CAS Corporation SW-1S User manual

SW-1S/1C/1W/1N Service Manual
1 12/18/08
SW-1S/1C/1W/1N
SERVICE MANUAL
(Revision 0.2 / 2008.09.30)

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< Table of Contents >
1. Introduction ............................................................................................................................... 4
1.1. Preface .................................................................................................................................... 4
1.2. Precaution............................................................................................................................. 4
1.3. Specifications...................................................................................................................... 5
1.4. Key............................................................................................................................................. 7
1.5. Dimension.............................................................................................................................. 7
1.5.1. SW-1S/1C/1N .................................................................................................................... 7
1.5.2. SW-1W............................................................................................................................... 8
1.6. Sealing Method................................................................................................................... 9
2. Calibration................................................................................................................................. 11
2.1. General Calibration........................................................................................................ 11
2.1.1. C4 Setting ........................................................................................................... 12
2.1.1.1. C4-1 Setting................................................................. 12
2.1.1.2. C4-3 Setting................................................................. 12
2.1.2. SPAN Calibration Setting (C-3).............................................................. 13
2.1.3. Gravity Constant Value Setting (C-9)................................................ 13
2.1.4. Calibration factor Setting (C-10).......................................................... 13
2.1.5. Displaying Real A/D Value (C-5).......................................................... 14
2.1.6. Model Setting Mode (C-6)......................................................................... 14
2.1.7. Percent Calibration (C-7).......................................................................... 15
2.1.8. Battery Calibration (C-8)........................................................................... 15
3. The Schematics and Diagram......................................................................................... 16
3.1. System Block Diagram................................................................................................. 16
3.2. Circuit Diagram ................................................................................................................ 16
3.2.1. Main PCB.............................................................................................................. 16
3.2.2. Rear Display PCB............................................................................................ 19
4. Exploded View......................................................................................................................... 20
4.1. SW-1S/1C.................................................................................................................................. 20
4.2. SW-1W...................................................................................................................................... 21
5. Load Cell drawing.................................................................................................................. 22
6. Part Location............................................................................................................................ 23
6.1. Main PCB (Top) ................................................................................................................ 23
6.2. Main PCB (Bottom) ........................................................................................................ 24
6.3. Rear Display PCB (Top)............................................................................................... 25
7. Error Messages & Solution............................................................................................... 26

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8. Part List....................................................................................................................................... 27
8.1.1 SW-1S/1C/1W (Electronic part)............................................................................................. 27
8.1.2 SW-1S/1C (Mechanical part).................................................................................................. 32
8.1.3 SW-1W (Mechanical part)...................................................................................................... 35

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1. Introduction
1.1. Preface
Thank you for purchasing of our CAS scale.
This scale has been designed with CAS reliability, under rigid quality control
and with outstanding performance.
WE hope that your departments enjoy with high quality of CAS product.
This manual will help you with proper operations and care of the SW-1S/1C/1W series.
Please keep it handy for the future references.
1.2. Precaution
•Make sure that you plug your scale into the proper power outlet.
•Place the scale on a flat and stable surface.
•Plug into a power outlet 30 minutes before operations.
•Keep the scale away from strong EMI noises may cause incorrect weight readings.
•This scale must be installed in a dry and liquid free environment.
•Do not subject the scale to sudden temperature changes.
•Do not subject the platter to sudden shocks.
•If the scale is not properly level, please adjust the 4 legs at the bottom of the
scale (turn legs clockwise or counterclockwise) so as to center the bubble of the
leveling gauge inside the indicated circle.

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1.3. Specifications
MODEL PW-II/2N
Capacity /
e
2kg, e = 1g
5lb, e = 0.002lb
80oz, e = 0.05oz
5kg, e = 2g
10lb, e = 0.005lb
160oz, e = 0.1oz
10kg,e = 5g
20lb,e=0.01lb
400oz,e= 0.2oz
PW-2N only
Dec.
oz 80oz, e=0.05oz 160oz, e=0.1oz 400oz, e= 0.2oz
Frac
t. oz 80oz, e=1/16oz 160oz, e=1/8 400oz, e=1/4oz
Resolutio
n 1/2000 1/2500 1/2000
MAX Tare -2kg -5lb
-80oz
-5kg
-10lb
-160oz
-10kg
-20lb
-400oz
Display 91 x 39 [mm] / 3.6 x 1.5 [inch] 5 digits LCD (9 digit LCD, PW-2N only)
Symbols STABLE, ZERO, TARE, g, kg, lb, oz, Low Battery
Keys ZERO, TARE, UNIT, POWER
Functions Weighing, Unit Conversion(Unit Ver.),
Dimensio
ns 239(W) x 227(D) x 66(H) [mm] / 9.4(W) x 8.9(D) x 2.6(H) [inch]
Platter
size 222(W) x 151(D) [mm] / 8.7(W) x 5.9(D) [inch]
Weight 1.5kg / 3.3lb
Power 1.5V x 6 units (AA size Battery) or 9VAdapter
Operation
Time Approx. 60hours (Manganese battery)/ 250hours (Alkaline at 20°C /68°F)
Operating
Temperat
ure -10°C ~ +40°C / 14°F ~ 104°F
Minimum
Voltage
Level of
The
Battery
About 5.5V

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Option 9VAdapter 300mA

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1.4. Key
Key Function
ZERO (-O-)
[Set]
To set zero point
To do [SET] key in the SETUP mode.
TARE To input or cancel the tare (the weight of container).
UNIT Used to convert the unit of weight.
POWER To turn on or off.
1.5. Dimension
1.5.1. SW-1S/1C/1N

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1.5.2. SW-1W

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1.6. Sealing Method

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2. Calibration
2.1. General Calibration
Pressing and holding calibration switch press [POWER] key to go to calibration mode.
User can move to other mode by using [ZERO] key in the calibration mode.
User also moves to other sub-modes for each mode by using [TARE] key.
Please simply follow below procedure to move to other mode.
(1) Calibration Mode: Pressing and holding “Calibration Switch” press [POWER] key.
(2) It displays “CAL-0” after “CAL”, and it blinks the version of scale three times.
(3) Selecting menu: press [TARE].
(4) ENTER(Setting) : [TARE] key
MODE Function
CAL 1 Display normalized AD
CAL 2 Display Keypad infomation-
CAL 3
Weight Setting Mode
“UnLoad”  [TARE] 
“MIDD”  [TARE] after loading for 1/3 weight 
“FULL”  [TARE] after loading for Full weight 
“MIDD”  [TARE] after loading for 1/3 weight  “END”
CAL 4 Option Setting ( Refer to Table 1)
CAL 5 Display filtered Raw AD
CAL 6 Model Setting Mode
CAL 7 % Calibration
CAL 8 Battery calibration
CAL 9 Gravity constant
CAL 10
Set calibration factor
“Unit” Æ[TARE] Æselect 0, 1 (0:kg, 1: lb) Æ[TARE]
“CAPA” Æ[TARE] Æselect capacity Æ[TARE]
“MCAPA” Æ[TARE] Æselect mid-capacity Æ[TARE]
“W-dP” Æ[TARE] ÆSelect Decimal Point Æ[TARE]
“ 1 d ” Æ[TARE] ÆSelect division Æ[TARE]
“Dual” Æ[TARE] ÆEnable dual interval (0:disable, 1:enable) Æ[TARE]
“tare” Æ[TARE] ÆEnable custom tare (0:disable, 1:enable) Æ[TARE]
CAL 11 Set nation(00 : OIML , 01 : NTEP , 02: KOREA)

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< Modes >
2.1.1. C4 Setting
2.1.1.1. C4-1 Setting
BIT 6~7 Initial Zero range
3 5%
2 10%
1 3%
0 2%
BIT5 Last digit enable 0 Disable
1 Enable
BIT4 Key zero percent 0 ±3% key zero percent
1 ±2% key zero percent
BIT 2~3 Successive tare
3 (+), (-) All Direction successive Tare
2 (+) Direction successive Tare
1 (-) Direction successive Tare
0 One Time tare
BIT0~1 Zero mark type
0 Gross zero indication
1 Net zero indication
2 Both(gross and net) zero indication
2.1.1.2. C4-3 Setting
BIT7 Dot Type
0 "." dot
1 "," comma
BIT6 Use Preset tare 0 Don't use
1 Use
BIT5 Use Back light 0 Don't use
1 Use
BIT4 Use Head message 0 Don't use
1 Use
BIT3 Use gram
0 Don't use
1 Use
BIT2 Use oz
0 Don't use
1 Use
BIT1 Use lb
0 Don't use
1 Use
BIT0 Use Kg
0 Don't use
1 Use

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2.1.2. SPAN Calibration Setting (C-3)
(1) Pressing and holding “Calibration Switch” press [POWER] key.
After “CAL” message blinks three times and shows the version of scale, it displays “CAL
1” message.
(2) Press [ZERO] to display “CAL-3”.
(3) Press [TARE] key and then it displays “zero ” message.
(4) Press [TARE] key and then it displays “midup” message
(5) Load middle weight (ex:1/3 full capacity) on the platform
(6) Press [TARE] key and then it displays “span ” message
(7) Load full weight on the platform
(8) Press [TARE] key and then it displays “middn” message
(9) Load middle weight (ex:1/3 full capacity) on the platform
(10) Press [TARE] key and then it display “CAL 3” message
2.1.3. Gravity Constant Value Setting (C-9)
Current gravitational Acceleration value is set to 9.7994 m/s2 .
(11) Pressing and holding “Calibration Switch” press [POWER] key.
After “CAL” message blinks three times and shows the version of scale, it displays
“CAL-1” message.
(12) Press [ZERO] to display “C-9”.
(13) Press [TARE] key, and then “ G-1“ message and “9.7994” will be shown. The first
digit,”9” will blink.
(14) Input a gravitational acceleration value by using [ZERO] key.
(15) Press [TARE] key, and then “G-2“ message blinks.“9.7994” will be shown. The first
digit,”9” will blink.
(16) Input a gravitational acceleration value by using [ZERO] key.
(17) Press [TARE] key to save the gravitational acceleration value, and “C-9 ” message
will be shown.
2.1.4. Calibration factor Setting (C-10)
(1) Pressing and holding “Calibration Switch” press [POWER] key.
(2) After “CAL” message blinks three times and shows the version of scale, it displays
“CAL-1” message.
(3) Press [ZERO] to display “C-10”.
(4) Press [TARE] key, and then “UNIT “ message and “0” will be shown. The first digit,”0”
will blink. It means calibration unit is “kg” (0 : kg, 1 : lb)
(5) Input a calibration unit by using [ZERO] key.
(6) Press [TARE] key, and then “CAPA“ message blinks.“0015” will be shown. The first
digit,”0” will blink. It means a full-capability is “15 (calibration unit, kg or lb)”

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(7) Input a capability by using [ZERO] key.
(8) Press [TARE] key, and then “MCAPA“ message blinks.“0005” will be shown. The first
digit,”0” will blink. It means a mid-capability is “05 (calibration unit, kg or lb)”
(9) Input a capability by using [ZERO] key.
(10)Press [TARE] key, and then “W-dP “ message blinks.“3” will be shown. The first
digit,”3” will blink. It means a weight decimal point is “3 (will display 0.000)”
(11)Input a weight decimal point by using [ZERO] key.
(12) Press [TARE] key, and then “1d “ message blinks.“0.005” will be shown. The third
digit,”0” will blink. It means a division is “0.005 (calibration unit, kg or lb)”
(13) Input a division by using [ZERO] key.
(14) Press [TARE] key, and then “dual “ message blinks.“1” will be shown. The third
digit,”1” will blink. It means a dual interval is disable. (0 : disable, 1 : enable)”
(15) Input a dual interval enable by using [ZERO] key.
(16) Press [TARE] key to save the calibration factor, and “C-10 ” message will be shown.
2.1.5. Displaying Real A/D Value (C-5)
Display Raw AD
2.1.6. Model Setting Mode (C-6)
(1) Get into the C-6 setting.
(2) There will be 3 setting value which are "S" , "C", & "U"
(3) You can switch these 3 value by push the Unit key and Tare key at the same time. Each
value will be changed to other value step by step by pushing the Unit key and the Tare key
at the same time.
(4) Set the value "U" and push zero key in order to save "U" setting value.
(5) Turn off the scale and turn on the scale again.
(6) The unit conversion function will be enabled.

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2.1.7. Percent Calibration (C-7)
(1) Pressing and holding “Calibration Switch” press [POWER] key.
After “CAL” message blinks three times and shows the version of scale, it displays “CAL 1”
message.
(2) Press [ZERO] to display “CAL-7”.
(3) Press [TARE] key and then it displays “per 0 ” message. Select the percent value using
the
[numeric] key. You can choose 10~90 percent. (Last digit of percent must be 0.)
(4) Press [TARE] key and then it displays “zero” message
(5) Press [TARE] key and then it displays “pspan ” message
(6) Load choice percentage weight of full weight on the platform
(7) Press [TARE] key and then it displays “CAL 7” message
2.1.8. Battery Calibration (C-8)
(1) Pressing and holding “Calibration Switch” press [POWER] key.
After “CAL” message blinks three times and shows the version of scale, it displays “CAL 1”
message.
(2) Press [ZERO] to display “CAL-8”.
(3) Press [TARE] key and then it displays voltage of battery.
(4) Change the jumper-pin of main PCB, ‘BAT’ to ‘+5V’.
(5) Press [ZERO] key two times and then Press [-] key two times.
And then it display ‘500’
(6) Change the jumper-pin of main PCB, ‘+5V’ to ‘BAT’.
(7) You can see the calibrated voltage of battery.

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3. The Schematics and Diagram
3.1. System Block Diagram
3.2. Circuit Diagram
3.2.1. Main

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PCB

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3.2.2. Rear Display PCB

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4. Exploded View
4.1. SW-1S/1C/1N