Wensar HPB201 User manual

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High Precision Balance
balanceBalanceBBalanceB
aBalance
HPB201, 501, 1001 - Upgraded
Internal Calibration

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Contents
1Technical Specifications........................................................................................................................3
1.1 3 Digits...........................................................................................................................................3
1.2 Proper Use......................................................................................................................................4
1.3 Improper Use..................................................................................................................................4
1.4 Control of inspection, measuring and test equipment ......................................................................4
2Precaution .............................................................................................................................................5
3Transportation and Storage....................................................................................................................5
3.1 Acceptance check...........................................................................................................................5
3.2 Packing...........................................................................................................................................5
4Unpacking & Setup
4.1 Installation Site, Location of Use....................................................................................................5
4.2 Unpacking / Installation..................................................................................................................6
4.3 Mains connection............................................................................................................................6
4.4 Connection of peripheral devices....................................................................................................6
4.5 Adjustment.....................................................................................................................................7
4.6 Calibration.........................................................................................Error! Bookmark not defined.
5Operation...............................................................................................................................................7
5.1 [Power On/OFF].............................................................................................................................8
5.2 TARE.............................................................................................................................................8
5.3 CAL -.............................................................................................................................................8
5.4 UNIT- [multifunctional key]...........................................................................................................8
5.5 Print function [print mode]..............................................................................................................8
5.6 Pieces counting function [counting mode] ......................................................................................8
5.7 Underfloor weighing.......................................................................................................................9
6Density determination (Hydrostatic weighing).......................................................................................9
8Displayinformation / Error messages ...................................................................................................10
9Interface RS 232C ...............................................................................................................................11
10 Configuration &Explain of the function setting....................................................................................12
11 Maintenance and Servicing..................................................................................................................13
12 TROUBLE SHOOTING......................................................................................................................14

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1Technical Specifications
1.1 3 Digits
The laboratory analytical balance is designed to meet the needs of laboratories, industry and commercial
users and it offers very wide range of functions: weighing, piece counting or density determination. All scale
have a built-in standard weight and a precision automatic loading device, our computer controlled
mechanism with precise motors complete the loading and unloading operation of the test weight. The result
is an easy, fast and automatically working mechanism to always get the best results.

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Balance is equipped with precision temperature measurement circuit, the perception of temperature changes
to 0.01 degrees. If the environment temperature change more than 1.5 degrees, the balance will
automatically start the calibration function, to keep the balance of the degree of accuracy of measurement. In
addition, if the last calibration is 3 hours ago, the balance will start an automatic calibration to always keep
good results.
Electromagnetic force compensation technology.
High precision, sensitivity and rapid response time.
High quality materials and an optimized power supply.
High reliability and long service life.
A robust base made of powder coated aluminum cast.
An easy-cleaning, durable and stable metal shell with glass wind protection.
A removable stainless steel pan can be cleaned easily.
A Level Indicator, four adjustable feet.
External calibration, zeroing searches, parts counting function, tare function, density determination
7 Weighing units (g, ct, ozt, oz, GN, dwt, mg).
Large LCD display with backlight, digit height 15 mm.
An integrated RS-232-interface enables you to automatically send the weighing data to PC
Powered by the external mains power cord.
1.2 Proper Use
The balance you purchased is intended to determine the weighing value of material to be weighed. It is
intended to be used as a “non-automatic” balance, i.e. the material to be weighed is manually and carefully
placed in the center of the weighing plate. As soon as a stable weighing value is reached the weighing value
can be read.
1.3 Improper Use
Do not use the balance for dynamic weighing. In the event that small quantities are removed or added to
the material to be weighed, incorrect weighing results can be displayed due to the “stability
compensation” in the balance. (Example: Slowly draining fluids from a container on the balance.)
Do not leave permanent load on the weighing plate. This may damage the measuring system.
Impacts and overloading exceeding the stated maximum load (max) of the balance, minus a possibly
existing tare load, must be strictly avoided. Balance may be damage by this.
Never operate the balance in explosive environment. The balance is not explosion protected.
The structure of the balance may not be modified. This may lead to incorrect weighing results, safety-
related faults and destruction of the balance.
The balance may only be used according to the described conditions. Other areas of use must be released
by manufacturer in document.
1.4 Control of inspection, measuring and test equipment
As part of quality assurance the measuring-related properties of the balance and the available adjusting
weight must be checked regularly.
The responsible user must define a suitable interval as well as the nature and scope of this test

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2Precaution
Environmental conditions: only use indoor, check the detailed environment conditions for temperature
and humidity in the technical details above.
Do not use the scale in any high temperature fluctuations and avoid strong airflows, vibrations and dust.
The balance could never get wet and make sure that the balance is not used in an environment with
extreme temperature and humidity.
Do not use the balance in explosive conditions.
Only use the extender cable, which with ground wire.
If the power line cable is damaged, the appliance must be unplugged immediately and the power line
cable be replaced.
Place the balance on a stable surface and set it horizontally with the help of the adjustable feet and the
spirit level.
The electronic balance is a precision measuring instrument and must be handled with great care.
Violation of limit of weighing range or impact can cause permanent damage to the balance.
The balance needs a warm up time for about 1 hour before using.
Please do not use aggressive cleaning agents (solvents or similar agents), but a cloth dampened with
mild soap suds. Ensure that no liquid penetrates into the device and wipe with a dry soft cloth.
Do not overload the balance more than 20% of maximum load (Max). Do not press the pan with a hand!
By maintenance please notice the information in Chapter “Maintenance and Servicing”.
If the balance seems not to operate properly, unplug it from the mains and do not use until checked by
authorized service.
All repairs and necessary regulations can be made by authorized personnel only.
Carefully read this operation manual before setup and commissioning.
3Transportation and Storage
3.1 Acceptance check
When receiving the appliance, please check packaging immediately, and the appliance itself when
unpacking for possible visible damage.
3.2 Packing
Keep all parts of the original packaging for transportation
Disconnect all cables and remove loose parts before dispatch
4Unpacking, Setup and Commissioning
4.1 Installation Site, Location of Use
The balances are designed in a way that reliable weighing results are achieved in common conditions of use.
You will work accurately and fast, if you select the right location for your balance.
Therefore, observe the following for the installation site:

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Major weighing deviations (incorrect weighing results) may be experienced should electro-
magnetic fields (e.g. due to mobile phones or radio equipment), static electricity accumulations
or instable power supply occur. Change location or remove source of interference.
Place the balance on a firm, level surface;
Avoid extreme heat as well as temperature fluctuation caused by installing next to a radiator or in the
direct sunlight;
Protect the balance against direct draughts due to open windows and doors;
Avoid jarring during weighing;
Protect the balance against high humidity, vapors and dust;
Do not expose the device to extreme dampness for longer periods of time.
Non-permitted condensation (condensation of air humidity on the appliance) may occur if a cold
appliance is taken to a considerably warmer environment. In this case, acclimatize the disconnected
appliance for ca. 4 hours at room temperature.
Avoid static charge of goods to be weighed or weighing container.
4.2 Unpacking / Installation
Carefully remove the balance from the packaging, remove plastic cover and setup balance at the intended
workstation.
1. Take the balance and supplied accessories (a feeder, pan elements) out of the box.
2. Place the balance on a stable ground not affected by mechanical vibrations and airflows.
3. Level the balance with foot screws so that the air bubble in water-level is in the middle.
4. Plug the adapter to the power socket at the back of the balance.
5. Connect the power adapter to an AC220V ± 10% 50Hz ± 1Hz outlet.
Packing List
Balance with Wind Protection
Weighing pan set
Power Cord
Instruction Manual
Check List
Test Certificate
4.3 Mains connection
Before connecting the Power cord check if the printed voltage value is the same as the local supply voltage.
Only use the original supplied mains Powercord. Otherwise there is a risk that the Scale be impaired.
4.4 Connection of peripheral devices
The balance may send data to a computer or a printer through RS232C port.
When cooperating with the balance, a computer should be equipped with a program which enables
processing data from the balance.
Before connecting or disconnecting of additional devices (printer, PC) to the data interface, always
disconnect the balance from the power supply.
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4.5 Adjustment
As the acceleration value due to gravity is not the same at every location on earth, each balance must be
coordinated - in compliance with the underlying physical weighing principle - to the existing acceleration
due to gravity at its place of location (only if the balance has not already been adjusted to the location in the
factory). This adjustment process must be carried out for the first commissioning, after each change of
location as well as in case of fluctuating environment temperature. To receive accurate measuring values it
is also recommended to adjust the balance periodically in weighing operation.
4.6 Internal calibration:
When the balance display is “0” then press the “CAL” key.
The balance turns into the automatic internal calibration status and displays “CAL”, now the internal weight
loading and unloading device for automatic calibration will start their work.
After 30 seconds the display “0”, that means the calibration is finished. In the normal use, the internal
calibration should be used to calibrate the balance.
When there was no calibration within the last 3 hours the scale will calibrate itself.
5Operating Elements
1. Weighing pan 2. Pan support ring 3. Wind protection 4. Underfloor weighing widget
5. Sealing cap 6. Adjustable feet 7. RS232 Interface 8. Level Indicator
9. Power socket 10. AC adapter cable 11. ON/OFF key 12. Calibration key
13.Unit change key 14. Counting key 15.Print key 16.Tare key
6Operation
After new purchase of the balance or after a long storage, you have to calibrate the balance before the first
commissioning. Level the balance with the adjustable feet horizontal until the air bubble in the level is in the
center of the Level Indicator. Give the balance after changing the location a warm-up time min. 1 hour
before using. This time is necessary for the balance to adapt to the eventual temperature.

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6.1 [Power On/OFF]
Press the[On/OFF]button to turn on the balance. The display shows the message "ON".Then
themax.weighing range is displayed. The balance will carry out a self-test (F----1 to F----9). When the
"0.000 g" in display appears, the balance is ready for operation.
Press the [On/OFF] button and keep it pressed, until the display shows the message “OFF”. The balance will
switch off then.
6.2 TARE
When the pan is empty and indication is different than zero press [TARE] key.
Weighing with tare: Place the weighing box and press the[TARE] button. After standstill control the zero
display appears. The weight of the container is now internally saved. Weigh the material, the net weight will
be indicated. The weight of the weighing container will be displayed as a minus number after removing the
weighing container. The tare weight is saved until it is deleted. Remove the load from the balance and press
the [TARE] button. The tare procedure can be repeated as many times as necessary, for example with initial
weighing of several components for a mix (add-on weighing). The limit is reached when the total weighing
range capacity is full.
6.3 CAL - [ nternal Calibration]
The balance has an Internal calibration function.
6.4 UNIT- [multifunctional key]
The [UNIT] - button is a multi-function button.
6.4.1 Weighing unit selection [weighing mode]
Under the weighing mode, use the UNIT key to choose weighing units: g (gram), ct (carat), ozt (troy ounce),
oz (ounce), GN (gran), dwt (pennyweight) and mg (milligram)
1 g = 5 ct
= 0.032150747 ozt
= 0.035273962 oz
= 15.43235835 GN
= 1000mg (0.001g)
6.5 Print function [print mode]
The balance can be connected via the RS232C interface directly to a printer or PC.
Press the “PRINT” key to send the weight to the output device.
6.6 Pieces counting function [counting mode]
Before the balance can count parts, it must know the average part weight (i.e. reference). Proceed by putting
on a certain number of the parts to be counted. The balance determines the total weight and divides it by the
number of parts, the so-called reference quantity (1, 10, 20, 50, or 100). Counting is then carried out on the
basis of the calculated average piece weight.
As a rule: The higher the reference quantity the higher the counting exactness.

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Follow these steps:
a) Place as many pieces to add-up as required by the reference quantity. Press the “COUNT” key, display
“1” that means into the counting mode, Press the [UNIT] button to enter the setting menu. The display
now shows the number "1" and the unit "Pcs". Using the [UNIT] button select the reference quantity (1,
10, 20, 50, or 100).
b) After successful reference determination the current quantity is displayed and the unit “Pcs”.
c) Remove reference weight. The balance is now in piece counting mode counting all units on the weighing
plate.
6.7 Underfloor weighing
Objects unsuitable for placing on the weighing scale due to size or shape may be weighed with the help of
the underfloor weighing device.
Proceed as follows:
Switch off the balance
Open the Sealing cap at the balance bottom.
Suspend hook for underfloor weighing carefully and completely.
Place weighing balance over an opening.
Attach load to hook and carry out weighing procedure.
Always ensure that all suspended objects are stable enough to hold the desired
goods to be weighed safely (danger of breaking).
Never suspend loads that exceed the stated maximum load (max) (danger of
breaking).
Always ensure that there are no persons, animals or objects that might be damaged
underneath the load.
After completing the underfloor weighing the opening on the bottom of the
balance must always be closed (dust protection).
7Density determination (Hydrostatic weighing)
According to the Archimedes’ principle, any object, wholly or partially immersed in a fluid, is buoyed up by
a force equal to the weight of the fluid displaced by the object.In other words, an immersed object is buoyed
up by a force equal to the weight of the fluid it actually displaces.
For the density determination of solid material, the solid is weighed first in air and then in the measuring
liquid. Because of the density of the water is 1.0 g/cm ³, can determine the volume of the displaced water
and also the volume of object. From the weight difference results the buoyancy calculates the density.
The density is determined with help of the underfloor weighing device.
Hydrostatic density determinations succeed only with the objects, which have a
higher density than water (1 g/cm3).
Example:
A piece of metal in the air weight 100 g and weighs 80 g in water. Therefore, the object has 20 g (= 20 cm³)
water displaced. Its volume is therefore 20 cm³. Now it is easy to determine the density of the metal piece.
Density determination of solids

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For the density determination of solid material, the solid is weighed first in air [ A ] and then in the
measuring liquid [ B ]. If the density of the buoyancy medium [ ρo ] is known, the density of the solid [ ρ ] is
calculated as follows:
  
   
= Density of the sample
= Weight of the sample in air
= Weight of the sample in the measuring liquid
= Density of the measuring liquid
Determining density of liquids
For density determination of liquids, a glass sinker is used, whose volume ([ V ] see embossing) is known.
The glass sinker is weighed first in air [ A ] and then in the liquid [ B ] whose density is to be determined.
According to the Archimedes’ principle, any object, wholly or partially immersed in a fluid, is buoyed up by
a force equal to the weight of the fluid displaced by the object.
Thevolume [ V ] of the glass sinker is same as the volume of the displaced liquid.
Buoyant force of the glass sinker = weight of the glass sinker in air [ A ] - weight of the glass sinker in the
measuring liquid [ B ]
That implies that:
    

= Density of the sample liquid
= Weight of the glass sinker in air
= Weight of the glass sinker in the measuring liquid
= Volume of the glass sinker
= Density of air (0.0012 g/cm3)
Influencing magnitudes and error sources
Air Pressure
Temperature
Volume deviation of the sinking object (± 0.005cm3)
Surface tension of the liquid
Air bubbles
Immersion depth of the sinking object
Porosity of the object
8Display information / Error messages
F----1 Date over display scope
F----2 A/D-switch disorder
F----3 Function key disorder
F----5 Sensor signal disorder /Load Cell defect
F----L Lower zero position of sensor signal
F----H Weighing capacity is exceeded
C----F Calibration error, instability or not at zero point during calibrating
C----H Calibration error, items on the pan or at higher zero point during calibrating