Logic II Series User manual

Installation Manual WTS3 Series II
M013610b.doc 1
LOAD CELL WEIGHT TRANSMITTER
MOD. WTS3
(SERIES II)
OPERATION AND INSTALLATION MANUAL
WTS3 load cell conditioner has been designed to meet the different weighing plants requirements.
Extremely simple installation and ease of use enable this instrument to be installed immediately
and effectively.
Its reliable and precise nature make it suitable for use in the most demanding conditions and
hence ideal for industrial applications.
Logic S.r.l.
Via del Tovo, 5/3
27020 Travacò Siccomario (PV)
WTS3-IIS ....................................
S.N. .......................................

Installation Manual WTS3 Series II
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WTS3 –GENERAL DESCRIPTION
WTS3 weight conditioner and transmitter has been developed to interface strain gage transducers
with industrial automation systems (such as PLC, computers etc..). The board supplies up to 4
load cell (350 ohm) amplifies the load cell signal and perform 2 different analog outputs: a 0 - 10 V
and a current output 0 - 20 mA or 4 - 20 mA (Factory selected).
The simple calibration procedure allow a quick set up and installation of the system.
The dead load compensation and full scale calibration is carried out by rotary switch for medium
setting and by trim-pots for fine setting.
The zero calibration of the analog output does not affect the full scale output and vice versa.
Calibrating the voltage output in the range 0 - 10 V, the current output is automatically calibrated.
The choice of the desired current range is carried out by a switch selection (standard range 4-20
mA) and correctly calibrating the device.
WTS3 conditioner is powered with 24 Vdc +/- 10 %.
Two different mounting versions are available :
- DIN rail mounting in plastic box (model WTS3).
- Boxed card in IP65 aluminium case for outdoor mounting (model WTS3-B).
GENERAL TECHNICAL SPECIFICATIONS
Load cells supply : 10 V
Max. current
:
170 mA (max. 6 x 350 ohm)
Input signal range
:
from 0.2 to 3.0 mV/V
Accuracy
:
0.1 % F.S.
Linearity
:
0.02 % F.S.
Thermal drift (full scale) : 0,005 % / °C F.S.
Thermal drift (zero)
:
0.005 % / °C F.S.
Operating temperature
:
from 0 °C to 45 °C
Analog outputs
:
0 - 10 V max 2mA
0 - 20 mA or 4 - 20 mA max 500 ohm
Filter
:
200 msec – 2 msec Selectable - low pass
Power supply
:
24 Vdc +/- 10 %
Power consumption
:
3 W max.
Board dimensions WTS3
:
23 x 99 x 112 (L x H x P)
Board dimensions WTS3-B
:
133 x 133 x 91 (L x H x P)

Installation Manual WTS3 Series II
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APPLICATION AND PRINCIPLE OF OPERATION
The module WTS3 is an amplifier for strain gage. This amplifier offers a simple and valid
procedure for calibration using rotary switches and trim-pots.
The supply voltage of the transducer is 10 Vdc with the possibility of connection to 4 or 6 wires.
With six-wire connection, making a correct compensation of the voltage drop on the connecting
cables, for a calibration easier and a higher accuracy.
The block diagram following from an indication of the structure of the conditioning module.
Note the simultaneous presence of voltage and current outputs 4-20mA ranges and 0-10 V. The
outputs and the power of the load cell are electrically isolated from the external 24 Vdc. This allows
the connection of several weighing systems to a data collection system (PLC or PC) using the
same power supply (+24 Vdc) shared with other devices without problems.
ELECTROMAGNETIC COMPATIBILITY (EMC)
WTS3 conditioner meets EEC 89/336 directive requirements.
Due to its plastic box it is sensible to radiated interferences generated by radio transmitters.
Installation suggestions :
•Use earthed shielded cables. To improve shielding efficiency, both sides of the cable shield can
be connected to earth. This is permitted when low values of earth resistance are detected.
•Install the board in a earthed metal box. If the board is placed into a metal cabinet with other
systems, further shields are not necessary.

Installation Manual WTS3 Series II
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SET UP :SWITCH SW3 SELECTION
SELECTION OF THE CURRENT RANGE
Select switch SW3-5 according to the following table to select the output current range 4 - 20 mA
or 0 - 20 mA :
SW3-5 Output signal range
ON
4 - 20 mA
OFF
0 - 20 mA
SELECTION OF ANALOG FILTER
The device provides for the possibility of choosing between two types of damping of mechanical
vibrations or electrical noise. Select the switch SW3-4 for the desired choice of the filtering of the
analog signal as shown in the following table :
SW3-4
Analog filter
ON
2 msec.
OFF
200 msec.
SELECTION OF COARSE AMPLIFICATION
It is possible choose from three fields of signal amplification of the load cells. Select the switch
SW3-1, 2, 3 for the choice of the desired range as indicated in the following table :
SW3-1
SW3-2
SW3-3
Input signal range
(Coarse amplification)
ON
OFF
OFF
From 0,4 to 3,1 mV/V of useful signal
OFF
ON
OFF
From 0,2 to 1,5 mV/V of useful signal
OFF
OFF
ON
Special version – Customer application
ATTENTION :
•Our technicians are available for any requests for customization of the card with
fields other than standard.
•SW3-6 : not used.

Installation Manual WTS3 Series II
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TERMINAL BOARD CONNECTIONS
POWER SUPPLY
Use a power cable, with suitable protection to the environment in which they are installed, with a
maximum section of 1.5 sqmm.
LOAD CELLS
Load cell output is a low level signal (few millivolts); then it is necessary to use a good quality
shielded cables.
A 4 or 6 wires twisted pairs 100% shielded cables is recommended. Refer to enclosed drawing to
match the cable twisted pair correctly.
CURRENT AND VOLTAGE OUTPUTS
Shielded cables should be used also for analog output connection to external devices.
The 0-10 Vdc and 4-20 mA outputs are galvanically isolated from the power supply (+24 Vdc and
negative Com24).
The negative output voltage (-Vout) is connected internally to the negative output current (-Iout).
Voltage and current outputs can be used at the same time to connect two different devices.
The current output is active and provides for a maximum load (impedance of the connected load)
of 500 ohms. This means that can also operate with an impedance of zero since the output is
virtually a current generator.
The output voltage is low power (voltage). Is allowed a maximum load of 2 mA (load impedance
equal to 5 Kohm) purely resistive.
The standard calibration range is from 0 to 10 V which corresponds to the 4-20 mA range
(calibration standard factory).
It is possible select the range 0-20 mA. In this case you must repeat the calibration procedure as
described later.

Installation Manual WTS3 Series II
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ELECTRICAL CONNECTIONS
Connect WTS3 as follows before to supply the board.
TB1-4 TB5-8 TB9-12 TB13-16
1
GND
5
+
V
OUT
9
S
HLD
13
-
E
XC
2
GND
6
-VOUT/-IOUT
10
-SIG
14
-S
3
+24 VDC
7
SHLD
11
+SIG
15
+S
4
COM24
8
+IOUT
12
SHLD
16
+EXC
Using cables and load cells LOGIC Srl refer to the following table the correspondence between the
color codes Logic and signals of the load cell.
SIGNAL
DESCRIPTION
EXTENSION CABLE
CAB-TS6
LOAD CELL
CABLE
+ Exc
+
E
XCITATION
Red
Red
-Exc
-EXCITATION
Blue
Black
+S
+SENSE
Green
--
- S
-SENSE
Grey
--
+ Sig
+SIGNAL
White
Green
-Sig
-SIGNAL
Yellow
White
Shld
SHIELD
Shield + Cont. Wire
Yellow / Shield

Installation Manual WTS3 Series II
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TRIM-POTS AND ROTARY SWITCH FUNCTION
SW1 : 16 position rotary switch for coarse span adjustment (10Vdc full scale).
P1 : Trim-pot for fine adjustment of span (full scale 10 Vdc).
SW2 : 16 position rotary switch for coarse zero adjustment (0Vdc).
P2 : Trim-pot for fine adjustment of zero (0 Vdc).
P3 : Trim-pot to set the beginning scale current (4 mA, calibrated at the factory).
P4 : Trim-pot to set full scale current (20 mA).
SW3 : 6 position dip-switch (see section on predisposition switches).

Installation Manual WTS3 Series II
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CALIBRATION PROCEDURE
If not otherwise specified, the device will come with the following setting range :
•Input : 0 - 2 mV/V
•Voltage output : 0 - 10 Vdc
•Current output : 4 - 20 mA
If you need a different range of calibration steps below.
After you have made and checked the connections steps follows :
•Open the plastic case by pressing on the locking tabs located near the terminals 2-3 and
14-15 as shown in Fig.
•Pull the board up to make accessible the trim-pots and switches to be operated, keeping
the attached cables (the cables connected to the terminals will be mobile enough).

Installation Manual WTS3 Series II
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RANGE CALIBRATION 0-10V and 4-20mA
•Connect a voltmeter to voltage output between + Vout e - Vout .
•Switch on the system and wait about 15 minutes for warm-up.
•Be sure the weighing system is completely empty.
•Rotate switch SW2 and trim-pot P2 to read the voltage output value to zero. For this
purpose use the lower range of the voltmeter.
•Load the weighing system with the full scale dead weight.
•Rotate switch SW1 and trim-pot P1 to exactly reach 10 V.
The system is now calibrated with the output voltage in the range 0 - 10 V and the current output in
the range 4 - 20 mA (SW3 = ON : factory setting).
RANGE CALIBRATION 0-10V and 0-20mA
If you need to use the 0 - 20 mA steps follows :
•Select switch SW3 = OFF on board.
•Follow the steps described in 6 points to the paragraph from the previous section.
•Connect then the amp-meter to -Iout +Iout.
•Load the scale with full scale weight and rotate the trim-pot P4 up to 20mA reading on the
measuring instrument.
The system is now calibrated with the output voltage in the range 0 - 10 V and the current output in
the range 0 - 20 mA.
ATTENTION :
If it is not possible to arrange the exact value corresponding to the full scale, use a dead weight
greater than 50 % (at least) of full scale value and calibrate the voltage output with the calculated
value as shown below :
dead weight : X = full scale value : 10 V
where X = voltage to read on the voltmeter with the dead weight on the scale.
Example :
full scale
= 2000 Kg
dead weight
= 1250 Kg
1250 x 10
X = —————— = 6.25 V
2000
In this case with a dead weight of 1250 Kg the voltage output should be regulated to 6.25 V.

Installation Manual WTS3 Series II
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MECHANICAL DIMENSIONS WTS3
MECHANICAL DIMENSIONS WTS3-B
PG13,5
PG9
TERMINAL BOARD CABLES CONNECTION
WEIGHT TRANSMITTER WTS3 SERIES
Max. Current : 0,15 A
Power Supply : 24 Vdc Load Cells Supply : 10 Vdc
Max. Load Cells : 4 x 350 ohm
LOGIC Srl - Via del Tovo 5/3
Travaco' Siccomario (PV)
www.logic-pavia.it
91
115
100
133
133
25

Installation Manual WTS3 Series II
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DICHIARAZIONE DI CONFORMITA’
DECLARATION OF CONFORMITY
Marcatura CE
CE Mark
NOME DEL FABBRICANTE : LOGIC s.r.l.
Name of manufacturer :
INDIRIZZO DEL FABBRICANTE : Via del Tovo 5/3 - Travacò Siccomario - PAVIA
Address of manufacturer :
DICHIARA CHE IL PRODOTTO
DECLARES THAT THE PRODUCT
MODELLO : SERIE WTS3
Model : WTS3 Series
DESCRIZIONE DELL’APPARATO : Condizionatore per celle di carico per installazione in quadri
elettrici industriali.
Apparatous description : Load cells conditioner for industrial electrical cabinet
installations.
SODDISFA LE DISPOSIZIONI DELLA DIRETTIVA 89/336/CEE DEL 3MAGGIO 1989 E SUCCESSIVE
MODIFICHE
Meet requirements of directive 89/336/EEC of may 3 1989 and subsequent modifications
L’APPARATO ELETTRONICO IN OGGETTO E’STATO TESTATO SECONDO GLI STANDARD ARMONIZZATI DI
SEGUITO ELENCATI.
This electronic apparatous is tested according to following harmonised standard.
EN 55011
EN 61000-4-3
EN 61000-4-8
EN 61000-4-2
EN 61000-4-6
EN 61000-4-4
PAVIA
,
12-09-2007
Giulio Menini
Presidente/President