TScale M503 Series User manual

I
Weighing Indicator
M503
Wheelchair Scale

M503 Series Wheelchair Scales Technical Manual
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CONTENTS
1. PRECAUTIONS……………………………………………………………..2
2. INTRODUCTION……………………………………………………………3
3. SPECIFICATIONS……………………………………………………….....4
3.1Specifications………………………………………………………………...4
3.2 Load Cell Specification...............................................................…...5
4. INSTALLATION……….…………………………………………………….6
5. DESCRIPTION……….....................................................................8
6. OPERATION………………………………………………………………..10
1. Power ON/OFF…………………………………………………………10
2. Zero……………………………………………………………………...10
3. Tare……………………………………………………………………...10
4. Hold function…………………………………………………………....10
5. BMI function…………………………………………………………….11
7. PARAMETER……………………………………………………………….12
8. CALIBRATION……………………………………………………………..14
9. BATTERY OPERATION…………………………………………………..15
10.MAINTENANCE……………………………………………………………16
10.1 General………………………………………………………………..16
10.2 Error codes……………………………………………………………17
10.3 Determine the Problem……………………………………………...17
10.4 Check the Load Cell…………………………………………………17
10.5 Check PCB Voltages………………………………………………...18
10.6 Trouble Shooting……………………………………………………..19
11.DISPOSAL……………………………………………………………………20
12.WARRANTY……………………………………………………………………21

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1. PRECAUTIONS
WARNING
DISCONNECT ALL POWER TO THIS UNIT
BEFORE INSTALLING, CLEANING, OR
SERVICING. FAILURE TO DO SO COULD
RESULT IN BODILY HARM OR DAMAGE THE
UNIT.
CAUTION
Permit only qualified persons to service the instrument
Before connecting or disconnecting any components, remove the
power.
Failure to observe these precautions bodily harm or damage to or
destruction of the equipment.
Follow the instructions in the instructions for use.
Keep the operating instructions and the declaration of
conformity in a safe place.
Never leave the old man seat on the scale unsupervised.
Ensure that the scale is standing firmly on a smooth, level
surface.
Do not drop the scale or subject it to violent shocks.
When using the scale with a mains unit, ensure that the
supply cable is routed in such a way as to exclude any type
of tripping hazard.
Use only the type of battery stated.
Have scale serviced and re-calibrated on a regular basis.
Have repairs carried out only by authorized persons.

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2. INTRODUCTION
The M503 series wheelchair scales, that amplifies signals from a load cell,
converts it to digital data and displays it as a mass value.
It is accurate, fast and versatile series of general purpose balances with %
weighing functions and accumulation.
All models with ECTAC(Class III) and conform 93/42/EC directive.
Materials used according to REACH directive.
Safe and comfortable wheelchair weighing scales
Users can choose to put the meter location by themselves
Ramp foldable, when folded out with low distance to the floor.
Optional RS-232 interface, can connect computer and printer.

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3. SPECIFICATION
3.1 Specifications
Model
M503-300k
Maximum Capacity
300kg/660lb
Readability
0.1kg/0.2lb
Resolution
1/3,000
Tare range
-249.9kg
Minimum Capacity
2kg/4lb
Linearity ±
0.2kg/0.4lb
Common Specifications
Interface
RS-232 Output Optional
Stabilisation Time
2 Seconds typical
Operating Temperature
0°C - 40°C / 32°F - 104°F
Power supply (external)
12V/500mA AC power adapter or 2000mAh Ni-MH
batteries (optional, size AA)
Calibration
Automatic External
Calibration as per Directive
90/384/EEC
Class III medical approval
Medical product as per
Directive 93/42/EEC
Class I
ADC
Σ-Δ
Display
25 mm high 6 digits LCD with auto backlight and
loading bar graph
Housing
Aluminium platform, ABS plastic indicator
Gross weight
85kg

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3.2 Load Cell Specifications
Model No
L6E3
Rated Capacity (kg)
2.5/3/5/6/8/10/15/20/30/35/40/50
Sensitivity
2.0±0.2 mv/v
Excitation Voltage
5~12V
Material
Aluminum
Cable
0.3~3m Φ 4mm
Input Resistance
409Ω ±6Ω/1065Ω ±15Ω
Out put Resistance
350Ω ±3Ω/1000Ω ±10Ω
Temperature Range
-35°C ~ +65°C
Safe overload
150%F.S
Ultimate overload
300%F.S
Error
±0.0233%F.S
Creep (20min)
±0.020%F.S
Zero Balance
0±5%mV/V
Max. Platform Size
250x350mm

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4. INSTALLATION
Unpacking
Carefully take the balance out of its package, make it sure its not damaged and
all accessories are included.
Remove the weighing scale from the carton.
Remove the protective covering. Store the packaging and to use if you
need to transport the scale later.
Inspect the scale and terminal for damage.
Make sure all components are included
Accessories,
1. Balance
2. Adaptor
3. Product manual
Level Adjusting
Place the scale on a table.
Check the water mark. If, bubble is not centre
adjust the leveling feet until reach centre. Check
the level when you change the location.
Charging Battery
To charge the battery insert the adaptor pin to jack, jack is locating rear side
of the scale. Adaptor simply plug into the mains power. The scale no
needs to be turned on.
The battery should be charged for 12 hours for full capacity.
In the display there is an indicator show the status of battery charging.
When the scale is plugged into the mains power the internal battery will be
recharged. If the indicator off, the battery has a full charge. If it is on, the
battery is nearly discharged and if yellow, the battery is being charged.
Do not use any other type of power adaptor than the one supplied with the
scale.
Verify that the AC power socket outlet is properly protected.
Note: Please charge the battery before using the scale for the first time

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Installation
Load cell Connecter
Adaptor Jack
Calibration switch
Place the scale on a table.
Connect the adaptor pin in to the scale adaptor jack. Adaptor jack is
locating, rear side of the scale.
Adaptor connects into your AC power socket.
Pluggable equipment must be installed near
an easily accessible socket outlet with a
protective ground/ earth contact.
Display will be show the version number and will
be starting self checking.
After self checking, display will be come to normal weighing mode.
Warm-up time of 15 minutes stabilizes the measured values after
switching on.
Calibrate with exact calibration weights, minimum 1/3 of the scale capacity
want to use for calibration. For calibration see details in parameter.
Then you can start your operation

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5. DESCRIPTION
Key Board
Turns the scale power On / Off
Set to hold mode
Set to BMI mode
Enter into the menu
Sets display to Zero
Subtracts weight of container
Change unit: kg / lb

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Display
DISPLAY
FUNCTION
STABLE
Indicator for Display stability
ZERO
Indicator for Zero display
TARE
Indicator for Tare display
NET
Indicator for Net weight
GROSS
Indicator for Gross weight
Cm/inch
Indicator for measuring units
Lb/kg
Indicator for weight units
Indicator for Charging status of battery
Voltage has dropped
Low Voltage
Fully Charged

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6. OPERATION
Initial Start-up
Warm-up time of 15 minutes stabilizes the measured values after switching on.
6.1 Power ON/OFF
Switch on the scale by pressing . The display is switched on and the
self test is started.
If you want to switch off press the key again.
6.2 Zero
Environmental conditions can lead to the balance exactly zero in spite
of the pan not taking any strain. However, you can set the display of
your balance to zero any time by pressing key and therefore
ensure that the weighing starts at zero.
6.3 Tare
The weight of any container can be tared by pressing key so that
with subsequent weighing the net weight of the object being weighed is
always displayed.
Load weight on the pan.
Press key. Zero is displayed, and tare is subtracted.
Remove weight from the platform. Tared weight is displayed. It can
set only one tare value. It can display with a minus value.
Press key. Zero is displayed, tare weight is cleared.
6.4 Change unit
In weighing condition, you can press to change the unit: kg / lb.
If you want to change the unit of height measurement, please set it in
parameter F5 stu. (page 13)

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6.4 Precision*10
If you want to see more accurate weight value, press and hold for 2
seconds, display will show one more decimal place, the last digit will twink for 5
seconds, then it will go back to normal weighing value automatically.
6.5 BMI function
Press key on the weighing mode, display will show the last height “xxxxxx”,
use key turn last digit, and press key to increase the value, press
key confirm it, display will enter into the BMI mode, “BMI”indicator will be show,
people stand on the platform display will show the BMI graphics bar and BMI
value.
Press key，it will turn back to weighing mode.
6.6 Hold function
Press before load at the pan, so HOLD is active now. "Hold " and "---
--" appeared at the display.
After put load at the pan no indication until a stable non-zero weights is
detected. During this period "----" is indicated. (no indication of unstable
value).You will hear an acoustic beep, when stable weight (>20d)is detected.
It will show calculated HOLD-value with small "HOLD" in display.
After unloading the pan the value is indicated for 10 Seconds. After that
normal weight displaying is resumed.
Pressing , while the HOLD-function is active, will cancel the HOLD-
function.
In hold function, you can’t do ZERO and TARE operation.

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7. PARAMETERS
Enter the Menu
Turn on the scale. Press key display will show
Choose the Menu
Press , it can choose menu block or options one by one.
Enter the Selected Menu
Press , it can confirm which will be shown displayed.
Enter in to TECH
Note: Before enter the tech menu, press calibration switch, which is
locating below the scale
When display showed Pi n , press and keys to enter
the function
Escape from the Menu
Press key, it can escape from the menu to weighing mode.
Parameter Block
Menu
Sub
Menu
Description
F1 off
Off
0/3/5/15/30
To set the auto close the scale time.
F2 com
Select first RS 232 or USB
P prt
By pressing Print key , weighing value will be
added to the memory and print the print out
P cont
Send data continuous
P auto
Automatic accumulation.
Individual weighing values are automatically
F1 off

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added
P ask
ASK mode
Command R: read data
Command T: Tare
Command Z: Zero
Wirele
Wireless (optional)
P cnt2
Send data another continuous mode.
F3 bk
Bl on
Set the backlight always on.
Bl off
Set the backlight always off.
Bl au
Set the backlight automatic on.
F4 str
Str on
Multi tare operation turn on
Str off
Multi tare operation turn off
tch
pin
Enter the password
P 1 spd
Set the display speed(7.5/15/30/60)
P 2 Cal
Normal Calibration
P 3 pro
tri
To modify the calibration.
count
To show the scale internal count
reset
Reset the scale
setgra
Set the gravity value

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8. CALIBRATION
Turn on the scale.
Press key during normal weighing, display will show “f1 off”
Press key until display will show “tech”
Press key to confirm display will show “PIN ”
Press and keys, display will show “p1 spd”
Press key ，display show ”p2 cal”
press key, Display will show “desc”, press key several times
until display show ”cal”, press key into calibration, display will show
“UNLOAD”,
When scale get stable, Press key, display will show the calibration
value, you can change the value by pressing and key, then
press
key to comfirm.
display will show “load”
Place the calibration weight on the platform, press key after stable,
display will show “pass”.
Calibration will be finished, scale will start self test.
After three times, scale will be calibrate automatically and will start self test.
Note: Incase display will show any error message or incorrect measurement,
repeat the calibration again.

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9. BATTERY OPERATION
The Medical Scales can be operated from the battery if desired. The battery life
is approximately 70 hours.
When the battery needs charging a symbol on the weight display will turn on. The
battery should be charged when the symbol is on. The scale will still operate for
about several minutes after which it will automatically switch off to protect the
battery.
To charge the battery simply plug into the mains power. The scale does not need
to be turned on.
The battery should be charged for 12 hours for full capacity.
Just under the quantity display is an LED to indicate the status of battery
charging. When the scale is plugged into the mains power the internal battery
will be charged. If the LED is green the battery has a full charge. If it is Red the
battery is nearly discharged and yellow indicates the battery is being charged.
As the battery is used it may fail to hold a full charge. If the battery life becomes
unacceptable then contact your distributor.
Note: useless battery should be recycled, not throw away as household refuse.

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10. MAINTENENCE
WARNING
DISCONNECT ALL POWER TO THIS UNIT
BEFORE INSTALLING, CLEANING, OR
SERVICING. FAILURE TO DO SO COULD
RESULT IN BODILY HARM OR DAMAGE THE
UNIT.
CAUTION
Permit only qualified persons to service the instrument
Before connecting or disconnecting any components, remove the
power.
Failure to observe these precautions bodily harm or damage to or
destruction of the equipment.
10.1. 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

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Cleaning
Disconnect the power before cleaning.
Use a cloth with mild suds and light cleaning agents.
Make sure that fluid not able to get into the device.
Use a clean and soft cloth for rub off.
10.2. Error Codes
Error Code
Description
POSSIBLE CAUSES
Err 4
Exceed manual zero range
(pressing )
Goods on the platform
Overload, when
zeroing the scale.
Improper calibration
Load cell problem
PCB problem
Err 6
A/D Count out of the range
Platform not installed
Load cell problem
PCB problem
Err 19
Exceed Auto Zero range
When switch on the scale
Goods on the platform
Improper calibration
Load cell problem
PCB problem
10.3. Determine the Problem
Determine whether the problem is in the PCB or the Load Cell
Remove power from the system, and disconnect the load cell connection
from the PCB
Connect the PCB to a load cell simulator
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

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10.4. Check the Load cell
Remove power from the system, and disconnect the PCB from the Load
cell
Check the moisture, or foreign material inside.
Make sure all leads are connected and correctly.
Check load cell for proper input and output resistances
Load Cell Connections
Signal + Green
Supply + Red
Signal - Black
Supply - White
Shield
Measuring Points
Resistance
Red (+ Exc) to White ( –Exc)
420 ±20Ω
Green (+Sig) to Black ( –Sig)
350Ω ±5Ω
10.5. Check PCB Voltages
If the problem is in the PCB, use a multimeter to check the following voltages
10.5.1 AC Power
Check the AC power socket out put voltage.
Voltage must be a -20% and +10% of the normal AC voltage.
10.5.2 Adaptor Voltage
Check the adaptor output cable connecter voltage
Voltage must be minimum 9VDC and maximum 15VDC

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10.5.3 PCB Input Voltage
Check the PCB input power connecter voltage
Voltage must be minimum 9VDC in to the pin AD+
10.5.4 Check Battery Voltage and Charging Voltage
1. Check the Battery Voltage,
Voltage must be minimum 6VDC. If below the 6VDC connect the adaptor
for charging
The battery voltage below the 5.5VDC, replace the battery and install new
6V/3.4Ah battery.
2. Check the Battery Charging Voltage;
Remove the battery connection terminals (Red and Black) from the battery.
Connect the power and turn on the scale
Voltage into the terminal minimum 6.5VDC
10.6 Trouble Shooting
Problems
Possible cause
Common Solutions
Display is blank.
No self test
Mains power is turned
off. Power supply faulty
or not plugged. Internal
battery is not charged.
On/Off switch problem
Check power is getting inside the
scale and on/off switch is working.
Verify the voltages, which is on the
power labels.
Blank display
after self test
Pan not installed.
Unstable weight, load
cell damaged
Check the pans are installed
correctly. Try to turning on again.
OL or -------
Maximum capacity
exceeded. Load cell or
mechanics damaged.
Power supply faulty
Check the platform is installed
correctly. Try to turn on the scale
again. Do the calibration again
------- or NULL
displayed
Weight is on the
platform is below
permissible limit. Pan
not installed correctly.
Power supply faulty.
Load cell or
mechanism faulty
Check the platform is installed
correctly. Try to turn on the scale
again.
Do the calibration again