HBM WE2108 Series User manual

WE2108S
WE2108M
WE2108
A1632-2.0 en
Scale electronic unit
(NAWI)
WE2108...
(P83...P85)
Reference Manual

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HBMA1632-2.0 en
Content Page
Safety instructions 7..............................................
1 Typographic Conventions 11.................................
2 Commissioning 12..........................................
2.1 Notes on cabling 12..........................................
3 Short description 13.........................................
3.1 Scope of supply 13...........................................
3.1.1 WE2108 unit view 14.........................................
3.1.2 Operating elements 14........................................
3.1.3 Display 15...................................................
3.2 Connections 16..............................................
3.2.1 Cable entry 17...............................................
3.2.2 Preparation of the cables 17...................................
3.2.3 Load cell connection 17.......................................
3.2.4 Process Outputs 18..........................................
3.2.5 WE2108 operating voltage 18..................................
3.2.6 Process Inputs 18............................................
3.2.7 RS−232 interface (only RS−232 versions) 19....................
3.2.8 RS−485 interface (only RS−485 versions) 19....................
3.2.9 Remarks 19.................................................
4 Installation 20...............................................
4.1 Wall mounting (WE2108 in a plastic housing) 20..................
4.2 Mounting on a stand (WE2108 in a plastic housing) 21............
4.3 Use as desktop unit (WE2108 in a plastic housing) 22.............
4.4 Wall mounting / desktop unit (WE2108S in a stainless steel housing) . .
22
4.5 Control panel assembly (WE2108M in a stainless steel housing) 22.
4.6 Sealing / calibration ability 23..................................
4.7 Information on achievable type of protection 23...................
5 Operation 24................................................
5.1 Basic functions 25............................................
5.1.1 Switching on and off 25.......................................

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5.1.2 Zeroing () 25................................................
5.1.3 Taring () 26..................................................
5.1.4 Gross/Net () 26..............................................
5.1.5 Printing () 26................................................
5.1.6 Preset tare 26...............................................
5.1.7 Display lighting 27...........................................
5.1.8 External operating elements 27................................
5.1.9 Counting scale () 27..........................................
5.1.10 Parameter setting 28.........................................
5.1.11 Error displays 29............................................
5.1.12 Stillstand 29.................................................
5.2 Menu operation 30...........................................
5.2.1 Menu Overview 30...........................................
5.2.2 Example: Setting the parameter ”CAP 1” 32.....................
5.2.3 Complete menu structure 33..................................
5.3 Explanations for the settings 39................................
5.3.1 Display limits 39.............................................
5.3.2 Tare value 39................................................
5.3.3 Standstill criterion 41.........................................
6 Calibration 42...............................................
6.1 Quick start without special functions 42.........................
6.1.1 Setting to the nominal data of the scale 42.......................
6.1.2 Calibration (standard method) 42...............................
6.1.3 Part load calibration 43.......................................
6.1.4 Setting for legal for trade 43...................................
6.2 Special applications 44.......................................
6.3 Calibration with linearization 45................................
6.3.1 Selection of the calibration method with the ”Lin” parameter 45.....
6.3.2 Calibration steps for linearization (3 or 4 points) 45...............
6.4 Direct entry of the characteristic values 47.......................
6.4.1 Calibrating with calculated values 48............................
6.5 Influence of the geographical installation site 49..................
6.6 Access authorization 50.......................................
6.6.1 Pushbutton lock 51...........................................
6.7 Selection of suitable load cells 51..............................

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6.7.1 Division number: 51..........................................
6.7.2 Supply voltage and measuring signal: 51........................
6.7.3 Dead load and nominal value: 52...............................
7 Further functions 53.........................................
7.1 Filtering 53..................................................
7.1.1 Filter and standstill 53........................................
7.1.2 Special filter for animal scales 53...............................
7.2 Limit outputs 54..............................................
7.3 Inputs 55....................................................
7.4 Printing function 57...........................................
7.5 Formatting of the printing output 58.............................
7.5.1 Example 59.................................................
7.6 Setting the time 59...........................................
7.7 Summing function 59.........................................
7.7.1 Overview 59.................................................
7.7.2 Functions in the menu Add (new) 60............................
7.7.3 Permitted range 60...........................................
7.7.4 Deletion of the sums 61.......................................
7.7.5 Summing function during counting scale operation 61.............
7.7.6 Print 62.....................................................
7.8 Interface for large display (second display) 63....................
8 Troubleshooting 64..........................................
9 Specifications 66............................................
9.1 Specifications WE2108 in ABS−housing 66......................
9.2 Dimensions WE2108 in ABS−housing 67........................
9.3 Specifications WE2108S/WE2108M in steel−housing 68..........
9.4 Dimensions WE2108S/WE2108M in steel−housing 69............

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Safety instructions
In cases where a breakage would cause injury to persons or damage to
equipment, the user must take appropriate safety measures (such as fall pro-
tection, overload protection, etc.). For safe and trouble−free operation, weigh-
ing modules must not only be correctly transported, stored, sited and installed
but must also be carefully operated and maintained.
It is essential to comply with the relevant accident prevention regulations. In
particular you should take into account the limit loads quoted in the specifica-
tions.
Functional overview
The scale electronic unit WE2108 is a measuring amplifier for connection to
commercially available strain gauge load cells or scales. The load cell signal
is amplified and digitally converted, all further processing steps are performed
digitally in a microprocessor.
The electronic unit is set and parameterized via keyboard or interface. The
setup program WE2108Panel serves for this purpose.
It is contained together with this documentation on the HBM CD−ROM with
the Order No. 1−WE2108/DOC.
Use in accordance with the regulations
The scale electronic unit WE2108 is to be used exclusively as component of a
non−automatic scale. Any use extending beyond this is considered to be not
as intended.
In the case of legal for trade use, the national legal and safety regulations
must be complied with.
General dangers due to non−observance of the safety instructions
•In the normal case the product causes no dangers, provided the notes and
instructions for configuring, installation, operation as intended and mainte-
nance are complied with.
•The safety and accident prevention regulations applicable corresponding to
the application must be observed without fail.
•Installation and commissioning may be performed exclusively by qualified
personnel.
•Avoid the penetration of dirt and moisture into the interior of the unit when
connecting the cables.
•When connecting the cables take measures against electrostatic dis-
charges which can damage the electronic unit.

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HBM A1632-2.0 en
•An extra low voltage (10 − 35 V) with safe isolation from the mains is
required for the power supply of the unit.
•When connecting additional devices, the safety regulations according to
EN610101) must be complied with.
•Observe the maximum voltage level when connecting external control sys-
tems to the process input and process outputs of the WE2108.
•The ground connections of the supply, of the process inputs and process
outputs, of the interface and the shield of the load cell cable are connected
with one another in the unit. In the case of potential differences of the
devices to be connected, isolate the signals in a suitable manner (e.g. by
optocoupler).
•Shielded cables are required for all connections, except for power supply.
The shield must be connected flatly with ground at both ends.
•The use of unscreened voltage supply cables is permissible only for cables
with a length of up to 30 m max., which are laid within a building. In the
case of greater cable lengths, or installation outside buildings, a screened
cable must be used. In order to compensate for potential differences, the
metal housing of WE2108M / WE2108S has to be connected via a low
ohmic compensation conductor with the scale components as well as with
the ground potential of the connected units. This is not necessary if a poten-
tial difference of 35 V is not exceeded.
In the unit, the reference ground (GND) for all signals and the supply volt-
age is connected directly to the cable screen connection, but not to the
housing.
•The front foil is manufactured from high quality materials and offers a ser-
vice life appropriate for the external conditions. The keys may be operated
only by hand, under no circumstances may pointed objects be used to
press the keys.
!) ”Safety regulations for electrical measuring, control and laboratory equipment“
Residual dangers
The scope of supply and performance of the scale electronic unit covers only
a small area of weighing technology. In addition, equipment planners, install-
ers and operators should plan, implement and respond to the safety engineer-
ing considerations of weighing technology in such a way as to minimise resid-
ual dangers. Prevailing regulations must be complied with at all times. There
must be reference to the residual dangers connected with weighing technol-
ogy.

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HBMA1632-2.0 en
In these mounting instructions residual dangers are pointed out using the fol-
lowing symbols:
Symbol: DANGER
Meaning: Highest level of danger
Warns of a directly dangerous situation in which failure to comply with safety
requirements will lead to death or serious physical injury.
Symbol: WARNING
Meaning: Possibly dangerous situation
Warns of a potentially dangerous situation in which failure to comply with
safety requirements can lead to death or serious physical injury.
Symbol: ATTENTION
Meaning: Possibly dangerous situation
Warns of a potentially dangerous situation in which failure to comply with
safety requirements could lead to damage to property, slight or moderate
physical injury.
Symbols indicating application notes and useful information:
Symbol: NOTE
Refers to the fact that important information is being given about the product
or its use.
Symbol:
Meaning: CE mark
The CE mark signals a guarantee by the manufacturer that his product meets
the requirements of the relevant EC directives. You’ll find the Declaration of
conformity in the up-to-date version of HBMdoc, available at www.hbm.com :
•Choose your country
•SUPPORT
•Documentation

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HBM A1632-2.0 en
Environmental conditions
In the context of your application, please note that all materials which release
chlorine ions will attack all grades of stainless steel and their welding seams.
In such cases the operator must take appropriate safety measures.
Prohibition of own conversions and modifications
The scale electronic unit must not be modified from the design or safety engi-
neering point of view except with our express agreement. Any modification
shall exclude all liability on our part for any damage resulting therefrom.
Qualified personnel
This weighing electronic is only to be installed by qualified personnel strictly in
accordance with the technical data and with the safety rules and regulations
which follow. It is also essential to observe the appropriate legal and safety
regulations for the application concerned. The same applies to the use of
accessories.
Qualified personnel means persons entrusted with the installation, fitting,
commissioning and operation of the product who possess the appropriate
qualifications for their function.
Maintenance and cleaning
The WE2108 is maintenance−free. Observe the following points when clean-
ing the housing:
•Separate the connection to the power supply before cleaning.
•Clean the housing with a soft, slightly moistened (not wet!) cloth. Under no
circumstances may you use cleaners containing scouring agents or sol-
vents, since these can attack the front panel lettering and the display!

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1 Typographic Conventions
The present Reference Manual provides detailed information on the operation
as well as on the setting possibilities of the WE2108.
For more clarity the following formats are used in this document:
Meaning Examples
Key ENTER
UP
CE
NEXT
Menu, Sub−Menu InFO
CAL or
Fun
Parameter ”CAL−1”
”LOAd1”
”unit”
”Point”
Display DonE
BuSY
Err44

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2 Commissioning
The permissible supply voltage for the WE2108 is in the range from
+10...35 V DC and must be filtered sufficiently (rms value less residual ripple
> 10 V).
As an accessory component, a power supply unit 100 ... 240 V is available
(HBM order no. 1−AC/DC15V/550mA).
With correct connection with shielded cables the WE2108 corresponds to the
relevant European standards and bears the CE mark.
2.1 Notes on cabling
The use of unscreened voltage supply cables is permissible only for cables
with a length of up to 30 m max., which are laid within a building. In the case
of greater cable lengths, or installation outside buildings, a screened cable
must be used.
In order to compensate for potential differences, the metal housing of
WE2108s and WE2108M has to be connected via a low ohmic compensation
conductor with the scale components as well as with the ground potential of
the connected units. This is not necessary if a potential difference of 35 V is
not exceeded.
In the unit, the reference ground (GND) for all signals and the supply voltage
is connected directly to the cable screen connection, but not to the housing.

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HBMA1632-2.0 en
3 Short description
3.1 Scope of supply
The original packaging contains:
WE2108:
•Scale electronic unit WE2108 (ABS housing) with four PG glands
•2 countersunk head screws + wall plugs for wall mounting
•Adhesive mark for closing and sealing the opening for calibration button
and lettering strips
•6 lettering strips for calibration data
WE2108M:
•Scale electronic unit WE2108M... (Panel mounting) with 5 grommets
•Adhesive mark for closing and sealing the opening for calibration button
and lettering strips
•6 lettering strips for calibration data
WE2108S:
•Scale electronic unit WE2108S... (Stainless steel housing)
•2 countersunk head screws + wall plugs for wall mounting
•Adhesive mark for closing and sealing the opening for calibration button
and lettering strips
•6 lettering strips for calibration data
The CD−ROM available as accessory with the Order No. 1−WE2108/DOC
contains apart from the complete documentation (Reference Manual) of the
unit also the setup program WE2108Panel. This PC software serves for mea-
sured value display and configuration of the WE2108 through the serial inter-
face.

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HBM A1632-2.0 en
3.1.1 WE2108 unit view
The front of the WE2108 consists of the following elements:
ENTER UP
CE NEXT
WE2108
1.
3.
4.
2.
0
G/N T
MENU
1.Display window with 5−digit numerical display and special symbols.
2.Keys for scale and menu functions.
3.Concealed button for access to the calibration menu. The button is accessi-
ble with a pointed object (with the mark removed). The opening must be
closed after calibration with the enclosed adhesive mark or in the case of a
legal for trade application with the official calibration mark. In operation the
calibration of the unit is protected and can be changed only after actuating
this button.
Please also refer to Sections 4.7 ”Information on achievable type of protec-
tion” and 6.6 ”Access authorization”.
4.Viewing window for inserting a lettering strip (for calibration data, unit name
etc.).
The PG glands resp. grommets for the connection cables are located on the
back of the unit.
3.1.2 Operating elements
Each of the four keys has a basic function for scale operation which is indi-
cated on the key with a large symbol.
•Key
0
= Zeroing the display
•Key = Printing the display measured value / or summing function
•Key
G/N
= Switching over between gross and net display
•Key
T
= Taring and switching over into net display

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The inscriptions above the keys state the second function of the keys during
parameter input (menu guidance).
Activating the functions
MEN
U
:simultaneously pressing of ENTER )UP
(Counting scale): simultaneously pressing of CE )NEXT
•Concealed button for access to the calibration menu (see WE2108 unit
view).
3.1.3 Display
The display consists of the following elements:
•5−digit numerical display with decimal points for the weight value
and for menu guidance in the parameter input.
•Symbol (= Battery): appears if the supply voltage is inadmissibly low.
•Symbols 1 and 2.: Their meaning depends upon the scale type.
One−range scale: Symbol shows exceeding the set limit 1 or 2.
Two−range scale: Symbol shows the range at present valid.
The symbols have a further special function during parameter setting (see
Section 5.2.1 ”Menu Overview”)
•Symbol Hold : only for filter 8 (see Section 6.1.2 ”Special filter for animal
scales”)
•Symbol.Tare.: appears on display of the net value (simultaneously with
Net).
•Symbol "0A(”exact zero”): indicates that the measured value is in the range
of "¼ d.
•Symbol.Net : appears on display of the net value.
•Symbol PT.(Preset Tare): appears if a stored manual tare value is used.
•Symbols g, kg, t, Lb : indicate the valid dimensional unit.

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3.2 Connections
The load cell and all control and supply cables are connected by means of
screw terminals inside the housing. The terminals are equipped with wire pro-
tection, the use of connector sleeves is recommended especially for the load
cell cables.
The connection terminals are identified on the PC board with short text or
numbers.
NOTE
All ground connections are connected with one another on the PC board!
1.
2.
3.
4.
5.
6.
Pout3
GND
Pout2
GND
Pout1
GND
+DC
GND
Pin1
GND
Pin2
GND
GND
Ta TxD
Tb DTR Data Terminal Ready
Ra RxD
Rb
GND
Load cell connection
Process outputs
Process inputs
Supply
Interface
Sense +
Sense −
Signal +
Signal −
Excitation +
Excitation −
not used
Ground
Process output 2
Ground
Process output 1
Ground
Supply voltage
Ground
Process input 1
Ground
Process input 2
Ground
Ground
Ground
not used
Data output to ext. unit
Data input from ext. unit
Abb.3.1: Position of the connections (open housing, rear view)

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3.2.1 Cable entry
Four PG glands are provided in the back part of the housing for the sealed
entry of the cables. They enable round cables with a diameter of 5 to 7 mm to
be used. The PG glands serve solely for sealing and strain relief. The shield
of the cable must therefore not be contacted to the PG gland (as in other HBM
units), but to the screw clips in front of the connection terminals.
This also applies to the versions in a steel housing (WE2108M /
WE2108S) and is essential for the EMC characteristics of the units.
To minimize EMC problems, the individual wires should be as short as possi-
ble from the end of the shield up to the terminal. Therefore avoid cross−con-
nections, e.g. from the interface cable to a switching input, and use instead of
this separate cables corresponding to the terminal arrangement. A common
cable should be used for supply and switching inputs.
3.2.2 Preparation of the cables
1.Remove the outer sheath to around 20 mm.
2.Shorten the shield braiding to 5 mm and
fold over to the back.
3.If necessary remove the inner sheath.
4.Strip wire ends to approx. 5 mm.
5 5
Shield
20
5.Run cable through the PG gland.
6.Push cable under the connecting clip and screw this down so that the area
of the folded over shield is clamped firmly.
7.Connect wires to the terminals.
3.2.3 Load cell connection
Terminal PC board legend Function Funktion
1 1. Sense + Fühlerleitung +
2−− Sense − Fühlerleitung −
3−− Signal + Messsignal +
4−− Signal − Messsignal −
5−− Excitation + Brückenspeisespannung +
6 6. Excitation − Brückenspeisespannung −

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3.2.4 Process Outputs
Terminal PC board legend Function Example of connection
7 Pout3 not used
Pout3
GND
Pout2
GND
Pout1
GND
Supply for
switched loads
+
−
8 GND Ground
9 Pout2 Process output 2!)
10 GND Ground
11 Pout1 Process output 1!)
12 GND Ground
!)open−collector to ground, (external) Umax = 45 V, Imax = 200 mA typ. (electronically protected). When con-
necting magnetic articles (e.g. relays), a free wheeling diode must be connected parallel to the coil.
3.2.5 WE2108 operating voltage
Terminal PC board legend Function Remarks
13 +DC Operating voltage +10−35 V DC@)
14 GND Ground
@)The supply voltage must be filtered sufficiently (rms value less residual ripple > 10V).
3.2.6 Process Inputs
Terminal PC board legend Function Example of connection
15 Pin1 Process input 1#)+DC
GND
Pin1
GND
Pin2
GND
16 GND Ground
17 Pin2 Process input 2#)
18 GND Ground
#)Actuate by switching to ground, max. voltage 35 V.

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3.2.7 RS−232 interface (only RS−232 versions)
Terminal PC board legend Function Standard assignment
of external unit
RS−232 DB25 RS−232 DB9
19 GND Ground Pin7 Pin5
20 Ta TxD Data output to the
external unit (TxD) RxD, Pin3 RxD, Pin2
21 Tb DTR do not connect !
22 Ra RxD Data input from the
external unit (RxD) TxD, Pin2 TxD, Pin3
23 Rb do not connect !
24 GND Ground
TxD TxD
RxD RxD
GND GND
For the communication with an external device its TxD line must be
connected with RxD of the WE2108 and vice versa.
3.2.8 RS−485 interface (only RS−485 versions)
See Reference Manual Part 2 (Description of the commands for computer
integration)
3.2.9 Remarks
For all housing variants, the reference ground (GND) for all signals and
the supply voltage is connected directly to the cable screen connection
in the unit, but not to the housing.
The metal housing of WE2108M / WE2108S is not connected to reference
ground. In order to compensate for potential differences, the metal
housing of WE2108s and WE2108M has to be connected via a low ohmic
compensation conductor with the scale components as well as with the
ground potential of the connected units. This is not necessary if a
potential difference of 35 V is not exceeded.
Up to four load cells of 350 ohms (w87 ohms burden) can be connected to
the WE2108. HBM offers junction boxes of the types VKK1−4 or VKK2−6 for
connecting the cables as well as for corner balancing (”corner load adjust-
ment”) for scales with several load cells.
Only high quality, flexible cables with shield may be used for connecting the
load cells. HBM recommends the use of these cables for all connections of
the WE2108. For connection satisfying EMC requirements (EMC = electro-
magnetic compatibility), the cable shield of all cables must have a low−resis-
tance contact to the unit ground, for this purpose the shield must be stripped
to approx. 5 mm and the cable must be fastened with the strain relief clips.

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HBM A1632-2.0 en
Electrical and magnetic fields frequently cause coupling of interference volt-
ages into the measuring circuit. Use only shielded, low−capacitance measur-
ing cables (measuring cables from HBM fulfil these conditions). Do not run the
measuring cables parallel to power current and control cables. If this is not
possible, protect the measuring cable (e.g. by steel conduits). Avoid stray
fields of transformers, motors and contactors.
The WE2108 is designed for six−wire connection of the load cell. When con-
necting four−wire load cells, in each case connect the terminals 1 with 5 and
2 with 6 using cable jumpers. In the case of faulty load cell connection or
leaving the sensor lines open (terminal 1 and 2) the message Err44 appears
on the display.
4 Installation
4.1 Wall mounting (WE2108 in a plastic housing)
The housing design of the WE2108 permits wall mounting without visible
mounting elements. For this purpose the finally assembled unit must be set
against the wall and snapped in as in Abb. 4.2 Since the wall screws are not
visible in this case, the mounting base of the housing has lead−in bevels for
tactile determination of the screw position.
Two screws are required (countersunk head screws in the scope of supply) at
a spacing of 86 mm. In this type of mounting the housing is secured against
lifting off by forces occurring in everyday use by the screws snapping in.
A prerequisite is the use of one of the following types of screw:
•Cheese−head screws, shank without thread with 4 mm diameter.
•Countersunk head screws, diameter under the head max. 3.5 mm. For
mounting with wall plugs, 4.0 x 50 mm chipboard screws, the thread of
which ends approx. 10 mm under the head, for instance, are suitable.
Please observe the correct distance of the screw heads from the wall (in mm):
or
86
8
9
left + rightleft right
7
Wall
Abb. 4.1: Distances