-automatic
weighing balances. Weighing balances bearing this
marking are licensed for medical purposes in the European
Union.
The number inside the frame“M16“ (example shown year
16) documents the year of conformity assessment.
This marking shows that this weighing balance is in
conformity with EU Directive 93/42/EEC and inside the
European Community is classified as medical device.
WF 150012
Designation of the serial number of every device, applied at the
device and on the packaging
Number here as example
2016-03
Identification of the manufacturing date of the medical product.
Year and month here as example
“Please note the accompanying documents“
or “Please note operating instructions”
6 MWA-M / MWA-PM-BA-e-1614
“Observe operating instructions”
“Observe operating instructions”
Kern & Sohn GmbH
D–72336 Baligen,German y
www.kern-sohn.com
Identification of manufacturer of medical product including
address
“Electro-medical appliance“
with attachment for type B
Device protection category II
Dispose of old appliances separately from your household
waste!
Instead, take them to communal collection points.
Temperature limit indicating the upper and the lower limit
(storage temperature on packaging)
(Temperature serving as an example)
12 V DC / 500 mA
Display of supply voltage for scales with polarity display.
Safety instruction: Do not place hands beneath the ramp.
+70°C
-30°C
MWA-M / MWA-PM-BA-e-1614 7
3 Appliance overview
The wheelchair platform scale MWA-M with folded
and unfolded ramps and the display (serial fitting).
The wheelchair platform scale
MWA-PM with folded and
unfolded ramps, the display and
the rail with a stand (serial
fitting).
The possibility of retrofitting with
2nd rail MWA-A02 (without a
stand).
Folded wheelchair platform
scale MWA-PM.
8 MWA-M / MWA-PM-BA-e-1614
Weighing balance suitable as
wheelchair or stand assist
balance.
1. Display Unit
2. Handrail optional
MWA-A01with tripod
(cannot be retrofitted)
MWA-A02 without tripod
3. Ramps
4. Bubble level
5. Carrying handle
Wheelchair balance
(Collapsible ramps)
Suitable as wheelchair and
stand assist balance
Handrail collapsible
Display unit back
6. Adjustment switch
7. Terminal power supply unit
8. Connecting cable
”display unit - platform"
9. Connector RS232
MWA-M / MWA-PM-BA-e-1614 9
4 Keyboard overview
Button Designation Function
ON/OFF button Turn on/off
Hold-key
Print-key
Hold function /determination of stable weighing value
Print (press and hold for a while): Data transmission via
interface RS 232
BMI key
Determination of body mass index
In the menu:
• Confirm selection
For numeric entry:
• Confirm numerical value
Function key
In menu:
• Call up menu
• Select menu items
For numeric entry:
• Increase numerical value
Zeroing key
Weighing scale will be reset to „0.0“
For numeric entry:
• Change decimal place
TARE key Tare balance
10 MWA-M / MWA-PM-BA-e-1614
5 Overview of display
Display Designation Description
Stability display Scales are in a steady state
Zeroing display Should the balance not display exactly
zero despite empty weighing plate, press
the button. Your balance will be set
to zero after a short standby time.
NET Net weight display Illuminated when net weight is displayed
Illuminated after weighing scale was
tared
GROSS Gross weight display Illuminated when gross weight is
displayed
HOLD HOLD function HOLD function active
BMI BMI function Illuminated while BMI function is enabled
Rechargeable /Battery
display
Shows the capacity of the rechargeable /
batteries
MWA-M / MWA-PM-BA-e-1614 11
6 Basic instructions
Weighing instruments have to be verified for the purposes stated
below in accordance with Directive 2009/23/EC.
Article 1,
paragraph 4. “Determination of mass in the practice of medicine
that is, weighing patients for reasons of medical supervision
during medical surveillance, examination and treatment.”
6.1 Specific function
Indication
Determining the body weight in the medical practice area.
Use as „non-standalone weighing scale“, that is, a person
steps carefully onto the weighing platform‘s centre. Once a
steady display value is shown, you can read the weight value.
For weighing with a wheelchair, the wheelchair and the person
sitting on it are pushed over the ramp onto the centre of the
weighing platform or, in the case of an electric wheelchair, the
patient and wheelchair move independently onto the weighing
platform. Once a steady display value is shown, you can read
the weight value.
Contraindication
No contraindication known
6.2 Proper use
This weighing balance is designed for determining the weight of persons in a
standing or sitting position in medical treatment rooms. The balance is suitabl e for
recognising, preventing and controlling illnesses.
On multi-function balances, the weighed person should step onto the centre of the
weighing platform and remai n stan di ng w it hout mov i ng . For weighing with a
wheelchair, the wheelchair should be placed in the centre of the weighing platform.
As soon as a stable weighing value is reached the weighing value can be read.
The weighing scale is designed for continuous duty.
The weighing platform may only be stepped on by persons
capable of standing on both feet on the weighing platform.
The balance should be checked for correct condition prior to each utilisation by a
person familiar with proper operation of the balance.
12 MWA-M / MWA-PM-BA-e-1614
6.3 Improper Use
Do not use these scales for dynamic weighing processes.
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 weighing
plate, minus a possibly existing tare load, must be strictly avoided. This could cause
damage to the balance.
Never operate balance in explosive environment. The serial version is not explosion
protected. It should be noted that a flammable mixture of anaesthetics and oxygen or
laughing gas may occur.
The structure of the balance may not be modified. This may lead to incorrect
weighing results, safety-related fault s and des tr uc ti on o f the bala nce.
The balance may only be used according to the described conditions. Other areas of
use must be released by KERN in writing.
6.4 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 and damage caused by media, liquids,
• Natural wear and tear
• The appliance is improperly set up or incorrectly electrically connected
• The measuring system is overloaded
• Dropping the balance
6.5 Monitoring of Test Resources
In the framework of quality assurance the measuring-related weighing 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.
MWA-M / MWA-PM-BA-e-1614 13
7 Basic Safety Precautions
7.1 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.
7.2 Personnel training
The medical staff must apply and follow the operating instructions for proper use and
care of the product.
7.3 Preventing contamination
The prevention of cross-contamination (fungal skin infections,……) requires regular
cleaning of the weighing platform. Recommendation: after a weighing procedure that
could potentially result in contamination (e. g. after weighing that involves direct skin
contact).
14 MWA-M / MWA-PM-BA-e-1614
8 Electromagnetic compatibility (EMC)
8.1 General hints
The installation and use of the electrical multi-function balances MWA
requires special precautionary measures as outlined in the EMC
information below.
This device complies with the limits set for medical electrical devices of group 1,
class B (as per EN 60601-1-2).
Electromagnetic compatibility (EMC) describes a device’s ability to perform reliably
within an electromagnetic environment without causing inadmissible electromagnetic
interference at the same time. Amongst other things, such disturbances may be
emitted by connecting cables or the air.
Inadmissible disturb ances from the environment may result in incorrect displays,
inaccurate measured values or incorrect behaviour of the multi-function balances
MWA. The multi-function balances MWA, too, may in certain cases cause such
malfunctions in other devices. To eliminate problems of that kind, we recommend you
to take one or several of the measures listed below:
• Change the alignment or distance of the device to the source of failure.
• Install and use the multi-function balances MWA in one and the same place.
• Connect the multi-function balances MWA to a separate power source.
• For further questions please contact our customer services.
Disturbances may be caused by improper modification or add-ons to the device or
not recommended accessories (such as power units or connecting cables) . The
manufacturer will not be responsible for these. Modifications may also result in a loss
of authorisation relating to the use of the device.
Devices emitting high frequency signals (mobile telephones, radio
transmitters, radio receivers) may cause interference in the multifunction balances MWA. Do not use these near multi-function
balances MWA. Chapter 8.4 contains details about recommended
minimum distances.
MWA-M / MWA-PM-BA-e-1614 15
8.2 Electromagnetic interferences
Guidelines and manufacturer’s declaration – electromagnetic interferences
The multi-function balances MWA are intended for operation in the kind of electromagnetic
environment stated below. The customer or user of the multi-function balances MWA should
ensure that they are operated in this kind of environment.
Emitted interference
measurements
Conformity
Electromagnetic environment guideline
HF emissions
as per CISPR 11 / EN 55011
Assembly 1
The multi-function balances MWA
apply HF energy exclusively for
their internal function.
Their HF
emission therefore is very low and
it is highly unlike to interfere with
adjacent electronic devices.
HF emissions
as per CISPR 11 / EN 55011
Class B
The multi-function balances MWA
are designed for use in all
equipment including those in living
areas and those connected directly
to the public power grid that also
supplies buildings used for living
purposes.
Emission of harmonics
acc. to IEC 61000-3-2
Class A
Emission of voltage fluctuations /
flicker
acc. to IEC 61000-3-3
Conforms with
Do not stack or operate multi-function balances MWA immediately next to or together
with other devices. If this type of operation is necessary, observe the multi-function
balances MWA to ensure normal operation in such an arrangement.
16 MWA-M / MWA-PM-BA-e-1614
8.3 Electromagnetic noise immunity
Guidelines and manufacturer’s declaration - electromagnetic noise immunity
The multi-function balances MWA are intended for operation in the kind of electromagnetic
environment stated below. The customer or user of the multi-function balances MWA should ensure
that they are operated in this kind of environment.
Noise immunity tests
IEC 60601 test level
Conformity
Electromagnetic
environment - guideline
Discharge static
electricity (DSE)
acc. to IEC 61000-4-2
± 6 kV contact discharge
± 8 kV air discharge
± 6 kV
± 8 kV
Floors should be made of
wood or concrete or tiled with
ceramic tiles.
If floors are
covered with synthetic
material, relative air humidity
must be at least 30%.
Fast transient electrical
disturbances / bursts
acc. to IEC 61000-4-4
± 2 kV for power lines
+ 1 kV for input and
output lines
± 2 kV
+ 1 kV
The quality of the supply
voltage should match that of
the typical business or
hospital environment.
Impulse voltages /
surges
acc. to IEC 61000-4-5
± 1 kV voltage
Live wire - live wire
± 2 kV voltage
Live wire - earth
± 1 kV
Inapplicable
The quality of the supply
voltage should match that of
the typical business or
hospital environment.
Voltage dips, short-term
disruptions and
fluctuations in supply
voltage
acc. to IEC 61000-4-11
< 5 %
(> 95 % dip of )
for ½ period
40 %
(> 60 % dip of )
for 5 periods
70 %
(> 30 % dip of )
for 25 periods
< 5 %
(> 95 % dip of )
for 5 s
Compliance
with
requirements
under all
postulated
conditions
Controlled
switch off
Return to
undisturbed
situation
after user
intervention.
The quality of the supply
voltage should match that of
the typical business or
hospital environment.
If the
user demands continued
functioning of multi-function
balances MWA even after the
occurrence of a power failure,
we recommend using
uninterruptible means of
power supply or batteries for
the multi-function balances
MWA.
Magnetic field for supply
frequency
(50/60 Hz)
acc. to IEC 61000-4-8
3 A/m
3 A/m
50/60 Hz
Magnetic fields for the supply
frequency should match the
typical values found in the
particular business or hospital
environment.
NOTE equals AC line voltage prior to application of test level.
MWA-M / MWA-PM-BA-e-1614 17
Guidelines and manufacturer’s declaration - electromagnetic noise immunity
The multi-function balances MWA are intended for operation in the kind of electromagnetic
environment stated below. The customer or user of the multi-function balances MWA should ensure
that they are operated in this kind of environment.
Noise immunity
tests
IEC 60601 test level
Conformity
Electromagnetic environment guideline
Conducted HF
disturbance
variables
acc. to IEC 61000-4-
6
3
150 kHz to 80 MHz
3 V
Do not use portable or mobile radio
sets nearer to the multi-function
balances MWA or their wires than the
distance recommended as safety
distance which is calculated according
to the equation relevant for its
transmission frequency.
Recommended safety distance:
for 80 MHz to 800 MHz
for 800 MHz up to 2.5 GHz
Use P as rated capacity of radio
transmitter in Watt (W) as per details
given by the radio transmitter
manufacturer and d as recommended
safety distance in metres (m).
The field intensity of stationary radio
transmitters should for all frequencies
be lower according to an in situ
a
examination than the conformity level.
b
Interference may occur near devices
bearing the symbol below.
Emitted HF
disturbance
variables
Acc. to IEC 61000-43
3
80 MHz to 2.5 GHz
3 V/m
NOTE 1 Higher frequency range applies to 80 MHz and 800 MHz.
NOTE 2 These guidelines may not be applicable in all cases.
The spread of electromagnetic variables is influenced by absorption and
reflections in buildings, objects and hum ans .
a
The field intensity of stationary radio transmitters such as base stations of wireless telephones and
mobile radio sets, amateur radio stations, AM and FM radio and television stations cannot be
reliably predicted in advance.
To determine the electromagnetic environment in respect of
stationary transmitters, you should consider a study of electromagnetic phenomena at the location.
If the measured field intensity at the location where the balance is to be used exceeds the
conformity level above, you should observe the multifunctional balances MWA in order to ensure
normal operation. If you observe unusual features of performance you may have to take additional
measures such as a change in alignment or a different location for the multifunctional balances
MWA.
b
For a frequency range of 150 kHz to 80 MHz field intensity should be less than 3 V/m.
18 MWA-M / MWA-PM-BA-e-1614
8.3.1 Crucial features of performance
Note:
The multifunctional balances MWA do not have any crucial features of
performance as per IEC 60601-1. The system may be subject to
interference by other devices even if these devices conform to current
emission requirements as per CISPR.
8.4 Minimum distances
Recommended safety distance between portable and mobile HF
telecommunication devices and multi-function balances MWA
The multi-function balances MWA are designed for use in an electromagnetic environment in
which HF disturbance variables are controlled. The customer or user of the multi-function
balances MWA can help avoiding electromagnetic disturbances by keeping the minimum
distance between portable and mobile HF telecommunication devices (transmitters) and the
multi-function balances MWA – depending on the output performance of the communication
device, as stated below.
Rated capacity of
transmitter
W
The safety distance depends on the transmission
frequency
m
150 kHz up to 80
MHz
80 MHz up to 800
MHz
800 MHz up to 2.5
GHz
0.01
0.12
0.12
0.23
0.1
0.38
0.38
0.73
1
1.20
1.20
2.30
10
3.80
3.80
7.30
100
12.00
12.00
23.00
For transmitters with a maximum rated capacity not stated in the table above you can
calculate the recommended safety distance in metres (m) yourself by using the equation
belonging to each column, whereby P equals the maximum rated capacity of the transmitter
in Watt (W) as per details provided by the transmitter manufacturer.
NOTE 1 Higher frequency range applies to 80 MHz and 800 MHz.
NOTE 2 These guidelines may not be applicable in all cases.
The spread of electromagnetic variables is influenced by absorption and
reflections in buildings, objects and humans.
MWA-M / MWA-PM-BA-e-1614 19
9 T ransport and storage
9.1 Testing upon acceptance
When receiving the appliance, please check packaging immediately, and the
appliance itself when unpacking for possible visible damage.
9.2 Packaging / return transport
Keep all parts of the original packaging for a possibly required
return.
Only use original packaging for returning.
Prior to dispatch disconnect all cables and remove loose/mobile
parts.
Reattach possibly supplied transport securing devices.
Secure all parts such as the weighing platform, power unit etc.
against shifting and damage.
20 MWA-M / MWA-PM-BA-e-1614
10 Unpacking, Setup and Commissioning
10.1 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 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 dampne s s for long er per iods o f time.
Non-permitted condensation (co nd ens a ti on o f air humidi ty 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 the balance and of the person to be weighed.
• Avoid contact with water.
Major display deviations (incorrect weighing results) may be experienced should
electromagnetic fiel ds (e.g. due to mobile phones or radio equipment), static
electricity accumulations or instable power supply occur. Change location or remove
source of interference.
10.2 Unpacking
Remove the individual components of the balance or the complete balance from the
packaging with care and install at the intended location. When using the power pack,
ensure that the power cable does not produce a risk of stumbling.
MWA-M / MWA-PM-BA-e-1614 21
10.3 Scope of delivery
Serial accessories:
• Balance
• Mains adapter (in conformity with EN 60601-1)
• Operating manual
• Wall bracket
• Small components
4 x
2 x
10.4 Balance assembly and installation
Level balance with foot screws until the air bubble of the
water balance is in the prescribed circle.
Check levelling regularly.
The weighing balance to be used as wheelchair balance is delivered fully assembled.
1 handrail with tripod (MWA-A01) or 1 handrail without tripod (MWAS-A02) ar e
optionally available for additional use as stand assist balance (See chap.3 device
overview). The handrails are also suitable for use in connection with wheelchairs.
10.4.1 Application examples:
Weighing balance used as
Wheelchair balance stand assist balance with handrail MWS-
A01
22 MWA-M / MWA-PM-BA-e-1614
Assembly handrail MWA-A02 (optional):
Screw down handrail (MWAA02) on the frame, using the
four screws
Note:
After fitting the attachments and before using the weighing balance, check
all attachments for firm fit.
10.5 Mains connection
Power is supplied by the external power unit which also serves to isol ate the mains
supply from the scale. The stated voltage value must be the same as the local
voltage.
Always use genuine approved KERN power pack units as per EN 60601-1 directive.
The small sticker attached to the side of the display unit indicates the power port:
The LED remains illuminated as long as the weighing scale remains connected to the
mains.
The LED display informs you during loading about the loading status of the
rechargeable battery.
green: Rechargeable battery completely reloaded
blue: Charging storage battery
MWA-M / MWA-PM-BA-e-1614 23
10.6 Battery operation is possible by obtaining an optional battery power pack
Open the battery compartment cover (1) at the base of the display unit and insert the
rechargeable battery. Charge the battery for at least 12 hours before initial use.
The appearance of the symbol in the weight display indicates that the battery
is almost exhausted. The weighing scale will remain ready for operation for a few
more minutes before sw i tchi ng off in order to save battery. Load rechargeable
battery.
Voltage has dropped below prescribed minimum.
Rechargeable battery very low.
Rechargeable battery completely reloaded
Right underneath the display there is a LED with the symbol .
If the LED lights green, the rechargeable battery is fully charged. If it is lighting blue,
it is being charged.
If the balance is not used for a longer time, take out the rechargeable battery and
store it separately. Leaking liquid could damage the balance.
1
24 MWA-M / MWA-PM-BA-e-1614
10.7 Battery operation
As an alternative to rechargeable battery operation, the balance may also be
operated with 6x AA batteries.
Open battery compartment cover (1) at the lower side of the display unit and insert
batteries according to the example below. Lock the battery cover again. If the
batteries are empty, in the balance display appears the symbol . Change
batteries. To save battery power, the balance switches off automatically (see
chap.11.6 Auto off).
Capacity of batteries exhausted.
Batteries will soon be flat.
Batteries are completely charged
MWA-M / MWA-PM-BA-e-1614 25
Insert batteries
Remove battery compartment cover
Connect battery holder to housing
contact acc. to illustration
Insert battery holder
Insert batteries into battery
compartment and lock with battery
compartment cover.
26 MWA-M / MWA-PM-BA-e-1614
10.8 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) and be switched on.
The accuracy of the balance depends on the local acceleration of gravity.
The value of gravity acceleration is shown on the type plate.
11 Operation
11.1 Weighing
Start balance by pressing .
The balance will carry out a self-test
The scales are ready for operation as soon as the weight
display for “0.0 kg“ has appeared.
However, you can reset the weighing scale to zero by pressing
the key.
Have person stand in the centre of the scales. Wait until the
standstill display „STABLE“ appears, then read the weighing
result.
If the person is heavier than the weighing range, "OL"
(=overload) will appear in the display.
MWA-M / MWA-PM-BA-e-1614 27
11.1.1 Weighing with wheelchair
Place wheelchair and patient in the centre of the weighing balance.
Engage brakes on wheelchair
Do not leave the patient unattended
Wait until patient is sitting still and read weighing value 1.
Loosen the brakes and carefully pull off the transportation stretcher/wheelchair
with patient
Then weigh the wheelchair without the patient and deduct the result from
weighing value 1, from this follows the weight for the patient.
11.2 Taring
The tare weight of any preloads can be deducted by pressing a button so that the
actual weight of the person is displayed in subsequent weighings.
(example)
Put an object (such as a towel, support or empty wheelchair)
on the weighing pan.
Press , the zero display appears.
„NET” is shown at the bottom on the left.
(example)
Allow the person to step onto the centre of the weighing
platform.
Wait until the standstill display „STABLE“ appears, then read
the weighing result.
W hen the balance is unloaded the saved taring value is
displayed with negative sign.
To delete the stored tare value, release scales and press
.
28 MWA-M / MWA-PM-BA-e-1614
11.3 HOLD function
The balance has an integrated standstill function (mean value calculation). With this
function it is possible to weigh people accurately even if they do not stand still on the
weighing plate.
Start balance by pressing .
Wait for stability display „STABLE to appear.
(example)
Press , in the display „---------“ will appear and the
„HOLD“ symbol appears.
Allow the person to step onto the centre of the weighing
platform.
After a short time the stability display „STABLE“ appears and
the weighing value of the person is displayed and „frozen“.
After unloading the balance, the weighing value remains
displayed for approx. 10 seconds, than the balance changes
automatically into the weighing mode.
The „HOLD“ symbol disappears.
There is no average value calculation in the event of too much
movement.
MWA-M / MWA-PM-BA-e-1614 29
11.4 Display additional last decimal place
(short-time, additional decimal place)
Press and hold for about 2 s whilst weighed result is being shown. The second
decimal place will be shown for approx. 5 s.
This value is not considered as ver i fie d and may not be use d for th e purp os e o f a
verified balance.
11.5 Calculation of the Body Mass Index
You need to know a person’s body height before you can calculate the BMI for that
person. This should be known.
11.5.1 Calculating Body Mass Index
Start balance by pressing
Wait for stability display „STABLE to appear.
Press .
The most recently entered body height will be shown with the
enable digit flashing. The BMI symbol lights up.
To enter body height, press the and key.
Confirm entered value by . BMI „0.0“ is displayed
Allow the person to step onto the centre of the weighing
platform.
„---------„ is shortly displayed, followed by the BMI v alue of the
person.
Unload weighing plate
Return to weighing mode using
The BMI symbol will disappear and the kg display will
reappear.
30 MWA-M / MWA-PM-BA-e-1614
• Reliable calculation of BMI is restricted to a body height of 100 cm to 200
cm and a weight of >10 kg.
• If weighing has to take place under unsteady conditions, you can be
stabilise the display by applying the Hold function.
11.5.2 Classification of BMI values
Weight classification for adults over 18 years of age using the BMI in accordance
with WHO, 2000 EK IV and WHO 2004.
Categorie BMI ( kg/m2) Risk of diseases associated with
overweight
Underweight < 18.5 low
Normal weight 18.5 – 24.9 Average
Overweight
Pre-adipose
Adipose degree I
Adipose degree II
Adipose degree III
> 25.0
25.0 – 29.9
30.0 – 34.9
35.0 – 39.9
> 40
A bit high
Increased
High
Very high
MWA-M / MWA-PM-BA-e-1614 31
11.6 Automatic switch-off function „AUTO OFF“
The weighing scale will switch off automatically after the allotted time as long as
neither the display unit nor the weighing plate is operated.
• Menu settings:
[F1 oFF] [oFF 0/3/5/15/30] (see chap. 12)
(example)
(example)
In weighing mode, press and the fir st fu ncti o n [F1 oFF]
will be displayed.
Press , the last saved time is displayed, for example,
[oFF 15]
Press repeatedly until the desired time is displayed,
e.g. [oFF 30]
[oFF 0] AUTO OFF - function disabled
[oFF 3]
Weighing system will be turned off a fter 3 min .
[oFF 5]
Weighing system w i l l be turned off after 5 mi n .
[oFF 15]
Weighing system will be turned off a fter 15 mi n.
[oFF 30]
Weighing system will be turned off a fter 30 mi n.
Save selected time with , [F1 oFF] is displayed
Return to weighing mode using
32 MWA-M / MWA-PM-BA-e-1614
11.7 Display background illumination
• Menu settings:
[F2 bk] [bL on / bL oFF / bL AU] see chap. (12)
(example)
In weighing mode, press and the fir st fu ncti o n [F1 oFF]
will be displayed.
Press until [F 2 bk] is displayed.
Press , the last saved setting is displayed, for example
[bL on]
To select the desired setting, press
With save select setting , [F2 bk] is displayed.
Return to weighing mode using
bL on Continuous background lighti ng
bL off Background illumination off
bL Auto Automatic background illumination on when weighing pate is
loaded or key pressed.
MWA-M / MWA-PM-BA-e-1614 33
12 Menu
Access to service menu „tCH“ is locked in verified balances.
To disable the access lock, destroy the seal and actuate the
adjustment switch. For position of adjustment switch, see chap. 17.
Attention:
After destruction of the seal the weighing system 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.
12.1 Navigation in the menu
Call up menu
In weighing mode, press and the first function [F1
oFF] will be displayed.
Select function
With help of , the individual functions can be
selected one after the other.
Change settings
Confirm selected function by . The current setting
will be displayed.
Select desired setting by and confirm with ,
the balance returns to the menu.
Exit menu/
Return to weighing
mode
Press , the balance will return to weighing mode.
34 MWA-M / MWA-PM-BA-e-1614
12.2 Menu overview
Function
Settings
Description
Automatic cutout
Auto Off
oFF 0*
Automatic shutdown off
oFF 3
Automatic shutdown after 3 min.
oFF 5
Automatic shutdown after 5 min.
oFF 15
Automatic shutdown after 15 min.
oFF 30
Automatic shutdown after 30 min.
Background
illumination
of display
oFF*
Not documented
Prt
Pr ACC
Background
illumination
of display
bl on
Back lighting for display on
bl oFF
Display background illum ination of f
bl AU*
Backlighting for display will come on automatically as
soon as the weighing scale is operated.
Interface parameter
1.
RS-232 mode
Select desired mode by , then confirm with .
P Prt
Weight will be added to summation memory and printed
after pressing PRINT
P Cont Continuous data output
Series
Not documented
ASK
Remote control instructions:
W: Send all weighing details
S: Send stable weight value
T: Taring
Z: Zeroing
P cnt 2
Not documented
P Stab
Automatic data output of stable weighing values
P Auto
Weighed result will be added automatically to summation
memory and issued
2. Baud rate
The currently set baud rate (b xxx) will be shown after the RS-232 mode was
confirmed.
Select desired Baudrate by pressing and confirm by pressing
. Available Baud rate: 600, 1200, 2400, 4800, 9600
MWA-M / MWA-PM-BA-e-1614 35
3.
Data output format
(Setting P Prt, P Auto, P Cont only!)
The currently set data output format will be displayed after the Baud rate has
been confirmed. Select desired format by and confirm with .
only at
setting
P Prt, P
Prt 0-3
Data output format, see chap. 13
Only when set
P Cont
Cont 1 Default
Sd0 – on/off
Continuous data output,
selectable “Sending 0” yes /
no
Cont 2
Not documented
Cont 3
Not documented
4. Printer type
The currently set printer type will be displayed after the data output format
has been confirmed.
Select desired printer type by pressing and confirm with .
LP 50
Not documented
tPUP
Use this setting
Service menu
Pin
Password Input: press , ,
subsequently.
Operate adjustment switch; for position see chap.15
Display speed
15*
Not documented
30
60
7.5
Adjustment, see chap. 18
tri*
Not documented
CoUnt
Not documented
rESEt
Reset weighing scale to factory setting
SEtGrA
Not documented
36 MWA-M / MWA-PM-BA-e-1614
13 Data output RS 232
You can print weighing data automatically via the RS 232 interface or manually by
pressing via the interface according to the setting in the menu.
This data exchange is asynchronous using ASCII - Code.
The following conditions must be met to provide successful communication between
the weighing balance and the printer.
• Use a suitable cable to connect the weighing balance to the interface of the
printer. Faultless operation requires an adequate KERN interface cable.
• Communication parameters (baud rate, bits and parity) of balance and printer
must match. For detailed description of interface parameters see chap. 13.2)
13.1 Pin allocation of balance output bushing:
Pin 2: TXD - output
Pin 3: RXD - input
Pin 5: GND - signal ground
13.2 Technical data
Connection 9 pin d-subminiature bushing
Pin 2 output
Pin 3 input
Pin 5 signal earth
Baud rate Optional 600/1200/2400/4800/9600
Parity 8 bits
MWA-M / MWA-PM-BA-e-1614 37
13.3 Printer operation
Printout examples:
Prt
0 / 2 60.0kg
1 / 3
60.0kg
170.0cm
20.7BMI
14 Error messages
Display
Description
Zero range exceeded
(on start-up or when pressing the key)
• Load on weighing pan
• Excess load, during zero setting of weighing scale
• Incorrect adjusting process
• Fault on load cell
Value outside the A/D converter range
• Damaged weighing cell
• Damaged electronics
Should other error messages occur, switch balance off and then on again. If the error
message remains inform manufacturer.
38 MWA-M / MWA-PM-BA-e-1614
15 Servicing, maintenance, dis pos al
15.1 Cleaning
Before any maintenance, cleaning and repair work disconnect the
appliance from the oper ati ng vol tage.
15.2 Cleaning / disinfecting
Clean weighing platform (such as seat) as well as casing with household detergents
or commercially available disinfectants. Please follow manufacturer’s instructions.
Do not use abrasive or aggressive cleaners such as spirits or alcohol or similar as
they might damage the high-quality surface.
The prevention of cross-contamination (fungal skin infections,……) requires regular
cleaning of the weighing platform. Recommendation: after a weighing procedure that
could potentially result in contamination (e. g. after weighing that involves direct skin
contact).
Do not spray disinfectants onto appliance.
Make sure that disinfectant does not penetrate the interior of
the appliance.
Remove dirt immediately.
15.3 Servicing, maintenance
The appliance may only be opened by trained service technicians who are authorized
by KERN.
Disconnect the scales before openi ng .
15.4 Disposal
Disposal of packaging and appliance must be carried out by operator according to
valid national or regional law of the location where the appliance is used.
MWA-M / MWA-PM-BA-e-1614 39
16 Instant help
In case of an error in the program process, briefly turn off the balance and disconnect
from power supply. The weighing process must then be restarted from the beginning.
Fault Possible cause
The displayed weight does
not glow.
• The balance is not switched on.
• The mains supply connection has been
interrupted (mains cable not plugged in/faulty).
• Power supply interrupted.
• Rechargeable battery inserted incorrectly or
empty
• No rechargeable battery inserted
The displayed weight is
permanently changing
• Draught/air movement
• Table/floor vibrations
• The weighing plate is in contact with foreign
bodies or is not correctly positioned.
• Electromagnetic fields / static charging (choose
different location/switch off interfering device if
possible)
The weighing result is
obviously incorrect
• The display of the balance is not at zer o
• Adjustment is no longer correct.
• Great fluctuations in temperature.
• Warm-up time was ignored.
• Electromagnetic fields / static charging (choose
different location/switch off interfering device if
possible)
Should other error messages occur, switch balance off and then on again. If the error
message remains inform manufacturer.
40 MWA-M / MWA-PM-BA-e-1614
17 Verification
General introduction:
According to EU directive 2009/23/EC balances must be officially verified if they are
used as follows (legal ly control l ed 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.
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 be verified and re-verified at regular intervals.
Re-verification of a balance is carried out according to the respective national
regulations. For verification validity period, s. chap. 17.1.
The legal regulation of the country where the balance is used must be observed!
Verification of the balance is invalid without the seal.
The seal marks attached on balances with type approval point out that the
balance may only be opened and serviced by trained and authorised
specialist staff. If the seal mark is destroyed, verification looses its validity.
Please observe all national laws and legal regulations. In Germany a reverification will be necessary.
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.
MWA-M / MWA-PM-BA-e-1614 41
Position adjustment switch and seals
1. Self-destroying seal mark
2. Cover
3. Adjustment switch
42 MWA-M / MWA-PM-BA-e-1614
17.1 Verification validity period (current status in G)
Multi-function balances (including chair and wheelchair scales)
in hospitals
4 years
Multi-function balances, when not located in hospitals (for
example, doctor's offices and nursing homes)
unlimited
Baby weighing scales and mechanical birth weight scales 4 years
Bed scales 2 years
Scales in dialysis stations unlimited
Rehab clinics and health authorities are treated as hospitals
(4 years of verification validity)
Not treated as hospitals (verification validity not limited) are dialysis stations, nursing
homes and doctor’s surgeries.
(Data source : ”Bureau of Standards News, Weighing Instruments in Medicine“}
MWA-M / MWA-PM-BA-e-1614 43
18 Adjustment
As the acceleration value due to gravity is not the same at every location on earth,
each display unit with connected weighing plate 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 weighing system 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 display unit periodically in weighing operation.
• Pr epar e the required adjustment weight. The adjustment weight to be
applied depends on the capacity of a weighing scale, see chap. 1.
Carry out adjustment as closely as possible to admissible maximum
load of weighing scale. Info about test weights can be found on the
Internet at: http://www.kern-sohn.com.
• Observe stable environmental conditions.
For warm-up time required for stabilisation see chap. 1.
Access to service menu „tCH“ is locked in verified balances.
To disable the access lock, destroy the seal and actuate the adjustment
switch. Position of the adjustment switch see chap. 17.
Attention:
After destruction of the seal the weighing system 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:
In weighing mode, press repeatedly until [tCH]
appears.
Press , [Pin] is displayed
44 MWA-M / MWA-PM-BA-e-1614
Press , and one after the other, [P1 SPd] will
appear
Press , „P2 CAL“ will be displayed
Operate adjustment switch; for position see chap.16
Press , [dESC] is displayed
Press repeatedly until [CAL] will be displayed.
Confirm with , [UnloAd] appears
Ensure that there are no objects on the weighing pan.
Wait for stability display "STABLE", then confirm with
(example)
The size of the currently set adjustment weight will be
displayed.
To change, select the digit to be altered by , and the
numerical value by .
Confirm with , [LoAd] appears.
MWA-M / MWA-PM-BA-e-1614 45
Place adjustment weight in the centre of the weighing pan
Wait until stability display „STABLE“ appears
Confirm with [PASS] is displayed.
The balance carries out a selftest, after that [Err19]
will be displayed and a signal will sound.
Switch off the balance
Take away adjustment weight
Turn on balance again, after the selftest the balance changes
into the weighing mode. Adjustment has now been completed
successfully.
Loading...