Salter Brecknell 335 User manual

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Model 335 Postal Scale
User Manual
1.1 Introduction
Designed for use within stable environments where fluctuation of
temperature, humidity and vibration are limited. The scale features a
weight hold function allowing you to view the weight of an item that is too
large and obstructs the weight display. The 335 also includes a units
switching function allowing you to weigh items in lb/oz, kg, or g.
Use the flip tray to weigh large envelopes or hold tubes/packages in place
on the weight tray.
The Model 335 includes a blue backlit display. The display will activate
upon power up and when the scale is in use for weighing. To save battery
life the backlight will turn off after seven seconds of no use.
The Model 335 Postal Scale,
shown at right, is an
affordable solution for many
applications. Perfect for use
in the office or home to weigh
letters and small packages.
The 335 includes a USB
interface that will provide
power and communication
with your computer and 3rd
party USPS software.

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1.2 Unpacking the scale
Check packaging and scale for any obvious evidence of damage.
Immediately report shipping damage to Salter Brecknell.
Remove contents from packaging, your product should include:
1. Model 335 scale
2. One USB cable
If you are missing an item please contact you Salter Brecknell dealer for
immediate replacement at no charge, shipped via UPS ground.
1.3 Installing the scale
1. Mount the scale on a stable, level surface that is free from air
currents, rapid temperature changes and vibration. These may
affect the weighing accuracy or the stability of the displayed weight.
2. Carefully install, do not force, the weight platter on top of the
mounting posts. Make sure the weight platter does not touch any
adjacent surfaces.
3. Be sure all feet are in contact with the counter.
4. Plug the USB cable into the back of the scale and into a USB port
on a computer to supply power to the scale. You may use a 9v
battery, not supplied, to power the scale. See Installing or
Changing the Battery on page 3
5. Turn the unit on for five minutes, to allow the electronics and load
cell to warm up to room temperature.
6. Place a known weight on the scale to test the weighing accuracy.
Your scale should display the correct weight.
Troubleshooting Tip!
If your scale is not weighing accurately upon
installation, calibrate the scale. See Calibration
on page 9.

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1.4 Operating Instructions
1.4.1 Installing or Changing the Battery
Your Model 335 bench scale can operate on one 9 volt battery. The
expected life of the battery is 60 hours of normal use.
If Lo. B is displayed, this indicates the batteries are low. After this appears,
the scale will turn off in approximately one minute.
To change the battery
1. Remove the battery cover on the bottom of the scale, shown in
Figure 1.1.
Figure 1.1 Battery changing
2. Remove the old battery.
3. Insert the new battery, making sure you align the battery into the
correct positive (+) and negative (-) orientation.
4. Replace the battery cover.

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1.4.2 Annunciators and Key Functions
The 335 has a series of arrow annunciators along the bottom of the display
that point at labels to show you the current unit of measure, if the unit is in
Hold mode, if there is an active tare and if the scale is at zero weight.
Below are descriptions of the three key functions.
Key name Function
Hold / Unit Quick press this key to activate Hold mode. An arrow above Hold
will flash until weight is stable, then a beep sounds and the arrow
will remain lit. Place your item on the scale, allow two seconds for a
stable weight reading, Once you remove the item the weight will be
held in the display until you quick press the key again.
Press and hold for 3 seconds to switch to the next unit of measure
or continually hold to cycle through the units of measure (kg, g, lb,
oz). An icon above the kg, g, lb, oz label will light.
Zero / ON / OFF With the scale turned off and no weight on the scale, quickly press
this key to power On the scale. On power up the scale can zero up
to 10% of capacity.
To turn off, press and hold for more than 3 seconds.
To Zero the scale, press and hold this key for less than 2 seconds
to return the scale to zero weight. You can zero of up to 2% of
capacity.
Tare Quick press this key to perform a Tare function. An arrow above
Tare on the display will light. Press this key to remove the weight of
a container from the display and return the scale to zero weight.
Once you remove your tare container, press this key again to
return the scale to normal weighing.

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1.4.3 Standard Weighing
Follow these steps to perform standard weighing:
1. Press the Zero / ON / OFF button to turn the scale on…
The scale beeps and performs a test sequence. If
everything is OK, the display will show zero weight and the
scale is ready for use.
2. Press the Zero / ON / OFF key if the display is not showing zero
weight.
3. Place your item on the weight platter…
The weight is displayed. It may take up to 2 seconds for the
weight to stabilize.
1.4.4 Changing Unit of Measure
Press and hold the Hold / Unit key until you hear a beep and the
annunciator arrow moves to the next unit of measure. If you continue to
hold down the Hold / Unit key, the annunciator will continue to move to the
next unit of measure every 2-3 seconds (lb/oz, kg, g). Release the key
when the desired unit is highlighted.
The scale will retain the unit of measure selected, even after power off,
until you change the unit of measure.
1.4.5 Tare Weighing
If your are using a container to weigh items and want to see the net weight,
place the container on the scale and quick press the Tare key for less than
2 seconds. The display should show 0.000 weight, and an arrow will light
above Tare in the display window, indicating the tare feature is active.
Place your items in the container, to determine the net weight.
Upon completion of your tare weighing, after
removing your container, the display will show a
negative weight. Quick press the Tare key for
less than 2 seconds to return the scale to zero
gross weight.

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1.4.6 Weight Hold Function
The weight hold feature allows you to weigh letters or packages larger than
the weight platter that would cause the size of the item to block the weight
display window.
The weight hold features allow you to lock a stable weight on the display
after removing your item.
1. With the scale on and at zero weight, quick press the Hold / Unit
key…
An arrow will light above HOLD to indicate weight hold is in
effect.
2. Place your item on the scale, allow two seconds for the weight to
stabilize…
A beep will indicate the weight is stable. The weight of the
item will be held on the display.
3. Remove your item and read the weight on the display.
4. Quick press the Hold / Unit key again to return the scale to normal
weighing mode.
1.4.7 Auto Power-Off
To converse battery life and electricity, the Model 335 scale will
automatically power off after 5 minutes of no use or no change in weight.
If connected to your USB port, you should turn off this feature. Press and
hold the Tare key for 5 seconds, AU.oFF is displayed. The auto power off
feature has now been turned off.
To turn the Auto Power Off feature back on, press and hold the TARE key
for 5 seconds, AU.on is displayed. The auto power off feature has now
been turned back on.

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1.4.8 USB Interface
The Model 335 postal scale includes a USB virtual com port interface that
is compatible with Windows 98, XP and Vista.
Download and install the 335 USB driver from www.salterbrecknell.com.
See the Downloads page.
There is an Active X program on the Salter Brecknell website if you want
to do your own customized scale interface. Check the Downloads page
for the 335 Active X program.
There is a United States Postal Service (USPS) program available for use
with this scale. See the included card for complete information.
After installing the USB driver, the PC will recognize the new hardware
when the scale is connected and powered up. Using your Windows Control
Panel, find and make note of the COM port setting for USB-SERIAL
CH340.
Configure your com port for 2400 Baud, 8 data bits, no parity, 2 stop bits.
Make sure you do not use the DTR and CTR.
1.4.9 Model 335 Interface Format
The Model 335 continuously sends the following format 3 times per
second.
<STX>X X X # # # # # <CR>
Definition of formats:
<STX> = Start of Text Character (02 hex)
X= Status Characters from scale
#= Status characters from scale
<CR> = Carriage Return character (hex 0DH)
1.5 Cleaning and Care
Use a damp cloth with mild detergent to clean your scale.
Handle the scale with care. Precision scales include sensitive load cells.
Dropping the unit or placing weights on the scale that are heavier then the
rated capacity of your scale may cause damage to the load cell.

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1.6 Troubleshooting
Symptom Possible Cause Remedy
Cannot turn on Batteries are low
Incorrectly installed battery
Replace batteries, check
polarity
Poor weighing accuracy Improper calibration
Unstable environment
Scale was not zeroed prior to
use
Tare function is active
Displaying incorrect weight
Perform calibration
Move scale to stable
location
Press the ZERO key to
zero the scale prior to
use
Press Tare key to
remove tare weight held
in memory
Ensure correct unit of
measure is active
CAL. Er displayed Unstable environment
Incorrect calibration weight
used
Move scale to suitable
location
Use correct calibration
weight
Err2 displayed Overload Zero Error
Normal Calibration condition
Load cell is damaged
Excess weight applied to
scale upon zero or power
on, remove weight
Remove weight
Err1 displayed Under load Zero Error Verify weight platter is
installed correctly, power
off then on
Perform Calibration
_ _ _ _ _ displayed Overload Condition Excess weight applied to
scale, remove weight

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1.7 Calibration
From time to time, all scales may require calibration to provide accurate
weighing. When calibrating your scale, you are teaching the scale a zero
reference point and a known accurate weight.
The MODEL 335 allows you to calibrate the scale using lb or kg weights.
1.7.1 Calibrating your scale using LB weights
1. Make sure there is no weight on the scale, and the scale is off.
2. Press and hold the Tare key, then press the Hold / Unit and Zero
/ ON / OFF key until the display shows 15.00 and release all the
keys.
3. Press the Hold / Unit key to calibrate the scale using a LB
weight…
35,0.0 is displayed. This is the amount of test weight you
need to calibrate the scale.
4. Press the Tare key to accept…
The scale will display the internal counts 9000—11000.
5. Press the Tare key to accept and to perform the zero calibration…
0,0.0 will be displayed briefly, then the internal counts will be
displayed again.
6. Place your 35 lb weight on the scale and press the Tare key to
perform calibration…
35,0.0 is displayed briefly, then the scale returns to normal
weighing mode and Err 2 is displayed.
7. Remove the weight from the scale and press the Zero / ON / OFF
key…
The scale will show 0,0.0 weight.
You must close any Windows program used
with the Model 335 before attempting to
calibrate the scale.

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1.7.2 Calibrating your scale using KG weights
1. Make sure there is no weight on the scale, and the scale is off.
2. Press and hold the Tare key, then press the Hold / Unit and Zero
/ ON / OFF key until the display shows 15.00 and release all the
keys.
3. Press the Tare key to accept…
The scale will display the internal counts 9000—11000.
4. Press the Tare key to accept and to perform the zero calibration…
0.00 will be displayed briefly, then the internal counts will be
displayed again.
5. Place your 15 kg weight on the scale and press the Tare key to
perform calibration…
15.00 is displayed briefly, then the scale returns to normal
weighing mode and Err 2 is displayed.
6. Remove the weight from the scale and press the Zero / ON / OFF
key…
The scale will show 0.00 weight.
If CAL.Er appears, this indicates an error in
calibration. Repeat steps 1-7. If CAL.Er
continues to appear you may have a damaged
load cell or electronics.
WARNING! Calibrating your scale with
inaccurate or the incorrect weights as
defined in Stabilization Up to 2 seconds to
stable weight reading on page 11 will cause
your scale to weigh incorrectly.

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1.8 Specifications
Capacity and Resolution
Dual Range 0-2 lb x 0.1 oz / 2-35 lb x 0.2 ounce
0-1 x 0.01 kg / 1-16 x 0.02 kg
0-1,000 x 10 g / 1,000– 16,000 x 20 gram
Accuracy +/- 3 divisions (division = resolution)
Operating Temp 5° - 35° C / 41° - 95° F
Display Blue backlight display with 0.5” H weight
digits
Tare Range Up to 100% of max. capacity, subtractive
(subtract tare weight from max capacity =
new max capacity)
Stabilization Up to 2 seconds to stable weight reading
USB Computer must have USB 2.0 or above

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Salter Brecknell Weighing Products
1000 Armstrong Dr.
Fairmont, MN 56031
Toll free: 800-637-0529
Tel: [phone] Fax: [phone]
e-mail: [email protected]
www.salterbrecknell.com
October 2009 335 Postal_u_en_500479.fm AWT35-500479 Issue AA