KERN MCC-NM User manual

KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: info@kern-
sohn.com
Tel: +49-[0]7433-
9933-0
Fax: +49-[0]7433-9933-
149
Internet: www.kern-
sohn.com
Service Manual
Medical Chair scale
KERN MCC-NM
Type MCC 250K100NM
Version 1.0
07/2018
GB
MCC-NM-SH-e-1810

2 MCC-NM-SH-e-1810
GB
KERN MCC-NM
Version 1.0 07/2018
Servicemanual
Content
1Basic Information........................................................................................... 3
2Introdution...................................................................................................... 3
3Appliance overview ....................................................................................... 4
3.1 Overview of display .................................................................................................................... 7
3.2 Keyboard overview..................................................................................................................... 8
3.3 Installing the chair scales ........................................................................................................... 9
3.3.1 Levelling ................................................................................................................................... 10
3.4 Mains connection...................................................................................................................... 12
3.4.1 Safety cable.............................................................................................................................. 12
3.5 Rechargeable battery operation............................................................................................... 13
3.6 Battery operation...................................................................................................................... 13
3.7 Initial Commissioning................................................................................................................ 14
4Menu ............................................................................................................. 15
4.1 Navigation in the menu............................................................................................................. 15
4.2 Menu overview ......................................................................................................................... 16
5Verification ................................................................................................... 17
5.1 Verification validity period (current status in G)........................................................................ 18
6Adjustment................................................................................................... 19
7 ............................................................................................................................... 21
8 ............................................................................................................................... 21
9 ............................................................................................................................... 21
10 ............................................................................................................................. 21
11 MAINTENANCE ............................................................................................ 22
11.1 Service, maintenance............................................................................................................... 22
11.2 Error Codes .............................................................................................................................. 22
11.3 Check the Load cell.................................................................................................................. 23
11.4 Checking the different Voltages ............................................................................................... 23
11.5 Trouble Shooting ...................................................................................................................... 25
12 DRAWING ..................................................................................................... 27

MCC-NM-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
2 Introdution
This service manual covers the MCC 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.

4 MCC-NM-SH-e-1810
3 Appliance overview
1. Seat pan
2. Bubble level
3. Display Unit
4. Manipulations
5. Parking brake
6. Adjustment switch
7. Terminal power supply unit
8. Connection cable "Display - Chair"
9. Battery compartment

MCC-NM-SH-e-1810 5
Details:
Parking brake open
Parking brake closed
Foot rest and adjustment foot
Accessory bag

6 MCC-NM-SH-e-1810
Folding arm rests

MCC-NM-SH-e-1810 7
4 Overview of display
Display
Description
Description
GROSS
Gross weight display
Lights up during indication of the gross
weight
NET
Net weight display
Lights up during indication of the net weight
Illuminated after weighing scale was tared
ZERO
Zeroing display
Should the balance not display exactly zero
despite empty scale pan, press the
button.Your balance will be set to zero after a
short standby time.
STABLE
Stability display
Scales are in a steady state
BMI
Body Mass Index
Is actively displayed during active BMI
function
HOLD
HOLD function
Is displayed with active hold function
Rechargeable battery
symbol
Lights when the voltage drops below the
prescribed minimum.
Lights when the rechargeable battery
capacity is almost exhausted.
Lights when the rechargeable battery is fully
charged.

8 MCC-NM-SH-e-1810
4.1 Keyboard overview
Key
Description
Function
ON/OFF-switch
Turn on/off
HOLD button
Hold function
BMI key
Calculation of the Body Mass Index
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
Zero setting key
Weighing scale will be reset to „0.0“
For numeric entry:
Change decimal place
TARE key
Tare balance

MCC-NM-SH-e-1810 9
4.2 Installing the chair scales
Place scales on an even surface.
Check if the air bubble of the level is within the prescribed circle.
If the air bubble of the bubble level is not in the required circle, level the
balance using the adjustment feet as specified in the following chapter
8.4.1:
Check levelling regularly.

10 MCC-NM-SH-e-1810
4.3 Levelling
Levelling is restricted to specialist staff possessing well acquainted
with the workings of weighing scales.
Place scales on an even surface.
Lock brakes
Turn the wheel (1) until the air bubble of the bubble level is in the black
circle
Turn the counternuts (2) right to the top.

MCC-NM-SH-e-1810 11
Gap width must not exceed 15 mm!
Use the adjustment feet to fix the chair at the front rollers

12 MCC-NM-SH-e-1810
4.4 Mains connection
Terminal power supply unit
Power is supplied via the external mains adapter.The printed voltage must
correspond to the local voltage.
Only approved genuine KERN power supply units may be used in compliance with
Directive EN 60601-1.
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 provides information about the battery's charging status.
Green: battery is fully charged
Blue: battery is charging
4.5 Safety cable
Safety cable for strain relief of the mains cable.
Application:
Installation for strain relief between mains cable (plug-in power supply unit) and
display unit.

MCC-NM-SH-e-1810 13
4.6 Rechargeable battery operation
Open the battery compartment cover (1) at the base of the display unit and insert the
rechargeable battery pack.
Charge the battery for at least 12 hours before initial use.
The appearance of the symbol in the weight display indicates that the battery
packs is almost exhausted.The weighing scale will remain ready for operation for a
few more minutes before switching off in order to save battery.Charge the battery
pack.
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 battery pack and store it
separately.Leaking liquid could damage the balance.
4.7 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
1

14 MCC-NM-SH-e-1810
4.8 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.
4.9 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 balances 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.

MCC-NM-SH-e-1810 15
5 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. 15.
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 .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 and the scales will return to weighing mode.

16 MCC-NM-SH-e-1810
5.2 Menu overview
Function
Settings
Description
F1 oFF
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
F2 bk
Background
illumination
of display
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.
F3 Str
Subsequent tare
value, locked in
devices with
type approval
certificate.
Str on
Following tare ON
Str oFF*
Following tare OFF
tCH
Service menu
Pin
It display shows "Pin" adjust switch.
Then press subsequently , ,
P1 Spd
Display speed
15*
Not documented
30
60
7.5
P2 CAL
Adjustment, see chap. 16.1
P3 Pro
tri*
Not documented
CoUnt
Not documented
rESEt
Reset weighing scale to factory setting
SEtGrA
Not documented
* default setting

MCC-NM-SH-e-1810 17
6 Verification
General introduction:
According to EU directive 2014/31/EU balances must be officially verified if they are
used as follows (legally controlled area):
a) For commercial transactions if the price of goods is determined by weighing.
b) For the production of medicines in pharmacies as well as for analyses in the
medical and pharmaceutical laboratory.
c) For official purposes
d) For manufacturing final packages
e) Determination of mass in the practice of medicine that is, weighing patients for
reasons of medical supervision during medical surveillance, examination and
treatment.
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. 15.1.
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 loses its
validity.Please observe all national laws and legal regulations.In Germany a
re-verification 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.

18 MCC-NM-SH-e-1810
6.1 Position adjustment switch and seals:
1. Self-destroying seal mark
2. Cover
3. Adjustment switch
6.2 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“)

MCC-NM-SH-e-1810 19
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 MCC-NM Instruction manual see chpt 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 MCC-NM Instruction manual
chap. 15.
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.

20 MCC-NM-SH-e-1810
7.1 Procedure:

In weighing mode, press repeatedly until [tCH] appears.
Press , [Pin] is displayed
Press , and subsequently, [P1 SPd] will appear

Press , „P2 CAL“ will be displayed
Operate adjustment switch; for position see MCC-NM
Instruction manual chap.15
Press , [dESC] is displayed
Press repeatedlyuntil [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.