Avery Weigh-Tronix PC-905 User manual

43003-0015A e2 3.07.2006
*43003-0015*
PC-905 Counting Scale
PC-905
Service Manual
ENGLISH - USA

©Avery Weigh-Tronix LLC, 2005. All rights reserved.
The information contained herein is the property of Weigh-Tronix, Inc and is supplied without liability for
errors or omissions. No part may be reproduced or used except as authorized by contract or other written
permission. The copyright and the foregoing restriction on reproduction and use extend to all media in
which the information may be embodied.
Avery Weigh-Tronix is a trading name of Weigh-Tronix, Inc
Trademarks and acknowledgements
Avery Weigh-Tronix, Avery Berkel, Dillon, NCI and Salter Brecknell are registered trademarks in certain
jurisdictions.
All third party brands and product names used within this document are trademarks or registered
trademarks of their respective holders.
IMPORTANT
When programming or configuring the equipment you must ensure that you comply with all relevant
standards and legislation. The example settings given in this book may not be legal for trade with the
public.
Declarations of compliance
United States
This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15
of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the
equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful
interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful
interference in which case the user will be required to correct the interference at his own expense.
Canada
This digital apparatus does not exceed the Class A limits for radio noise emissions from digital apparatus set out in
the Radio Interference Regulations of the Canadian Department of Communications.
Le présent appareil numérique n’émet pas de bruits radioélectriques dépassant les limites applicables aux appareils
numériques de la Classe A prescrites dans le Règlement sur le brouillage radioélectrique edicté par le ministère des
Communications du Canada.

PC-905 Counting Scale Service Manual 3
page
Contents.........................................................................................................................3
Introduction.....................................................................................................................5
Keyboard and Display .............................................................................................5
Battery power option ................................................................................................8
Internal battery ...................................................................................................8
External battery..................................................................................................8
Accessing the Menu.................................................................................................9
Using the Menu ............................................................................................................11
COUNT Menu.........................................................................................................13
CONFIGURATION Menu .......................................................................................15
CALIBRATION Menu .............................................................................................16
Calibrating the Local Base .....................................................................................17
Calibrating a Remote Base ....................................................................................19
SCALE Menu..........................................................................................................21
SERIAL Menu.........................................................................................................23
DIAGNOSTICS Menu.............................................................................................25
AGENCY Menu ...................................................................................................... 27
DIAGNOSTICS 911 Menu......................................................................................29
Error Messages............................................................................................................31
Communications...........................................................................................................32
Cable Pinouts ........................................................................................................32
Preset Print Formats ..............................................................................................34
Imp Printer Formats..........................................................................................34
Dymo Label Writer Setra 300 Formats.............................................................37
Zebra 2844 Printer Formats.............................................................................38
PC Protocol......................................................................................................39
NCI Protocol.....................................................................................................41
Broadcast Protocol...........................................................................................43
Disassembly and Reassembly Instructions..................................................................44
Removing the Weight Sensor...........................................................................45
Removing the Optional Remote Scale Card ....................................................46
Removing the Main PC Board..........................................................................47
Technical Illustrations...................................................................................................49
Contents

4PC-905 Counting Scale Service Manual

5
This manual contains the information you need to configure, calibrate and
service the PC-905 counting scale. This section of the manual is divided into
the following areas:
•1.1 - Keyboard and Display (page 5)
•1.2 - Battery power option (page 8)
•1.3 - Accessing the Menu (page 9)
•
1.1 Keyboard and Display
Figure 1.1 shows the front panel of the PC-905. This is made up of the
keyboard and display.
Figure 1.1 PC-905 Front Panel
The numeric keypad on the right side of the front panel has two function
keys:
•CLEAR Lets you clear the displayed number, tare, or
piece weight. Press to clear the last display digit
during digit entry.
If you press the RCL/. key followed
by a numeric key, the PC-905
treats the first key press as a
decimal and not a recall request.
•RCL/. Use this to recall the last tare, piece weight,
sample size or to enter a decimal (only if a
numeric key is pressed first).
Use the 0-9 numeric keypad for entering piece weight or tare values.
Introduction
1

6PC-905 Counting Scale Service Manual
Introduction
There are five keys below the display:
•COUNT/WEIGHT Toggles between displaying weight and count
when a piece weight is active. Acts as an escape
or up key while in the menu mode.
•PRINT Press this key to send serial data from the RS-
232 port to a connected printer. If the unit is
configured for PC or Broadcast mode, this key
will not function. See the Service Manual. Press
and hold to access the menu mode.
•UNITS Press this key to change the displayed unit of
measure. If enabled, the choices are lb, kg, g,
and oz.
•PIECE WEIGHT Lets you key in a known piece weight. Press this
key after entering a numeric value to accept it as
the current piece weight and make the count
mode active.
•BASE Toggles between the local and remote base. You
must have this option installed and a remote base
connected for this to function. Display will show
CAn’t if option not installed and the key is
pressed.
There are three keys to the right of the display:
•SAMPLE Used to select a sample size and to initiate the
calculation of sample piece weight.
This key also functions as an ON/STANDBY key
for battery powered scales. Press the key to start
the scale. Press and hold this key for five
seconds to put the scale in STANDBY mode. The
display will show SLEEP.
As long as AC is connected to the scale it will
power up where it left off unless the scale is
sealed. When sealed it performs the full power up
count down and zero reset.
Press this key to move to the right in the menu.
•TARE Press this key to tare the weight on the scale.
You can also press this after keying in a numeric
tare value to accept it and activate net weight
mode.
Press this key to move left in the menu.
•ZERO Zeroes the scale weight or count.
Press this key to accept displayed items in the
menu.

PC-905 Counting Scale Service Manual 7
The display has seven alphanumeric characters for displaying numbers and
messages. Annunciators are built into the display to indicate the following
functions:
•COUNT Annunciator indicates the scale is in count mode.
•WEIGHT Annunciator indicates scale is in weight mode.
• lb, kg, g, oz Annunciator indicates the current unit of
measure.
• LOCAL Annunciator indicates the local scale is active
•REMOTE Annunciator indicates the remote scale is active.
•LO BAT Annunciator indicates the battery has 1 or 2 hours
of battery life remaining, depending on battery
installed. See the battery information under 1.2 -
Battery power option (page 8). Recharge the
battery when this is displayed.
• STABLE Annunciator indicates weight on the scale is
stable based on the setting in the SCALE menu.
• TARE Annunciator indicates a tare weight is in effect
and displayed weight is net weight.
•ZERO Annunciator indicates the scale is at center zero
weight.

8PC-905 Counting Scale Service Manual
Introduction
1.2 Battery power option
The PC-905 has an internal and an external battery option.
The battery can be recharged in place by connecting the transformer to a
power source and to the scale. The battery will recharge while the scale is
being powered by the transformer. See the Battery Information table below
for information on charge times, etc. The battery circuits are designed with
overcharge protection.
Press the SAMPLE key on the front panel to turn the scale on. Press the
SAMPLE key for five seconds toput the scalein Standbymode. You canset
the battery option to shutoff the scale automatically after a period of time.
See IDLE time setting under the Config menu item.
Internal battery If you ordered the internal battery, it will be installed in the unit prior to
shipping. Connect to AC power and charge the battery for 16 hours prior to
first use of the scale.
External battery If you are going to use the external battery, remove the transformer from
beneath the scale, place the battery in its place with padding between the
battery and the scale base and around the battery. Secure the battery with
the restraining strap. Plug the battery cable into the receptacle on the back
of the scale. See the technical illustrations in the back of this manual for
detailed drawings of battery installation.
Risk of explosion if battery is replaced with an
incorrect type. Observe polarity when replacing
battery
Used batteries must be recycled or disposed of
properly.

PC-905 Counting Scale Service Manual 9
1.3 Accessing the Menu
1.3 Accessing the Menu
The menu for setting up the scale operation is accessed in one of two ways:
1. Press and hold the PRINT key for five seconds for available menu
items.
The display will indicate the ACCESS setting, no ACC, SUPr or
SErv, (see below for explanations) and then show the AUDIT trail
counters.
ACCESS:
The menu items available to you depend on the access granted in
the AGENCY menu. See Figure 2.11 - AGENCY Menu (page 27).
If Access is set to NO ACCESS, the unit will return to normal
weighing operation.
If Access is set to SUPV, these menu items are unavailable:
CALIB, SCALE and the 911 Diagnostics menu.
If Access is set to SERV, full access is granted.
AUDIT counters:
If there is no remote option installed you will see the following in the
order shown. XXX is the number of times the unit has been
configured or calibrated.
ConFig then XXX
CALib then XXX
Then the unit enters the menu and Count is displayed.
If there is a remote option installed you will see the following in the
order shown. XXX is the number of times the unit has been
configured or calibrated. Lstands for local base and r for the
remote base.
ConF L then XXX
ConF r then XXX
CALib L then XXX
CALib r then XXX
Then the unit enters the menu and Count is displayed.
2. For full menu access, no matter what the status of the Access menu,
press the menu access button shown in Figure 1.2. To find this button,
remove the scale shroud and seal plate. Do not unseal the scale
unless you are absolutely sure. This may require recertification of
the scale by your local weights and measures organization.

10 PC-905 Counting Scale Service Manual
Introduction
Figure 1.2 Menu access button location

11
Because a 7 segment display
cannot show all of the alphabet, the
words on the display are the
closest representations that can be
accomplished of the words they
represent. The menus show the
words as you will see them on the
display. In text, the words are all
upper case, bold and italic.
Access the menu structure by following the steps in the previous section.
The top level of the menu is shown in Figure 2.1 and includes these items:
•2.1 - COUNT Menu (page 13)
•2.2 - CONFIGURATION Menu (page 15)
•2.3 - CALIBRATION Menu (page 16)
•2.6 - SCALE Menu (page 21)
•2.7 - SERIAL Menu (page 23)
•2.8 - DIAGNOSTICS Menu (page 25)
•2.9 - AGENCY Menu (page 27)
•2.10 - DIAGNOSTICS 911 Menu (page 29)
Figure 2.1 Top level menu structure
The full menu is shown on the next page in Figure 2.2. Follow the legend at
the top of the menu to navigate through the menu. Each toplevel menu item
is explained in detail in the following pages, in the same order as the items
appear in the menu.
There is a special diagnostic menu for emergency use that is available if you
have full menu access. This is the 911 Diagnostics menu. Accessing this
menu and what it covers can be found in DIAGNOSTICS 911 Menu on page
29
Using the Menu 2

12 PC-905 Counting Scale Service Manual
Using the Menu
Figure 2.2 Service Menu

PC-905 Counting Scale Service Manual 13
2.1 COUNT Menu
2.1 COUNT Menu
The count menu, shown in Figure 2.3, allows you to set up the counting
functions of the scale.
Figure 2.3 COUNT menu
The items in the count menu are:
Choices in bold denote default
settings. Spl Lo Stands for Sample Low. Use this to choose the minimum allowable sample size when you press the SAMPLE key.
Choices: SPL-1, SPL-2, SPL-5, SPL-10, SPL-25, SPL-50,
SPL-100
Example:Ifyoupick SPL-5,Add 5 isdisplayedas theminimum
sample size when you begin the sampling process.
Spl-typ Stands for Sample Type. Choose the type of sampling you
want to use; bulk or dribble.
Bulk sampling is an automated sampling method. You place all
the items to be sampled on the scale at the same time and the
scale will automatically calculate and display the count.
Dribble sampling requires one more step than bulk sampling
You can count the items to be sampled onto the scale and then
press the SAMPLE key to begin the piece weight calculation.
This can be handy if the itemsare more easily counted onto the
scale one at a time versus all at once.
Choices: SPL-bul (bulk) and SPL-dri (dribble)
AccY-Lo Stands for Accuracy Low. Choose the minimum desired
sample accuracy. Reducing sample accuracy allows fewer
sample parts.
Choices: ACC-Off, ACC-95%, ACC-98%, ACC-99%

14 PC-905 Counting Scale Service Manual
Using the Menu
Forthe end user,choosingahigher accuracymaycauselarger
sample sizes to be prompted by the scale and possibly slower
display of the count.
rEV-Cnt Stands for Reverse Count mode. There are two modes of
reverse counting. In mode 1 the user removes an unknown
number of items from the scale, then adds back a specified
number of items. Piece weight is calculated and count is
shown. In mode 2 the user is prompted to remove a specific
number of items, press the SAMPLE key and the display will
show the count of items on the scale. Choose between the two
modes using this menu.
Choices: rEVCnt1, rEVCnt2
PiE-UPd Stands for Piece Weight Update. Use this to automatically
calculate a new piece weight based on using the rounded,
displayed count value. Initial piece weight = sample weight /
sample size. The updated piece weight = bulk weight / rounded
displayed count.
Thisadjustment is done only whena bulksample placedonthe
scaleexceedstheoriginalsamplesizebut is lessthantwicethe
original sample size. The original piece weight is adjusted
during this process.
This feature is disabled if piece weight entry is used.
Choices: oFF, on
PiE-rnd Stands for Piece Weight Rounding. This forces a rounding of
the piece weight obtained using the percentage factors listed
below in the choices. This can make counts more repeatable
and predictable.
Choices: oFF, 0.5 PCt, 1 PCt, 2 PCt
The higher the percentage picked, the more the piece weight is
rounded and the more repeatable and predictable the counts.
This may also mean less accurate counts.
Pie-rPt Stands for Piece Count Repeat. This causes the scale to
remember the last display weight and count. If the next
weighment is the same weight or within the number of divisions
selected, the last displayed count will be repeated.
PiE-Stb Stands for Piece Weight Stabilization. This causes the scale to
compare a newly calculated piece weight with the existing
piece weight. If the new piece weight is within the selected
percentage of the existing piece weight, the scale will continue
to use the existing piece weight.
AUto-bS StandsforAutomaticBaseSwitching:(Youmusthaveselected
andconfiguredaremotebaseforthisfunctiontowork.)Choose
to enable or disable auto base switching mode.
Auto base switching lets you perform sampling on the local
baseand thescale willautomatically switchto theremotescale
for counting. When enabled (ON) all sample procedures will be
performed on the internal base regardless of the current active
base.
Choices: oFF, on

PC-905 Counting Scale Service Manual 15
2.2 CONFIGURATION Menu
2.2 CONFIGURATION Menu
This menu, shown in Figure 2.4, covers items adjusting the scale function
but not affecting weighing function.
Figure 2.4 CONFIG Menu
idLE Stands for Idle. Use this to select the number of minutes before
the scale will automatically shut off during inactivity. The timer
resets if akey is pressed, iftheweightchangesor thereis serial
port activity. Once the scale turns off, press the SAMPLE key
to restart.
Choices: oFF, 5, 10, 20, 30, 60
This feature is normally reserved for use on battery operated
models.
bACLitE Stands for Backlight. Use this to set the display backlight
feature to on, off or automatic. Choose ON to run the backlight
continuously. Choose OFF to disable the backlight. Choose
AUTO to have the backlight on when there is scale activity.
After 10 seconds of inactivity, the backlight will shut off. To
extend battery operation, select OFF or AUto.
Choice: on, OFF, AUto
UnitS Stands for Units of Measure. Use this to enable or disable units
of measure. If disabled, a unit of measure is not available when
pressing the UNITS key.
Choices: LB, 1000g (kg), g, oz
UPdAtE This stands for Display Update Rate. Select the number of
display updates per second.
Choices: 1, 2, 8, 16
A higher display update rate means more new weight or count
values can be displayed per second as load is applied. This
means faster response of the display to changes in weight.

16 PC-905 Counting Scale Service Manual
Using the Menu
2.3 CALIBRATION Menu
Use the menu shown in Figure2.5 to calibrate the local and/or remote base..
Figure 2.5 CALIBRATION Menu

PC-905 Counting Scale Service Manual 17
2.4 Calibrating the Local Base
2.4 Calibrating the Local Base
This section shows the step by step instructions for calibrating the local
scale. Calibrating the remote base is covered in section 2.5.
1. Access the menu using the steps in Accessing the Menu on page 9.
CoUnt is displayed.
WARNING:
Certified weights are required for
NTEP applications and will insure
more accuracy.
2. Press the SAMPLE key twice…
CALib is displayed.
3. Press the ZERO key…
If you have a remote base installed, you are given two choices;
LoCAL and rbASE.
4. Use the SAMPLE or TARE keys to toggle between the choices. Press
the ZERO key when LOCAL is displayed…
PoUnd or 1000 g (kg) is displayed. This is for choosing the unit of
measure of your test weights.
5. Use the SAMPLE or TARE keys to toggle between the choices. Press
the ZERO key when your choice is displayed…
Press the COUNT/WEIGHT key
during the calibration procedure to
back up one step. If you back up all
the way to the CALib display, the
previous calibration is restored.
During calibration the display may
show bUSY if scale motion is
detected. If scale is not stable
within 10 seconds, a calibration
abort will occur. Repeat the
calibration procedure or check
diagnostics for error conditions.
Current capacity setting is displayed.
Choices are (for pound): 10, 25, 50, 100
(for kilograms): 5, 12, 25, 50
6. Use the SAMPLE or TARE keys to scroll through the choices. Press
the ZERO key when your choice is displayed…
The current countby value is displayed.
7. Use the SAMPLE or TARE keys to scroll through the choices. See
Figure 2.6. Press the ZERO key when your choice is displayed…
LoAd 0 is displayed.
8. Remove all weight from the scale and press the ZERO to continue…
bUSY is displayed while the scale obtains a stable zero value.
Display then shows LoAdxxx. xxx is the full scale capacity.
9. Use the SAMPLE or TARE keys to scroll through the choices for
alternate calibration weights for your scale. See the table below.
Press the ZERO key when your choice is displayed…

18 PC-905 Counting Scale Service Manual
Using the Menu
10. Using certified test weights, load the chosen calibration weight onto
the scale. Press the ZERO key to complete calibration…
bUSY, then donE are briefly displayed, then CALib is displayed.
11. The scale is now calibrated. Move to the next menu item, SCALE by
pressing the SAMPLE key.
The available countby values for the different capacity scales (local base
only) in the four available units of measure are shown in Figure 2.613 below.
Default values are shown in bold type. The countby selected automatically
selects the other three unit of measure countbys from the same column.
Figure 2.6 Available Countby Values for Local Base
Capacity (lb) Available countby values
10 .002 .001 .0005 .0002 .0001
25 .005 .002 .001 .0005 .0002
50 .01 .005 .002 .001 .0005
100 .02 .01 .005 .002 .001
Capacity (kg) Available countby values
5 .001 .0005 .0002 .0001 .00005
12 .002 .001 .0005 .0002 .0001
25 .005 .002 .001 .0005 .0002
50 .01 .005 .002 .001 .0005
Capacity (g) Available countby values
5000 1 .5 .2 .1 .05
12000 2 1 .5 .2 .1
25000 5 2 1.5 .2
50000 10 5 21.5
Capacity (oz) Available countby values
160 .05 .02 .01 .005 .002
400 .1 .05 .02 .01 .005
800 .2 .1 .05 .02 .01
1600 .5 .2 .1 .05 .02

PC-905 Counting Scale Service Manual 19
2.5 Calibrating a Remote Base
2.5 Calibrating a Remote Base
This section shows the step by step instructions for calibrating the remote
scale.
1. Access the menu using the steps in Accessing the Menu on page 9.
CoUnt is displayed.
WARNING:
Certified weights are required for
NTEP applications and will insure
more accuracy.
2. Press the SAMPLE key twice…
CALib is displayed.
3. Press the ZERO key…
If you have a remote base installed, you are given two choices;
LoCAL and rbASE.
4. Use the SAMPLE or TARE keys to toggle between the choices. Press
the ZERO key when rbASE is displayed…
PoUnd or 1000 g (kg) is displayed. This is for choosing the unit of
measure of your test weights.
Press the COUNT/WEIGHT key
during the calibration procedure to
back up one step. If you back up all
the way to the CALib display, the
previous calibration is restored.
During calibration the display may
show bUSY if scale motion is
detected. If scale is not stable
within 10 seconds, a calibration
abort will occur. Repeat the
calibration procedure or check
diagnostics for error conditions.
5. Use the SAMPLE or TARE keys to toggle between the choices. Press
the ZERO key when your choice is displayed…
Current capacity setting is displayed. See Figure 2.7 for list of
available capacities.
6. Use the SAMPLE or TARE keys to scroll through the choices. Press
the ZERO key when your choice is displayed…
The current countby value is displayed. See Figure 2.7 for list of
available countby values.
7. Use the SAMPLE or TARE keys to scroll through the choices. See
Figure 2.7. Press the ZERO key when your choice is displayed…
LoAd 0 is displayed.
8. Remove all weight from the scale and press the ZERO to continue…
bUSY is displayed while the scale obtains a stable zero value.
Display then shows SPAn1xxxxx. xxxxx is the mid-span
calibration value.
Explanation note: Theremotebase can havethree calibrationpoints,zero,
mid-span and full span. The zero point is acquired at the beginning of this
step. Span1 is the mid-span calibration point. Span2 is the full span
calibration value. You can skip the mid-span point for a two point calibration.
To skip the mid-span calibration point, press the ZERO key and go
to step 11
To do the three point calibration continue with step 9.
9. Use the 50% default value or key in the mid-span calibration weight. It
must be between 5% and 50% of capacity
10. Load the mid-span calibration weight and press the ZERO key…
bUSY is briefly displayed followed by SPAn2xxxxx.
11. With SPAn2xxxxx displayed, use the default value of 100% or key in
the final calibration point. It must be between 10% and 100% of
capacity.

20 PC-905 Counting Scale Service Manual
Using the Menu
12. Load the entered weight onto the scale and press the ZERO key…
bUSY is briefly displayed followed by donE and then CALib.
13. The scale is now calibrated. Move to the next menu item, SCALE by
pressing the SAMPLE key.
Figure 2.7 Available Countby Values for Remote Base (Default
values are shown in bold type)
Capacity (lb) Available countby values
50 .01 .005 .002 .001 .0005
100 .02 .01 .005 .002 .001
200/250/300 .1 .05 .02 .01 .005
500 .2 .1 .05 .02 .01
1000 .5 .2 .1 .05 .02
2000/2500 1.5 .2 .1 .05
5000 21.5.2.1
10000 52 1 .5 .2
20000 10 521.5
Capacity (kg) Available countby values
25 .005 .002 .001 .0005 .0002
50 .01 .005 .002 .001 .0005
100/125/150 .05 .02 .01 .005 .002
250 .1 .05 .02 .01 .005
500 .2 .1 .05 .02 .01
1000/1250 .5 .2 .1 .05 .02
2500 1.5 .2 .1 .05
5000 21.5.2.1
10000 52 1 .5 .2