KERN MPE 250K100HNM User manual

KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: [e-mail]
Tel: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Service Manual
Personal floor scale with BMI function
KERN MPE_HNM / MPE_PNM
Type MPE 250K100HNM
Type MPE 250K100PNM
Version 1.0
07/2018
GB
MPE_HNM / MPE_PNM -SH-e-1810

2 MPE_HNM / MPE_PNM -SH-e-1810
GB
KERN MPE_HNM / MPE_PNM
Version 1.0 07/2018
Servicemanual
Contents
1Basic Information........................................................................................... 3
2Appliance overview ....................................................................................... 4
3Keyboard overview........................................................................................ 6
4Overview of display....................................................................................... 7
4.1 Balance assembly and installation ............................................................................................. 7
4.2 Mains connection........................................................................................................................ 7
4.3 Battery operation is possible by obtaining an optional battery power pack. .............................. 8
4.4 Battery operation........................................................................................................................ 9
4.5 Insert batteries............................................................................................................................ 9
5The menu...................................................................................................... 10
5.1 Navigation in the menu............................................................................................................. 10
5.2 Menu overview ......................................................................................................................... 11
6Data output RS 232...................................................................................... 14
6.1 Pin allocation of balance output bushing:................................................................................. 14
6.2 Technical data .......................................................................................................................... 14
6.3 Position adjustment switch and seals:...................................................................................... 15
6.4 Verification validity period (current status in G)........................................................................ 15
7Adjustment................................................................................................... 16
7.1 Procedure:................................................................................................................................ 17
8MAINTENANCE ............................................................................................ 19
8.1 General..................................................................................................................................... 19
8.2 Error Codes .............................................................................................................................. 19
8.3 Determine the Problem............................................................................................................. 20
8.4 Check the Load cell.................................................................................................................. 21
8.5 Checking the different Voltages ............................................................................................... 21
8.6 Trouble Shooting ...................................................................................................................... 22
9Replace Main Board..................................................................................... 23
10 DRAWING ..................................................................................................... 24
10.1 MPE_HM .................................................................................................................................. 24

MPE_HNM / MPE_PNM -SH-e-1810 3
1 Basic Information
The device must be repaired only by trained specialist staff or personnel with
professional formation (such as a repair-specialist accredited by law concerning
verification). The service manual is obligatory for repair work. After repair, original
conditions of the device have to be restored. Only original spare parts should be
used.
Instructions about conformity-evaluated scales:
Repair must be carried only at 100% compliance with the type approval. A violation
of this specification will result in a loss of the type approval! After successful repair
the balance will have to be reverified before it can be used again in a statutorily
regulated field.
The operation and configuration of each scale is described in the accompanying
manual of the scale. Any safety information in respect for verification are also
described in the accompanying manual
This service manual covers the MPE_HNM / MPE_PNM series and is edited for the
authorized servicing personnel.
Note all rights are reserved. Copying any part of this manual is prohibited without our
permission.
For operation, please use the operating instructions corresponding to the device

4 MPE_HNM / MPE_PNM -SH-e-1810
2 Appliance overview
1. Height measuring stick
(MPE-HM models only)
2. Display Unit
3. Weighing platform
(anti-slip surface)
4. Rubber feet
(height adjustable)
Underside
5.Rolls

MPE_HNM / MPE_PNM -SH-e-1810 5
Secondary display at rear
Display unit at rear
5 Rechargeable battery
compartment
6 Mains connection
7 RS 232 C

6 MPE_HNM / MPE_PNM -SH-e-1810
3 Keyboard overview
Type MPE 250K100HNM
Type MPE 250K100PNM
Key
Description
Function
ON/OFF-switch
Turn on/off
HOLD button
Hold function/Calculation of a stable weight value
BMI key
Calculation of the Body Mass Index
PRINT button
Data transfer via interface
In menu:
Confirm selection
For numeric entry:
Confirm numerical value
Function key
In menu:
Call up menu
How to 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

MPE_HNM / MPE_PNM -SH-e-1810 7
4 Overview of display
Display
Description
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
4.1 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.
4.2 Mains connection
Power is supplied by the external power unit which also serves to isolate 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 is completely discharged
blue:
Charging rechargeable battery

8 MPE_HNM / MPE_PNM -SH-e-1810
4.3 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 switching off in order to save battery (s. operating instructions
corresponding to the device chap. 11.6 Auto off).Load rechargeable battery.
Voltage has dropped below prescribed minimum.
Rechargeable battery very low.
Rechargeable battery completely reloaded
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

MPE_HNM / MPE_PNM -SH-e-1810 9
4.4 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 operating instructions corresponding to the device chap.11.6 Auto off).
Capacity of batteries exhausted.
Batteries will soon be flat.
Batteries are completely charged
4.5 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.

10 MPE_HNM / MPE_PNM -SH-e-1810
5 The menu
Access to service menu „tCH“ is locked in verified weighing scales.
To disable the access lock, destroy the seal and actuate the
adjustment switch. For position of adjustment switch, see operating
instructions corresponding to the device chap. 16.
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.
5.1 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 pressing .The current
setting will be displayed.
To select the desired setting, press and confirm
your selection by ; the weighing scale will return to
the menu.
Exit menu/
Return to weighing
mode
Press and the scales will return to weighing mode.

MPE_HNM / MPE_PNM -SH-e-1810 11
5.2 Menu overview
Menu block
Main Menu
Menu item
Submenu
Available settings / explanation
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
oFF
Not documented
Prt
Pr ACC
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 results
S: Send stable weighing result
T: Tare
Z: Zero setting
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 Baudrate: 600, 1200, 2400, 4800, 9600

12 MPE_HNM / MPE_PNM -SH-e-1810
3. Data output format
(P Prt, P Auto, P Cont settings only)
the currently set data output format will be shown after the
baud rate was confirmed. Select desired format by and
confirm with .
Only when set P Prt, P Auto
Prt 0-3
Data output format, see chap. 13.
Only when set P Cont
Cont 1
Default
Sd0 –on/off
Cont. data outputselectable
„send 0“, yes / no
Cont 2
Not documented
Cont 3
Not documented
4. Printer type
After the data output format has been confirmed, the currently set
printer type will be displayed.
Select the desired printer type by and confirm by .
LP -50
Not documented
tPUP
Usethissetting
Background
illumination
bl on
Back lighting for display on
bl oFF
Display background illumination off
bl AU*
Backlighting for display will come on automatically as
soon as the weighing scale is operated.
Subsequent tare
value
locked in devices
with type approval
certificate.
Str on
Subsequent tare ON
Str oFF*
Subsequent tare OFF

MPE_HNM / MPE_PNM -SH-e-1810 13
Service menu
Pin
Password entry: press , ,
subsequently.
Operate adjustment switch; for position see operating instructions corresponding to the
device chap.17
Display speed
15*
Not documented
30
60
7.5
Adjustment, see operating instructions corresponding to the
device chap. 18
tri*
Not documented
CoUnt
Not documented
rESEt
Reset weighing scale to factory setting
SEtGrA
Not documented
* default setting

14 MPE_HNM / MPE_PNM -SH-e-1810
6 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 operating
instructions corresponding to the device chap. 12.1)
In a medical context only auxiliary equipment in compliance with Directive
EN 60601-1 may be connected to the interface.
6.1 Pin allocation of balance output bushing:
Pin 2: TXD - Output
Pin 3: RXD - Input
Pin 5: GND - Signal ground
6.2 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,

MPE_HNM / MPE_PNM -SH-e-1810 15
6.3 Position adjustment switch and seals:
1. Self-destroying seal mark
2. Cover
3. Adjustment switch
6.4 Verification validity period (current status in G)
Personal scales (including chair and wheelchair scales) in
hospitals
4 year
Personal scales, when not located in hospitals (for example,
doctor's offices and nursing homes)
unlimited
Baby weighing scales and mechanical birth weight scales
4 year
Bed scales
2 year
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.
(Details derived from: „Information by the verification authority, weighing scales
applied in medical use“)
3
2
1

16 MPE_HNM / MPE_PNM -SH-e-1810
7 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.
Prepare 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. Information about test weights you will find in the
internet under http://www.kern-sohn.com
Observe stable environmental conditions. For warm-up time required for
stabilisation see operating instructions corresponding to the device
chap. 1.
Access to service menu „tCH“ is locked in verified weighing scales.
To disable the access lock, destroy the seal and actuate the adjustment
switch. Position of the adjustment switch see operating instructions
corresponding to the device 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.

MPE_HNM / MPE_PNM -SH-e-1810 17
7.1 Procedure:

In weighing mode, press repeatedly until [tCH] appears.
Press and [Pin] will appear.
Press , and one after the other and [P1 SPd] will
appear

Press , „P2 CAL“ will be displayed
Operate adjustment switch; for position see chap.16
Press and [dESC] will appear
Press repeatedly until „CAL“ will be displayed.
To confirm, press and [UnloAd] will appear
Ensure that there are no objects on the weighing pan.
Wait until the stability display „STABLE“ is displayed and then
confirm by pressing .
(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 by pressing and [LoAd] will be displayed.

18 MPE_HNM / MPE_PNM -SH-e-1810

Place adjustment weight in the centre of the weighing pan
Wait until stability display „STABLE“ appears
Confirm by pressing , [PASS] will be 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.

MPE_HNM / MPE_PNM -SH-e-1810 19
8 MAINTENANCE
8.1 General
If the scale does not operate properly, find out the problem as possible.
Determine whether the problem is constant or alternate. Be aware that problems can
be caused by mechanical or electrical influences.
Check the following.
Water
Corrosive materials
Vibrations or temperature or wind
Physical damage
Check the scale cables for damage, and check all connections and connecters for
any loose contact or incorrect connection
8.2 Error Codes
Error Message
Description
Solution
-----
Maximum load exceeded
Unload or reduce weight
Err 1
Incorrect date
Enter the date by using format
“yy;mm:dd”
Err 2
Incorrect time
Enter the time by using format
“hh:mm:ss”
Err 4
Zero setting error
Zero setting range exceeded
due to switching on.(4%max)
Make sure platform empty.
Err 5
Key board error
Check the keys and
connecter.
Err 6
A/D value out of range
Make sure platform empty and
check the pan is installed
proper. Check the load cell
connectors.
Err 7
Percentage Error
Please check input data, must
be > 0.5d
Err 8
Calibration weight error
Check the test weights for
calibration or linear calibration
Err 9
Unstable Reading
Check any air variation,
vibration, RF noise and
touching some where.
Check the load cell and
connecters.
Err 10
Wireless communiation
failure
Check wireless settings or
change Com settings from the
wireless
Err 11
Communication protocol
error
Check communication settings

20 MPE_HNM / MPE_PNM -SH-e-1810
Err 12
Accumulation error
Max accumulation times 99 /
999 / weight 999999
Err 13
Lack of unit weight
Check unit weight entry data,
must be >0.5d
Err 14
Lack of sample
Check counting samples
entry, must be >20d
Err 15
Gravity error
Check the gravity settings.
Gravity range must be 0.9xx ~
1.0xx
Err 16
Paper error
Check the printer paper
Err 17
Tare out of range
Minus weight or overload.
Remove the load and restart
scale again.
Err 18
Pre-tare error
Check the pre-tare value
Err19
Initialize zero error
Calibration the scale.
Err P
Printer error
Check the printer settings or
connections
Err l
Approval setting error
Check the PCB jumper
settings. Must be connect
jumper pin to K1 (BW series)
--ol--
Over range
Remove the load.
Re calibrate
--lo--
Underload
Minus weight, check the
platform and restart or
calibrate.
Fai l h /
fai l l / fai
l
Calibration Error
Check the test weights & Re
calibrate
Ba lo /
lo ba
Battery low
Re charge battery, check the
voltages.
8.3 Determine the Problem
Determine whether the problem is in the PCB or the Load Cell
Disconnect the power supply from the scale, and disconnect the load cell
connection from the PCB
Reapply power and test the PCB
If problem goes away, its source is probably in the Load cell. Check the wiring,
connecter, load cell and mechanical components of the load cell.
If problem persists, its source is probably in the PCB. Check the PCB
voltages, connecters, cables and function programs