NCI 7800 User manual

User’s
Manual
Model
7800
Family
Weight
Classifiers
7880
7820
7829
7824
7840
7885

Model 7800 Family Weight Classifiers User’s Manual
2
Risk of electrical shock. Do not remove cover. No user serviceable
parts inside. Refer servicing to qualified service personnel.
Weigh-Tronix reserves the right to change
specifications at any time.
CAUTION
10/10/05 7800_U.P65 PN 7424-15170i e2 Printed in USA

Model 7800 Family Weight Classifiers User’s Manual 3
Table of Contents
Specifications ....................................................................... 4
Initial Setup .......................................................................... 7
Operation ............................................................................. 9
Diagnostics Mode ............................................................... 15
Configuration Mode ............................................................ 20
Calibration Mode ................................................................ 24
Gravity Mode ...................................................................... 27
Re-Calibration Mode .......................................................... 28
Review/Test Scale Settings ................................................ 29
Communication .................................................................. 31
Error Codes ........................................................................ 34
Troubleshooting ................................................................. 35
Spare Parts Listing ............................................................. 37

Model 7800 Family Weight Classifiers User’s Manual
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The NCI 7800 models are digital electronic parcel
bench scales specifically designed for shipping
applications and are Legal-for-Trade. The scales
have built-in intelligence that enables them to be
easily interfaced with a computer or other data-
processing device.
Model Capacity (lb) Capacity (kg) n(max)
7820-50 100 x 0.02 lb 50 x 0.01 kg 5000d
7820-70 150 x 0.05 lb 60 x 0.02 kg 3000d
7820-75 150 x 0.02 lb 75 x 0.01 kg 7500d
7880-50 100 X 0.02 lb 50 x 0.01 kg 5000d
7880-75 150 x 0.05 lb 75 x 0.02 kg 3750d
7880-125 250 x 0.05 lb 100 x 0.02 kg 5000d
7880-150 300 x 0.1 lb 150 x 0.05 kg 3000d
7885-75 150 x 0.05 lb 75 x 0.02 kg 3750d
7829-125 250 x 0.05 lb 100 x 0.02 kg 5000d
7840-125 250 x 0.05 lb 100 x 0.02 kg 5000d
7840-150 300 x 0.1 lb 150 x 0.05 kg 3000d
7824-125 250 x 0.05 lb 100 x 0.02 kg 5000d
7824-150 300 x 0.1 lb 150 x 0.05 kg 3000d
Model 7820
United States: NTEP #95-070
Canada: Ministry of Industry #AM-5076
For use as a Class III device from +5°C through
+40°C
Model 7885
United States: NTEP #02-069
Canada: Ministry of Industry (#AM-5507)
For use as a Class III device from +5°C through
+40°C
Models 7824, 7829, 7840, 7880
United States: NTEP #95-121
Canada: Ministry of Industry #AM-5099
For use as a Class III device from +5°C through
+40°C
Specifications
Description
Capacity/Resolution
Agency
Certificates
of Conformance
If unit is to be
used as a
commercial
device, all local
reporting and
registration
requirements
must be fol-
lowed.

Model 7800 Family Weight Classifiers User’s Manual 5
Model 7820: 14" L x 12.5" W x 4.1" H
Model 7880: 18" L x 18" W x 4.6" H
Model 7885: 18" L x 18" W x 3.0" H
Model 7829: 20" L x 20" W x 5.3" H
Model 7840: 18" L x 24" W x 4.6" H
Model 7824: 24" L x 24" W x 4.6" H
UL/CSA approved in-line power supply with 6’
line cord. (7885 uses wallmount style)
Input: 120 VAC +10%-15%, Standard 3 wire w/
ground
Output: 15 VDC @.3 Amps DC
60 Hz Standard
0.1 amp maximum
42ºF – 104ºF (5ºC – 40ºC)
10% to 95% RH (non-condensing)
Model 7820: Die cast aluminum base with a
stainless steel weigh platter.
Overload protection: Adjustable center stop, fixed
corner stops.
Model 7885: Painted mild steel base with
stainless steel weigh platter.
Overload protection: Fixed center and corner
stops.
Models 7824, 7829, 7840, 7880: Painted mild
steel base with stainless steel weigh platter.
Overload protection: Adjustable center and
corner stops.
½" high, six-digit LCD. Internal display standard
on all models except 7885 (remote only)
Key panel with ZERO and TEST keys.
Optional remote display with 7 ft. cable.
Level bubble located under weigh platter. Adjust-
able feet in each corner to level the scale.
Dimensions
Power Supply
Frequency
Power Requirements
Operating Temperature
Construction
Display
Scale Leveling

Model 7800 Family Weight Classifiers User’s Manual
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Zero Window
Under Capacity Limits
Over Capacity Limits
Sealing
Internal Counts
Dynamic Response
Initial automatic zero setting is ±10% of maxi-
mum capacity—active at power up. Manual zero
setting range is ±2% of maximum capacity—
active using the ZERO key.
Under capacity indication will be given with
dashes appearing on the bottom line of the
display whenever the display is more than 2
percent below the initial zero value.
Over capacity indication will be given with dashes
appearing in the upper line of the display when-
ever the weighed item exceeds 9 divisions over
the rated capacity of the unit. The scale will use
the Initial zero value for reference for over
capacity determination.
Access to the calibration switch can be secured
with a lead wire or pressure sensitive security
seal. The remote and primary indicators have no
metrological features that require the use of a
security seal.
The scale has 100,000 internal counts.
The time from when weight is applied to the scale
until a stable weight display is displayed:
0–1000d 1.5 seconds
1000d+ 2.0 seconds
maximum mean average

Model 7800 Family Weight Classifiers User’s Manual 7
Initial Setup
Factory default settings: 9600 baud, 7 data bits,
even parity, 1 stop bit.
Standard 9-pin pass through RS-232 interface
cable included. Not a null modem.
RS-232 bidirectional, configurable 1200 to 19.2K
baud. Transmits weight and scale status when-
ever ASCII “W” <CR> is sent by a remote device.
1. Remove contents of the shipping container.
2. Inspect the scale for evidence of shipping
damage. Immediately report any damage to
the shipper.
1. Mount the scale on a stable, level surface
that is free from air currents and vibration. Be
sure the scale platter does not touch any
adjacent surfaces.
2. To install the scale surface flush with a
countertop, use the dimensions on the
following page to guide construction.
Communications
Unpacking the Scale
Installing the Scale

Model 7800 Family Weight Classifiers User’s Manual
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Scale Dimensions Min. Cut-Out Dimensions
D12.5 in. (31.7 cm) 13.25 in. (33.7 cm)
W14 in. (35.6 cm) 14.75 in. (37.5 cm)
H4.1 in. (10.4 cm)*
*Adjustable to 4.6 in. (11.7 cm)
Scale Dimensions Min. Cut-Out Dimensions
D18 in. (45.7 cm) 18.75 in. (47.6 cm)
W18 in. (45.7 cm) 18.75 in. (47.6 cm)
H4.6 in. (11.6 cm)*
*Adjustable to 5.1 in. (12.9 cm)
Scale Dimensions Min. Cut-Out Dimensions
D18 in. (45.7 cm) 18.75 in. (47.6 cm)
W18 in. (45.7 cm) 18.75 in. (47.6 cm)
H3.0 in. (7.6 cm)*
*Adjustable to 3.5 in. (8.9 cm)
Scale Dimensions Min. Cut-Out Dimensions
D20 in. (50.8 cm) 20.75 in. (52.7 cm)
W20 in. (20.8 cm) 20.75 in. (52.7 cm)
H5.3 in. (13.5 cm)*
*Adjustable to 5.8 in. (14.7 cm)
Scale Dimensions Min. Cut-Out Dimensions
D24 in. (61.0 cm) 24.75 in. (62.9 cm)
W18 in. (45.7 cm) 18.75 in. (47.6 cm)
H4.6 in. (11.7 cm)*
*Adjustable to 5.1 in. (12.9 cm)
Scale Dimensions Min. Cut-Out Dimensions
D24 in. (61.0 cm) 24.75 in. (62.9 cm)
W24 in. (61.0 cm) 24.75 in. (62.9 cm)
H4.6 in. (11.7 cm)*
*Adjustable to 5.1 in. (12.9 cm)
3. Loosen the collars or jam nuts on the leveling
feet. Level the scale by using the level bubble
under the scale platter as a guide. Be sure all
four feet are in firm contact with the counter,
then tighten all collars and jam nuts.
4. Make sure all power cords, remote display
cables, etc., are not touching the live weigh-
ing surface.
5. Plug the unit into an appropriate voltage
outlet that is properly grounded.
Model 7820
Model 7880
Model 7829
Model 7840
Model 7824
Model 7885

Model 7800 Family Weight Classifiers User’s Manual 9
When the scale is first powered on, it will perform
a test sequence. During this sequence, the
display will show the following:
• The model number and the software
revision level.
• A numeric counting test for all segments of
the display. During this test, a test of
Random Access Memory (RAM) and a test
of Read Only Memory (ROM) is performed.
If everything is OK, the display will show zero
weight and the scale is ready for use.
1. With the scale powered on, make sure the
scale platter is empty and the display is at
zero. If it is not, press the ZERO key...
0.00 is displayed.
2. Place an item to be weighed on the scale
platter...
The scale will display the gross weight.
3. Remove the item from the scale platter.
Operation
Power Up Test Sequence
If RAM or ROM error
is reported, you must
press the TEST key to
acknowledge the
condition. See Error
Codes section.
Performing a Normal
Weighment
When first powered
on, if the scale is
outside the ± 10% zero
window, center dashes
are displayed. “- - - -”
If necessary, reapply
power to reset the
initial zero setting.
Refer to the Trouble-
shooting section if the
problem persists.

Model 7800 Family Weight Classifiers User’s Manual
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Operation Controls
7885 or Optional
Remote Display
ZERO Key – The ZERO key will zero the scale if
weight is stable, and acts as the NO or SCROLL
key in the Menu Mode and as the INCREASE
key in the Gravity Mode.
TEST Key – The TEST key can be used to
perform the initial power-up test sequence, recall
diagnostic routines, or view the configuration
information. This key also functions as YES or
ACCEPT in the Menu Mode and as the DE-
CREASE key in the Gravity Mode.
All NCI 7800 bench scales, except the 7885, can
have an optional remote display. If a remote
display with keyboard is used, then Switch 3
(shown in Figure 1) determines which display
keyboard is funcitional.
Switch 3 Settings:
Closed= internal display keys operational
Open= external display keys operational
The remote display must be connected to the
RJ45 port (DISPLAY) prior to power up to
operate properly.
7820, 7880, 7829, 7840 and 7824 resident display

Model 7800 Family Weight Classifiers User’s Manual 11
Top View of 7820 Scale with Platter Removed
Figure 1
7820 Switch
Location
The 7800 models power up ready for weighing
operations. Access the Menu mode by setting
Switch 1 shown in Figure 1 or 2 to the OPEN or
Menu mode position.
Access the Gravity setting mode by setting
Switch 2, shown in Figure 1 or 2, to the OPEN or
Gravity mode position.
Accessing the
Menu Mode
Accessing the
Gravity Mode

Model 7800 Family Weight Classifiers User’s Manual
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With Switch 1 in the Menu mode or OPEN
position, there are four modes available to you.
They are as follows:
DIAG (Diagnostic Mode) – To test areas of
the scale’s function
CONF (Configuration Mode) – To configure
the scale for your application
CAL (Calibration Mode) – To calibrate the
scale
RE-CAL (Recalibration Mode) – To change
resolution and rounding type
The structure for these menus is shown in Figure
3. Specific information about each mode followed
by step-by-step instructions for accessing them
are described in the following pages.
With Switch 2 in the Gravity Mode or OPEN
position, you may increase the local gravity value
by pressing the ZERO key, or decrease the value
by pressing the TEST key.
Bottom View of Models 7824, 7829, 7840,
7880 and 7885
Figure 2
7824, 7829, 7840,
7880, 7885 Switch
Location
Menu Mode
Gravity Mode

Model 7800 Family Weight Classifiers User’s Manual 13
Figure 3
Menu Structure

Model 7800 Family Weight Classifiers User’s Manual
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The NCI 7800 bench scales allow calibration
using less than full capacity weights. See Table 1
for alternative weights that can be used to
calibrate your scale for its designated capacity.
Alternative
Capacity Calibration Weights
100 x .02 lb 10, 50, 100 lb
50 x .01 kg 10, 25, 50 kg
150 x .05 lb 10, 50, 150 lb
60 x .02 kg 10, 30, 60 kg
150 x .02 lb 10, 50, 150 lb
75 x .01 kg 10, 50, 75 kg
75 x .02 kg 10, 50, 75 kg
250 x .05 lb 50, 100, 250 lb
100 x .02 kg 10, 50, 100 kg
300 x .1 lb 50, 100, 300 lb
150 x .05 kg 10, 50, 150 kg
Display Baud Parity
12 E 1200 Even
24 E 2400 Even
48 E 4800 Even
96 E 9600 Even
19.2 E 19.2K Even
12 o 1200 Odd
24 o 2400 Odd
48 o 4800 Odd
96 o 9600 Odd
19.2 o 19.2K Odd
12 n 1200 None
48 n 4800 None
96 n 9600 None
19.2 n 19.2K None
*Default Factory Settings
Alternative Calibration
Points
Table 1
Alternative
Calibration Points
Baud Rate and Parity
Options
Table 2
Baud Rate and
Parity Options
*
The databits and stop
bits default values are
7 data bits and 1 stop
bit. These are not
configurable.

Model 7800 Family Weight Classifiers User’s Manual 15
Diagnostics Mode
The Diagnostic (DIAG) Mode menu allows
testing of specific areas of the scale’s function
and viewing of current configuration settings.
Areas to test the scale’s function are:
DISPLAY (DISP) – Shows the version and
revision of the software, followed by a display
segment test.
RAM (RA) – Performs a non-destructive test of
RAM in the processor. Displays PASS or FAIL.
ROM (RO) – Performs a checksum of all loca-
tions of ROM in the processor. Displays PASS or
FAIL.
INPUT/OUTPUT (I/O) – Data is output by the
scale and through the use of a loopback connec-
tor. The data is immediately read back into the
receive channel and verified against what was
sent. PASS or FAIL is displayed. Requires a
jumper (short) between transmit and receive data
lines.
DIVISION TEST, w/AZT (DIV-A) – Weight data
is normalized to 100,000 counts of displayed
resolution. AZT is enabled.
DIVISION TEST, w/o AZT (DIV-N) – Weight data
is normalized to 100,000 counts of displayed
resolution. AZT is disabled.
Areas to view current configuration settings are:
Filter, Protocol, Baud, Capacity, Type, Units,
Prtout and Gravity Setting.
Diagnotic (DIAG) Mode
Tip: Quickly and easily
gain access to the
Diagnostic mode
directly from the front
panel without opening
the scale or setting
switches as follows:
Press and hold the
TEST key. The display
will flash 78--, the
program version, and
then “_ _ _ _.” Now
release the TEST key.
To exit the Diagnostic
mode press the ZERO
key until DONE is
displayed, then press
the TEST key to return
to normal weighing
mode.
IMPORTANT: Internal
rocker switches will be
ignored until you exit
this special mode or
power reset the scale.

Model 7800 Family Weight Classifiers User’s Manual
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Follow these steps to access the tests in the
DIAG menu.
1. From normal weighing mode, move Switch 1
to the MENU Mode or OPEN position. (See
Figure 1 or 2).
DIAG is displayed.
2. Press the TEST key...
DISP is displayed. This stands for
display.
3. Press the TEST key to perform the display
test described earlier...
Display test is performed and the display
shows DISP after the test is completed.
4. Press the ZERO key...
RA is displayed. This stands for the RAM
test.
5. Press the TEST key to perform the RAM
test...
PASS or FAIL is displayed briefly; then
RA.
6. Press the ZERO key...
RO is displayed. This stands for the
ROM test.
7. Press the TEST key to perform the ROM
test...
PASS or FAIL is displayed briefly; then
RO.
8. Press the ZERO key...
I/O is displayed. This stands for the
INPUT/OUTPUT test. .
If you encounter any
failure in these tests,
contact your local
Weigh-Tronix dealer.
Press the ZERO key to
scroll through lists of
selections.
Press the TEST key to
make a selection.
To skip a test, press
the ZERO key to scroll
to the next test.

Model 7800 Family Weight Classifiers User’s Manual 17
9. With a loopback connector in place, press
the TEST key to perform the I/O test...
PASS or FAIL is displayed briefly, then
I/O.
10. Press the ZERO key . . .
DIV-A is displayed. This stands for the
high resolution DIVISION TEST W/ AZT
enabled.
11. Press the TEST key to perform this test...
The display shows the weight on the
scale at a resolution of 100,000 counts.
12. Press the TEST key to stop the test...
DIV-A is displayed.
13. Press the ZERO key...
DIV-N is displayed. This stands for the
high resolution DIVISION TEST w/o AZT
enabled.
14. Press the TEST key to perform this test...
The display shows the weight on the
scale at a resolution of 100,000 counts.
15. Press the TEST key to stop the test...
DIV-N is displayed.
16. Press the ZERO key...
FILT is displayed. This stands for filter-
ing.
17. Press the TEST key...
The current filter setting, FAST or SLO,
is displayed.
DIAG will flash every
15 seconds during the
high resolution test as
a reminder that you
are doing a test and
not seeing normal
weight readings.
The remaining
selections are for
viewing current
settings only. You can
scroll through the
menu to verify the
settings, but to make
changes, you must
enter configuration or
calibration.

Model 7800 Family Weight Classifiers User’s Manual
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18. Press the ZERO key...
PROT is displayed. This stands for
protocol.
19. Press the TEST key...
The current serial protocol selection is
displayed.
20. Press the ZERO key...
BAUD is displayed. This stands for baud
rate.
21. Press the TEST key...
The current baud rate and parity selec-
tion is displayed.
22. Press the ZERO key...
CAP is displayed. This stands for capac-
ity.
23. Press the TEST key...
The current capacity/resolution selection
is displayed.
24. Press the ZERO key...
TYPE is displayed. This stands for
rounding type (classifier or scale).
25. Press the TEST key...
The current rounding type, SCALE for
standard rounding or CLASS for classi-
fier rounding, is displayed.
26. Press the ZERO key...
UNITS is displayed. This stands for unit-
of-measure.

Model 7800 Family Weight Classifiers User’s Manual 19
27. Press the TEST key...
The current unit-of-measure LBS (for
pounds) or 1000G (for kilograms), is
displayed.
28. Press the ZERO key...
PRTOUT is displayed. This stands for
output print format.
29. Press the TEST key...
The current output print format is dis-
played. See Table 3 for details.
30. Pres the ZERO key. . .
LOC-GR is displayed. This stands for
local gravity.
31. Press the TEST key. . .
The current local gravity setting is
displayed.
32. Press the ZERO key . . .
CAL-GR is displayed. This stands for
calibration gravity.
33. Press the TEST key. . .
The current calibration gravity settings is
displayed.
34. When you are finished, press the ZERO key,
until DONE is displayed, then press the
TEST key to return to the top menu level...
DIAG is displayed.
Or close Switch 1 to return to normal weigh-
ing mode.

Model 7800 Family Weight Classifiers User’s Manual
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The Configuration (CONF) mode menu allows
scale configuration for your specific application
needs. The items you can configure are as
follows:
FILTERING (FILT) – Choose between FAST and
SLO filtering. SLO should be chosen in areas
susceptible to vibration. Choose FAST filtering
for more stable conditions.
Baud (BAUD) – Choose a baud and parity from
Table 2.
Protocol (PROT) – Select the RS-232 commun-
ication protocol.
NCI – NCI standard
8213 – 8213 compatible (Mettler-Toledo)
3835 – NCI 3835
SMA – Scale Manufacturing Association
AUTO-1 – Auto print operation (Type-1)
AUTO-2 – Auto print operation (Type -2)
PRINT – Manual print operation
PRTOUT – Choose an output data format from
Table 3 for use with AUTO-1, AUTO-2 or PRINT
protocol selection.
Access the menu mode as described in Access-
ing the Menu Mode.
1. From the DIAG display, press the ZERO key
until CONF is displayed, or from the normal
weighing mode, move Switch 1 to the Menu
ode or the OPEN position; then press the
ZERO key until CONF is displayed.
Configuration Mode