CAS PW-2H User manual

PW-II Service Manual
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PW-II SERVICE MANUAL

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< Table of Contents >
1. Introduction ............................................................................................................................... 4
1.1. Preface................................................................................................................................... 4
1.2. Precaution............................................................................................................................ 4
1.3. Specifications..................................................................................................................... 5
1.3.1. PW-II Specifications ...................................................................................... 5
1.4. Key............................................................................................................................................ 6
1.5. Sealing Method ................................................................................................................. 7
2. Calibration................................................................................................................................... 8
2.1. General Calibration......................................................................................................... 8
2.1.1. C4 Setting ............................................................................................................. 9
2.1.1.1. C4-1 Setting................................................................................................. 9
2.1.1.2. C4-2 Setting................................................................................................. 9
2.1.1.3. C4-3 Setting................................................................................................. 9
2.1.1.4. C4-4 Setting................................................................................................. 9
2.1.1.5. C4-5 & 4-6 Setting................................................................................. 10
2.1.2. SPAN Calibration Setting (C-3).............................................................. 10
2.1.3. Gravity Constant Value Setting (C-9) ................................................ 11
2.1.4. Displaying Real A/D Value (C-5).......................................................... 11
2.1.5. How to confirm SPAN calibrated A/D value (C-1) ..................... 12
2.1.6. Back to the normal weighing mode (C-0)....................................... 12
2.1.7. Calibration Block Diagram........................................................................ 13
3. The Schematics and Diagram......................................................................................... 14
3.1. System Block Diagram................................................................................................ 14
3.2. Circuit Diagram............................................................................................................... 15
3.2.1. Main........................................................................................................................ 15
3.2.2. A/D ......................................................................................................................... 16
4. Exploded View......................................................................................................................... 17

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5. Part Location............................................................................................................................ 18
5.1. Main PCB (Front) ........................................................................................................... 18
5.2. Main PCB (Rear)............................................................................................................. 19
5.3. Battery PCB....................................................................................................................... 20
5.4. Key PCB ............................................................................................................................. 201
6. Partlist ......................................................................................................................................... 22
6.1. Circuit Part .................................................................................. 22
6.1.1. Main PCB Ass'y....................................................................22
6.1.2. Battery PCB Ass'y................................................................23
6.1.3. Key PCB Ass'Y………………………………………………………………23
6.2. Mechanism Part ........................................................................... 24
6.2.1. Body Ass'y...........................................................................24
6.2.2. C/T Box Ass'y......................................................................25
6.2.3. Loadcell Ass'y………………………………………………………………25
7. Error Message & Solution…………………………………………………………...26
7.1. Beep : Re-zero…...........................................................................26
7.2. Err : Initial zero…………………………………………………………………….26
7.3 Init : Failure of Analog Module……………………………………………….26
7.4 UNSTA : A/D Value Unstable………………………………………………….26

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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 PW 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
1.3.1.PW-II Specifications
PW-II(2kg) PW-II(5kg) PW-II(10kg)
Capacity / e
Low
Resolution
2,000g / 1 g
(2 kg / 0.001 kg)
5 lb / 0.002 lb
80 oz / 0.05 oz
5,000g / 2 g
(5 kg / 0.002 kg)
10 lb / 0.005 lb
160 oz / 0.1 oz
10,000g / 5 g
(10 kg / 0.005 kg)
20 lb / 0.01 lb
400 oz / 0.2 oz
High
Resolution
2,000.0g / 0.5 g
2 kg / 0.0005 kg
(1/4,000)
5 lb / 0.001 lb
(1/5,000)
80 oz / 0.02 oz
(1/4,000)
5,000.0g / 1 g
5 kg / 0.001 kg
10 lb / 0.002 lb
(1/5,000)
160 oz / 0.05 oz
(1/3,200)
10,000g / 2 g
10 kg / 0.002 kg
(1/5,000)
20 lb / 0.005 lb
400 oz / 0.1 oz
(1/4,000)
Internal
Resolution 1 / 20,000 1 / 25,000 1 / 20,000
External
Resolution 1 / 2,000 1 / 2,500 1 / 2,000
Display 91 X 39 [mm] / 3.6 X 1.5 [inch] 5 digits LCD
Symbols
(Indicators) STABLE, ZERO, TARE, g, kg, lb, oz, Low Battery HI/OK/LO, PCS
Keys ZERO, TARE, HOLD, UNIT, POWER
Functions
•Simple Weighing function
•Hold function
•Weight Unit Conversion Function (g/kg/lb/oz)
•Auto Power Off
Dimension 239(Width) ×227(Depth) ×66(Height) [mm] /
9.4(Width) ×8.9(Depth) ×2.6(Height) [inch]
Platter Size 222(Width) ×151(Depth) [mm]/
8.7(Width) ×5.9(Depth) [inch]
Weight 1.5 kg
Power 1.5V x 6 (AA size battery) or 9 V Adaptor
Op.Temperature - 10 °C ~ +40 °C
Op. Power 9V/300mA Adaptor

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1.4. Key
Key Function
HOLD To make the weight of item stable. This weight is average value.
UNIT Used to convert the unit of weight
TARE To input or cancel the tare (the weight of container).
ZERO (-O-)
[Set]
To set zero point
To do [SET] key in the SETUP mode.
POWER To turn on or off.

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1.5. 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 [HOLD] and [TARE] key.
Please simply follow below procedure to move to other mode.
(1) Calibration Mode: Pressing and holding “Calibration Switch” press [POWER]
key.
It displays “C-0” after “CAL”, and it blinks the version of scale three times.
(2) Selecting menu: press [TARE] and then [HOLD].
(3) ENTER(Setting) : [ZERO] key
MODE Function
C – 0 To go back to simple weighing mode
C – 1 To display internal value of weight
C – 2 -
C – 3 Weight Setting Mode
(“UnLoad” →[ZERO] →“Load”→[ZERO] after loading →“END” on display)
C – 4 Capacity displayed and Option Setting
C – 5 Net internal value of weight (zero value confirmed)
C – 6
C – 7
C – 8
C – 9 Gravity constant

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2.1.1.C4 Setting
2.1.1.1. C4-1 Setting
B7 B6 B5 B4 B3 B2 B1 B0
Weight
Unit
External
Resolution Display Unit TARE
0:kg
1:lb
00: Low
01: High
00:kg
01:lb
10:oz
11:g
00: (+)One Time (-) One Time
01: (+)Successive (-) One Time
10: (+)One Time (-) Successive
11: (+)Successive (-)Successive
User should input Hexa code to set C4.
User should input “weight unit”, “external resolution”, “display unit”, and “tare”.
For example, if you want to set “kg (0)” as the weight unit, “low (00)” as the external
resolution, or “(0)” as TARE you may input “00” as Hexa value.
User can set 2,000~2,500 for low external resolution or 4,000~5,000 for high external
resolution.
2.1.1.2. C4-2 Setting
Capacity Setting
UNIT
kg g lb oz C4-2 Value
2 2,000 5 80 0000 1XXX
5 5,000 10 160 0001 1XXX
10 10,000 20 400 0010 1XXX
PW-II has four different weight units, g, kg, lb, or oz as shown in shaded area. You can set
the capacity to input first 5 bits, for example, “00011” for 5 kg capacity.
Next three (3) bits represent “Interval” information. For example, if you set 5 kg interval the
Hexa value will be “0x18”.
2.1.1.3. C4-3 Setting (Function Setting)
ROM VERSION 1 (Hold) ROM Version 2 (lb)
Function Function
S-HOLD XXXX XX00
HOLD XXXX XX00 Lb XXXX XX10

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2.1.1.4. C4-4 Setting
UNIT CHANGE Comma Setting lb ROM Version Only
Buzzer Setting
ENABLE 1XXX XXXX ENABLE XXX1 XXXX
ENABLE XXXX 0XXX
DISABLE 0XXX XXXX DISABLE XXX0 XXXX
DISABLE XXXX 1XXX
C4-4 is to set to use the unit change function and the displaying unit.
2.1.1.5. C4-5 & C4-6 Setting
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 “C-0”
message.
(2) Press [TARE] to display “C-3”.
(3) Press [ZERO] key and then it displays “UnLOAd” message.
(4) Press [ZERO] key if you want to scroll it.
Ú To exit from SPAN Calibration mode press [TARE] key when “UnLOAd” or “LOAd” message is
displayed.
C4-5 C4-6
Op Amp Setting Zero Range Setting
HA17358 XXXX XXX1 2% 10% 15% 20%
OP2177 XXXX XXX0 XXXX XX01
XXXX XX00
XXXX XX10 XXXX XX11