Rice Lake SCT-10 User Manual

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SCT Weight Transmitter

10 Series

Installation & Operator’s Manual

131129 Rev A

Technical training seminars are available through Rice Lake Weighing Systems.

Course descriptions and dates can be viewed at www.ricelake.com/training

or obtained by calling 715-234-9171 and asking for the training department.

1.0 Introduction............................................................................ 1

1.1 Safety. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1.1 Safety Symbol Definitions: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1.2 Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1.3 Equipment Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.1.4 Correct Installation Of Weighing Instruments . . . . . . . . . . . . . . . . . . . 2

1.1.5 Correct Installation Of The Load Cells. . . . . . . . . . . . . . . . . . . . . . . . . 2

1.2 Load Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.2.1 Load Cell Input Test (Quick Access) . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.2.2 Load Cell Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

1.3 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

1.4 Electrical Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

1.5 LED and Key Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

1.6 Instrument Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

1.6.1 If The Instrument Has Not Been Calibrated. . . . . . . . . . . . . . . . . . . . . 8

2.0 Configuration ......................................................................... 9

2.1 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

2.1.1 Theoretical Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2.1.2 Maximum Capacity (NASS ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2.1.3 Zero Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.1.4 Zero Value Manual Entry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.1.5 Weight (Span) Calibration (With Test Weights) . . . . . . . . . . . . . . . . . 16

2.1.6 Setting Units of Measure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

2.1.7 Display Coefficient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

2.2 Filter On The Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.3 Zero Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2.4 Analog Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.5 Serial Communication Settings . . . . . . . . . . . . . . . . . . . . . . . 23

2.5.1 RS-485 Serial Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.6 Outputs And Inputs Configuration . . . . . . . . . . . . . . . . . . . . . 26

2.7 Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

2.8 Setpoints Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

2.9 Reserved For The Installer . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

2.9.1 Default Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

2.9.2 Program Selection - Reverse:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

2.9.3 Keypad Or Display Locking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Specifications subject to change without notice.

Rice Lake Weighing Systems is an ISO 9001 registered company.

December 27, 2013

Rice Lake continually offers web-based video training on a growing selection

of product-related topics at no cost. Visit www.ricelake.com/webinars.

3.0 Operation.............................................................................. 32

3.1 Semi-Automatic Tare (Net/Gross) . . . . . . . . . . . . . . . . . . . . . 32

3.2 Preset Tare (Subtractive Tare Device) . . . . . . . . . . . . . . . . . . 32

3.3 Semi-Automatic Zero (Weight Zero-setting For Small Variations) 33

3.4 Peak. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

3.5 Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

3.6 Modbus-RTU Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

3.7 ASCII Bidirectional Protocol. . . . . . . . . . . . . . . . . . . . . . . . . . 41

3.8 Fast Continuous Transmission Protocol . . . . . . . . . . . . . . . . 46

3.9 Continuous Transmission Protocol To Remote Displays . . . 46

3.10 Communication Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 48

SCT Weight Transmitter Limited Warranty ................................... 51

For More Information .................................................................... 53

ii SCT Weight Transmitter Operator’s Manual

1.0 Introduction

WARNING

Important

WARNING

1.1 Safety

1.1.1 Safety Symbol Definitions:

Indicates a potentially hazardous situation that, if not avoided could result in death or serious injury, and includes hazards that are exposed when guards are removed.

Indicates information about procedures that, if not observed, could result in damage to equipment or corruption to and loss of data.

1.1.2 Safety Precautions

Do not operate or work on this equipment unless you have read and understand the instructions and warnings in this manual. Contact any Rice Lake Weighing System dealer for replacement manuals. Proper care is your responsibility.

Failure to heed may result in serious injury or death.

Risk of electrical shock. No user serviceable parts. Refer to qualified service personnel for service.

The unit has no power switch, to completely remove D/C power from the unit, disconnect the D/C power cable from the main socket.

DO NOT allow minors (children) or inexperienced persons to operate this unit.

DO NOT operate without all shields and guards in place.

DO NOT use for purposes other then weighing applications.

DO NOT place fingers into slots or possible pinch points.

DO NOT use this product if any of the components are cracked.

DO NOT make alterations or modifications to the unit.

DO NOT remove or obscure warning labels.

DO NOT use near water.

Introduction 1

1.1.3 Equipment Recommendations

Important

Failure to follow the installation recommendations will be considered a misuse of the equipment

To Avoid Equipment Damage

• Keep away from heat sources and direct sunlight.

• Protect the instrument from rain.

• Do not wash, dip in water or spill liquid on the instrument.

• Do not use solvents to clean the instrument.

• Do not install in areas subject to explosion hazard.

1.1.4 Correct Installation Of Weighing Instruments

• The terminals indicated on the instrument’s wiring diagram to be connected to earth must have the same potential as the scale structure (ground). If you are unable to ensure this condition, connect a ground wire between the instrument and the scale structure.

• The load cell cable must be run separately to the instrument input and not share a conduit with other cables. A shielded connection must be continuous without a splice.

• Use “RC” filters (quench-arcs) on the instrument-driven solenoid valve and remote control switch coils.

• Avoid electrical noise in the instrument panel; if inevitable, use special filters or sheet metal partitions to isolate.

• The panel installer must provide electrical protection for the instruments (fuses, door lock switch, etc.).

• It is advisable to leave equipment always switched on to prevent the formation of condensation.

• Maximum Cable Lengths:

- RS-485: 1000 metres with AWG24, shielded and twisted cables

- RS-232: 15 metres for baud rates up to 19200

1.1.5 Correct Installation Of The Load Cells

Installing Load Cells:

The load cells must be placed on rigid, stable structures within .5% of plumb and level. It is important to use mounting modules for load cells to compensate for misalignment of the support surfaces.

Protection Of The Load Cell Cable:

Use water-proof sheaths and joints in order to protect the cables of the load cells.

Mechanical Restraints (pipes, etc.):

When pipes are present, we recommend the use of hoses, flexible couplings and rubber skirted joints. In case of rigid conduit and pipes, place the pipe support or anchor bracket as far as possible from the weighed structure (at a distance at least 40 times the diameter of the pipe).

Welding:

Avoid welding with the load cells already installed. If this cannot be avoided, place the welder ground clamp close to the required welding point to prevent sending current through the load cell body.

2 SCT Weight Transmitter Operator’s Manual

Windy Conditions - Shocks - Vibrations:

Uses ground plate

to continue ground.

Uses structure to continue ground.

ESC

The use of weigh modules is strongly recommended for all load cells to compensate for misalignment of the support surfaces. The system designer must ensure that the scale is protected against lateral shifting and tipping relating to shocks and vibration, windy conditions, seismic conditions and stability of the support structure.

Grounding The Weighed Structure:

By means of a 10ga solid or braided wire or braided grounding strap, connect the load cell upper support plate with the lower support plate, then connect all the lower plates to a single earth ground. Once installed electrostatic charges accumulated are discharged to the ground without going through or damaging the load cells. Failure to implement a proper grounding system might not affect the operation of the weighing system; this, however, does not rule out the possibility that the load cells and connected instrument may become damaged by ESD. It is forbidden to ensure grounding system continuity by using metal parts contained in the weighed structure.(see Figure 1-1.)

1.2 Load Cells

1.2.1 Load Cell Input Test (Quick Access)

1. From the weight display, press for 3 seconds.

2. The display will read NU-CEL. Press .

3. The response signal of the load cell is displayed, expressed in mV with

four decimals. Press three times to exit set-up mode.

Figure 1-1. Installation Recommendations

Introduction 3

1.2.2 Load Cell Testing

Important

ANALOG OUTPUT

(Current and Voltage)

PLC

PLC or FIELD SIGNALS

2 DIGITAL INPUTS

(Optoisolated, Externally supplied)

2 RELAY

MAX 8 LOAD CELLS IN

PARALLEL

RS-485 RS-232 Modbus RTU

SERIAL PORT

DC power

supplier

(12-24 Volt )

Load Cell Resistance Measurement (Use A Digital Multimeter):

• Disconnect the load cells from the instrument and check that there is no moisture in the load cell junction box caused by condensation or water infiltration. If so, drain the system or replace it if necessary.

• The value between the positive signal wire and the negative signal wire must be equal or similar to the one indicated in the load cell data sheet (output resistance).

• The value between the positive excitation wire and the negative excitation wire must be equal or similar to the one indicated in the load cell data sheet (input resistance).

• The insulation value between the shield and any other load cell wire and between any other load cell wire and the body of the load cell must be higher than 20 Mohm (mega ohms).

Load Cell Voltage Measurement (Use A Digital Multimeter):

• Remove weight of scale from load cell to be tested.

• Make sure that the excitation wires of the load cell connected to the instrument is 5 Vdc +/- 3%.

• Measure the millivolt signal between the positive and the negative signal wires by directly connecting them to the multi-meter, and make sure it reads between 0 and 0.5 mV (thousandths of a Volt).

• Apply load to the load cell and make sure that there is a signal increment.

If one of the above conditions is not met, please contact the technical assistance service.

1.3 Specifications

• Weight indicator and transmitter for Omega/DIN rail mounting suitable for back panel; space saving vertical shape. Six-digit semi alphanumeric display (18mm h), 7 segment. Four-key keyboard. Dimensions: 25x115x120 mm.

• Displays the gross weight; with an external contact capable of remote zeroing and gross/net switching.

• IP67 box version (dimensions: 170x140x95mm). Four fixing holes diameter 4mm (center distance 122x152mm).

• Peak weight function.

4 SCT Weight Transmitter Operator’s Manual

• Transmits the gross or net weight via opto-isolated analog output 16 bit, current 0-20mA, 4-20mA or voltage 0-10V, 0-5V (±0V / ±5V by closing a soldered jumper).

• Transmits the gross or net weight via RS-485 serial port, by means of protocols:

- Modbus RTU

- ASCII bidirectional protocol

- Continuous transmission

Power Supply And Consumption (VDC) 12 - 24 VDC (standard)+/- 10% ; 5 W No. Of Load Cells In Parallel and

Supply Linearity / Analog Output Linearity < 0.01% F.S. ; < 0.01% F.S. Thermal Drift / Analog Output Thermal

Drift A/D Converter 24 bit (16.000.000 points) Max Divisions (With Measurement

Range: +/-10mv = Sens. 2mv/v) Measurement Range +/- 19.5 mV Max Sensitivity Of Usable Load Cells +/-3mV/V Max Conversions Per Second 80 conversions/second Display Range - 999999 ; + 999999 No. of Decimals / Display Increments 0 - 4 / x 1 x 2 x 5 x 10 x 20 x 50 x 100 Digital Filter / Readings Per Second 0.080 – 7.5 sec / 5 - 80 Hz Relay Logic Outputs N.2 - max 24 VAC ; 60mA Logic Inputs N.2 - optoisolated 5 - 24 VDC PNP Serial Ports RS-485 (RS-232) Baud Rate 2400, 4800, 9600, 19200, 38400,

Humidity (Non Condensing) 85 % Storage Temperature - 30°C + 80°C Working Temperature - 20°C + 60°C Optoisolated Analog Output 16 Bit -

65535 Divisions

max 8 ( 350 ohm ) ; 5VDC/120mA

< 0.0005 % F.S. /°C ; < 0.003 % F.S./°C

+/- 999999

115200

0-20 mA; 4-20 mA (max 300 ohm); 0-10 VDC; 0-5 VDC; +/- 10 VDC; +/- 5 VDC (min 10 kohm).

Table 1-1. Technical Specifications

Introduction 5

1.4 Electrical Connections

13123456789 111210

141516 17 18 19 20

LOAD CELLS IN PARALLEL

IN1

IN2

IN COM

OUT1

OUT2

+ RS485

RS485

mA-V COM

NET 0

INPUTS 5-24Vdc

OUTPUTS

24Vdc

60mA

RS485

OUTPUT

12-24Vdc

ANALOG

RS485 termination

ESC

333130 322827252324 26 2922 34

+ 12-24

0 VDC

POWER

+ EX

SIG

+ SIG

+ EX

SIG

+ SIG

+ EX

SIG

+ SIG

+ EX

SIG

+ SIG

SCT

Current output: max load 300 Ohm Voltage output: min. load 10 kOhm

- EXCITATION

+ EXCITATION

- SIGNAL

+ SIGNAL

- EXCITATION

+ EXCITATION

- SIGNAL

+ SIGNAL

- EXCITATION

+ EXCITATION

- SIGNAL

+ SIGNAL

- EXCITATION

+ EXCITATION

- SIGNAL

+ SIGNAL

• It is recommended that the negative side of the power supply be grounded.

• It is possible to power up to eight 350 ohm load cells or sixteen 700 ohm load cells.

• Connect terminal “0 VDC” to the RS-485 common of the connected instruments in the event that these receive alternating current input or that they have an opto-isolated RS-485.

• In case of an RS-485 network with several devices it is recommended to activate the 120 ohm termination resistance on the two devices located at the ends of the network, see Section 2.5.1 “RS-485 Serial Communication” on page 25

2 outputs: configurable setpoints or remote output management via protocol. 2 inputs (Default: SEMI-AUTOMATIC ZERO input 1; NET/GROSS input

2): settable to have the following functions: SEMI-AUTOMATIC ZERO, NET/GROSS, PEAK, or REMOTE CONTROL (see Section 2.6 “Outputs

And Inputs Configuration” on page 26).

6 SCT Weight Transmitter Operator’s Manual

1.5 LED and Key Functions

ESC

TARE

ESC

TARE

Note

LED Main function Secondary function *

NET Net weight LED: net weight display (semi-

automatic tare or preset tare) Zero LED (deviation from zero not more than +/-

0.25 divisions)

Stability LED LED lit: output 1 closed kg Unit of measure: kg LED lit: output 2 closed g Unit of measure: g No meaning L Unit of measure:lb No meaning

* To activate the secondary LED function, during weight display press and hold

, then press .

Long press

Key Short press

(3 sec) Into menus

Zero Setting Cancel or return to previous

Escape

Captures Tare Gross  Net

Removes Tare Net  Gross

Scroll/

Backspace

mV load cell test

Next/ Data

Entry

Setting setpoints and hysteresis

Enter

LED lit: input 1 cosed

LED lit: input 2 closed

Select figure to be modified or return to previous menu item

Modify selected figure or go to next menu item

Confirm or enter in submenu

+ Setting general parameters (press and hold then press

to enter set-up menu.

+ Setting preset tare (press and hold then press to enter

set-up menu.

The LEDs light up in sequence to indicate that a setting and not a weight is being viewed.

Introduction 7

1.6 Instrument Commissioning

Note

1. Plug power cord in to outlet to turn on indicator, the display shows in sequence:

-“SU” followed by the software code (e.g.: SU S );

-- “r” followed by the software version (e.g.: r 1.04.01 );

-- “HU” followed by the hardware code (e.g.: HU 104 );

- - the serial number (e.g.:1005 15 );

2. Check that the display shows the weight and that when loading the load cells there is an increase in weight.

3. If there is not, check and verify the connections and correct positioning of the load cells.

If instrument has NOT been calibrated complete Section 2.1 before proceeding to next step.

4. Reset to zero. See Section 2.1.3 “Zero Setting” on page 15.

5. Check the calibration with test weights and correct the indicated weight if necessary. See Section 2.1.5 “Weight (Span) Calibration (With Test Weights)” on page 16.

6. If you use the analog output, set the desired analog output type and the full scale value. See Section 2.4 “Analog Output” on page 21.

7. If you use serial communication, set the related parameters. See Section

2.5 “Serial Communication Settings” on page 23.

8. If setpoints are used, set the required weight values and the relevant

parameters. See Section 2.8 “Setpoints Programming” on page 29 and Section 2.6 “Outputs And Inputs Configuration” on page 26.

1.6.1 If The Instrument Has Not Been Calibrated

Missing plant system identification tag, proceed with calibration:

1. If load cells data are unknown, follow the procedure in Section 2.1.5 “Weight (Span) Calibration (With Test Weights)” on page 16.

2. Enter the rated data of load cells following the procedure given in Section 2.1.1 “Theoretical Calibration” on page 14.

8 SCT Weight Transmitter Operator’s Manual

2.0 Configuration

CALIB FILTER PARA 0

SERIAL

0 SET

AUTO 0

TRAC 0

TESTOut-In

2 3 4 5

8 9

See

Serial

Submenu

See

Calib

Submenu

See

Serial

Submenu

OUT

NU CEL

Enter #

ANALOG

MODE

TYPE

Enter #

0-10 V

0-20 mA

4-20mA

ANA 0 ANA FS COR FSCOR 0

Enter #

Enter #Enter #

-5+5 V

-10+10 V

0-5 V

Gross

Net

000000

PtArE

SEtP1

Figure 2-1. Scale Menu Structure

Configuration 9

Parameter Choices Description

CALIb FS-tEO

See Section 2.1“Calibration” on page 11.

SEnS I b dI UI S NASS ZErO 1 NP 0 WEIGHt unIt COEFF

FILTER 0-9

4 *

PArA 0 0 SEt

AuTO 0 trAC 0

ANALOG tYPE

NOdE ANA 0 ANA FS COr 0 COr FS

SErIAL rS-485

bAud Addr dELAY PArItY STOP

Out-In Out 1

Out 2 In 1 In 2

tESt In

Out ANALOG NU-CEL

- indicates default value.

Allows a stable weight display to be obtained. See Section 2.2 “Filter On The Weight” on page 19.

See Section 2.3 “Zero Parameters” on page 20.

See Section 2.4 “Analog Output” on page 21.

See Section 2.5 “Serial Communication Settings” on page 23.

See Section 2.6 “Outputs And Inputs Configuration” on page 26.

See Section 2.7 “Test” on page 28.

Table 2-1. Scale Menu

10 SCT Weight Transmitter Operator’s Manual

2.1 Calibration

dI UI S

WEIGHt

unIt

COEFF

LItrE

bAr AtN

PI ECE

nEUton

OtHEr

HI LOG

HI LO-N

nEU-N

G t

FS-tEO

Enter #

SEnS Lb

Enter #

NASS

Enter #

ZErO

Enter #

Enter # Enter #

I NP 0

Enter #

100

0.0001

0.0002

0.002

0.005

0.001

0.0005

2 5

0.02

0.05

0.01

0.2

0.5

0.1

FILtEr

PArA 0 SErIAL

tESt

Out-In

ANA LOG

000000

SEtP1

CALIb

PtArE

Note

Figure 2-2. Calibration Menu Structure

Parameter Choices Description

FS-TED Enter #

deno *

System Full Scale is determined by multiplying one load cell capacity by the number of load cells used. Example of system full scale value calculation:

4 cells of 1000kg ---->

FULL SCALE = 1000 X 4 = 4000

The instrument is supplied with a theoretical full scale value deno

SENS LB Enter #

0.50000

7.00000

2.00000 *

Sensitivity is a load cell rated parameter expressed in mV/V. Set the average sensitivity value indicated on the load cells. I Example of 4-cell system with sensitivity

2.00100, 2.00150, 2.00200, 2.00250;

calculated as (2.00100 + 2.00150 + 2.00200 +

Table 2-2. Calibration Menu

corresponding to 10000. To restore factory values, set 0 as full scale.

enter 2.00175,

2.00250) / 4.

Configuration 11

Parameter Choices Description

TARE

dI UI S 1

2 * 5 10

Division (resolution) - the weight increment (display division size) that the scale counts by. Selections are: 0.0001 and 100 with x1 x2 x5 x10 increments.

20 50 100

0.0001

0.0002

0.0005

0.001

0.002

0.005

0.01

0.02

0.05

0.1

0.2

0.5

NASS Enter #

0 *

to max full scale

Maximum capacity (Live Load/Product) that can be displayed. When the weight exceeds this value by 9 divisions, the display will go to dashes, indicating overload. Setting this value to 0 will disable the over capacity function.

ZErO

Used to capture the deadload of the scale system. With the scale empty, the displayed value

can be zeroed off. This menu may also be accessed directly from the weighing mode to compensate for zero changes or variations.

Press to display the accumulated weight that

has been zeroed off.

INP 0 Enter #

0 to 999999 0 *

Estimated dead load value of the scale when a scale contains product that cannot be removed. The value entered is the dead load. This value will be replaced if the zero function is performed later.

Table 2-2. Calibration Menu

12 SCT Weight Transmitter Operator’s Manual

Parameter Choices Description

Note

WEIGHT Enter #

0 *

UNIT G

COEFF Enter #

- indicates default value.

t Lb * nEUton LI trE bAr AtN PI ECE nEU-N HI LO-N OtHEr HI LOG

0-99.9999 0 *

Weight (Span) Calibration - after the Theoretical Calibration has been completed and zero is set, the calibration can be adjusted with actual test weights by changing the displayed value in this parameter.

If changes are made to the theoretical Full Scale (

SEnSIb

( parameters, the weight (span) calibration is cancelled and the theoretical calibration is initiated and applied.

If the theoretical full scale ( capacity full scale ( (span) calibration ( currently in use is theoretical; if they are different, the calibration in use is the weight (span) calibration based on calibration weights.

If changes are made to the theoretical full scale (

FS-tEO

divisions ( parameters containing a weight value will be set to default values (setpoints, hysteresis, etc.).

Unit of Measure - select to determine what unit of measure is displayed and printed.

See Section 2.1.6 “Setting Units of Measure” on page 17 for description of units.

Multiplier Value entered will display an alternative unit of measure if the digital input is set for COEFF and is in a closed state.

), the capacity full scale (

dI UI S

FS-tEO

) or Divisions (

FS-tEO

NASS

) are equal in weight

WEIGHt

), then the calibration

) parameters, all the system’s

), the Sensitivity

dI UI S

)

) and the

NASS

) or

Table 2-2. Calibration Menu

To calibrate the instrument, the “Theoretical Calibration” on page 14 must be completed first. After Theoretical Calibration is set, the scale can be set with actual weights (see Section 2.1.5 “Weight (Span) Calibration (With Test Weights)” on page 16).

Configuration 13

2.1.1 Theoretical Calibration

Note

ESC

TARE

ESC

Note

ESC

This function allows load cell rated values to be set. To perform the theoretical calibration set FS-tED, SEnS lb and dI UI S in

sequence:

When entering a menu, the LED’s will begin scrolling, when selection is made and confirmed the LED’s will be off.

1. Press and hold , then press , CALIb will be displayed.

2. Press , FS-tEO is displayed. Press .

3. Press or

until total load cell capacity (system full scale) is

displayed, press .

4. Press or

5. Press or

until SEnS lb is displayed, press .

until desired load cell mV/V is displayed,

press .

6. Press or

7. Press or

until dI UI S is displayed, press .

until desired display division size is displayed,

press .

8. This complete the Theoretical Calibration, press twice to exit setup menu or continue to Section 2.1.2.

By modifying the theoretical full scale, the sensitivity or divisions, the weight (span) calibration is cancelled and the theoretical calibration only is considered valid.

If the theoretical full scale and the recalculated full scale in weight (span) calibration (see Section 2.1.5) are equal, this means that the calibration currently in use is theoretical; if they are different, the calibration in use is the weight (span) calibration based on test weights.

By modifying the theoretical full scale, the sensitivity or divisions and all the system’s parameters containing a weight value will be set to default values (setpoints, hysteresis, etc.).

2.1.2 Maximum Capacity (NASS )

Maximum capacity (live load/product) that can be displayed. When the weight

exceeds this value by 9 divisions the following is displayed ‘ overload. To disable this function, set to 0.

------

’, indicating

1. Press and hold , then press . CALIb will be displayed.

14 SCT Weight Transmitter Operator’s Manual

2. Press , FS-tEO is displayed.

TARE

ESC

Note

ESC

TARE

ESC

Note

TARE

Important

ESC

TARE

ESC

3. Press or until NASS is displayed, press . LED’s will begin scrolling.

4. Press or until desired capacity is displayed, press .

5. Press twice to exit set-up menu.

2.1.3 Zero Setting

Perform this procedure after having set the “Theoretical Calibration” on page 14.

This menu may also be accessed directly from the weight display,

press and hold for 3 seconds.

1. Press and hold , then press . CALIb will be displayed.

2. Press , FS-tEO is displayed.

3. Press or until ZErO is displayed, press .

4. The weight value to be set to zero is displayed. In this phase all of the

LEDs are flashing. Press , the weight is set to zero (the value is stored to the permanent memory).

5. Press twice to exit set-up menu.

Press to display the accumulated deadload that has been zeroed off by the instrument, displaying the sum of all of the

previous zero settings.

2.1.4 Zero Value Manual Entry

Perform this procedure only if it is not possible to reset the weighed structure tare, for example because it contains product that can not be unloaded.

Set in this parameter the estimated zero value.

1. Press and hold , then press . CALIb will be displayed.

2. Press , FS-tEO is displayed.

3. Press or until INP 0 is displayed, press . LED’s will begin scrolling.

4. Press or until desired dead load is displayed, press .

5. Press twice to exit set-up menu.

Configuration 15

2.1.5 Weight (Span) Calibration (With Test Weights)

ESC

TARE

ESC

Important

Note

After performing Section 2.1.1 “Theoretical Calibration” on page 14 and Section

2.1.3 “Zero Setting” on page 15, this function allows correct calibration to be done using test weights of known value, if necessary, any deviations of the indicated value from the correct value to be corrected.

1. Load the test weight onto the scale, use as high a percentage of the maximum quantity to be weighed as possible.

2. Press and hold , then press . CALIb will be displayed.

3. Press , FS-tEO is displayed.

4. Press or

until UEIGHt is displayed, press .

5. The value of the weight currently on the system will be flashing on the display. All of the LEDs are off. (If adjustment is not required, skip to step 8.)

6. Adjust the value on display to match weight loaded on the scale if

necessary, by pressing or . The LED’s will begin scrolling.

7. Press , the new set weight will appear with all the LEDs flashing.

8. Press again, UEIGHt will be displayed.

9. Press twice to exit set-up menu.

Example: For a system of maximum capacity of 1000 kg and 1 kg division, two test

weights are available, one 500 kg and one 300 kg. Load both weights onto the system and correct the indicated weight to 800. Now remove the 300 kg weight, the system must show 500; remove the 500 kg weight, too; the system must read zero. If this does not happen, it means that there is a mechanical problem affecting the system linearity.

Identify and correct any mechanical problems before repeating the procedure.

If theoretical full scale and recalculated full scale in weight (span) calibration are equal, it means that the theoretical calibration is currently in use; otherwise, the weight (span) calibration based on test weights is in use.

If the correction made changes the previous full scale for more than 20%, all the parameters with settable weight values are reset to default values.

Linearization Option On Max 5 Points:

It is possible to perform a linearization of the weight repeating the abovedescribed procedure up to a maximum of five points, using five different test weights.

16 SCT Weight Transmitter Operator’s Manual

The procedure ends by pressing or after entering the fifth value; at this

ESC

TARE

ESC

Note

ESC

TARE

point it will no longer be possible to change the calibration value, but only to perform a new weight (span) calibration. To perform a new calibration, should return to the weight display and then re-entering into the calibration menu.

By pressing after having confirmed the test weight that has been set, the full scale appears, recalculated according to the value of the maximum test weight

entered and making reference to the cell sensitivity set in the theoretical calibration (SEnSI b).

2.1.6 Setting Units of Measure

1. Press and hold , then press . CALIb will be displayed.

2. Press , FS-tEO is displayed.

3. Press or

until unIt is displayed, press .

4. Press or until desired unit is displayed, press .

5. Press twice to exit set-up menu.

HI LOG kilograms bAr bar* G grams AtN atmospheres* t tons PI ECE pieces* Lb pounds* nEU-N newton metres* nEUton newton* HI LO-N kikgram metres*

LI tre litres* OtHEr

other generic units of measure not included in list*

* Indicates it is possible to set the display coefficient. To use COEFF it is

necessary to enable it, closing the COEFF input. See Section 2.1.7 “Display Coefficient” on page 17.

If the print function is enabled, the symbol of the selected unit of measure will be printed after the measured value.

2.1.7 Display Coefficient

By setting the coefficient the display is changed accordingly. If one of the inputs is set to COEFF mode (see Section 2.6 “Outputs And Inputs

Configuration” on page 26) when the input is closed the value will be displayed modified according to the coefficient; when the input is opened the standard weight display will be restored.

1. Press and hold , then press . CALIb will be displayed.

2. Press , FS-tEO is displayed.

3. Press or

until COEFF is displayed, press . LED’s will

begin scrolling.

Configuration 17

4. Press or until desired number is displayed, press .

TARE

ESC

Important

5. Press twice to exit set-up menu.

HI LOG kilograms G grams t tons

nEUton

LI tre

bAr

AtN

pounds Value set in COEFF will be multiplied by the weight value

currently displayed

newton Value set in COEFF will be multiplied by the weight value

currently displayed

litres in COEFF set the specific weight in kg/l, assuming that

the system is calibrated in kg

bar Value set in COEFF will be multiplied by the weight value

currently displayed

atmospheres Value set in COEFF will be multiplied by the weight value

currently displayed

PI ECE pieces in COEFF set the weight of one piece

nEU-N

HI LO-N

OtHEr

newton metres Value set in COEFF will be multiplied by the weight value

currently displayed

kikgram metres Value set in COEFF will be multiplied by the weight value

currently displayed

other generic units of measure not

Value set in COEFF will be multiplied by the weight value currently displayed

included in list

Table 2-3. Coefficient Value by Unit of Measure

All other settings (setpoints, hysteresis, calibration ...) are expressed in weight value. If you want to convert them to the new unit of measurement, perform one of the following procedures for changing the system calibration.

The parameter must remain set to 1.0000.

Theoretical Calibration For Other Units Of Measure

Set in the parameter the F.SCALE value divided by the conversion coefficient from kg to the new unit of measure.

Example: The 4 load cells of 1000 kg are placed under a scale for oil, which has a specific gravity of 0.916 kg / l. Setting the F.SCALE = (4x1000) / 0916 = 4367, the system works in liters of oil. If you set the unit to liters, the system will display and print the symbol ‘l’ instead of ‘kg’. See Section 2.1.6 “Setting Units of Measure” on page 17.

Weight (Span) Calibration For Other Units Of Measure

Load a known quantity of product liters on the scale (equal to at least 50% of the maximum amount that you must weigh) and enter in the parameter UEI GHt, the product loaded value in liters. If you set the units to liters, the system will display and print the symbol ‘l’ instead of ‘kg’. See Section 2.1.6 “Setting Units of Measure” on page 17.

18 SCT Weight Transmitter Operator’s Manual

2.2 Filter On The Weight

ESC

TARE

ESC

Note

The filtering selection is used to eliminate environment noise, and is typically a compromise between responsiveness and stability. The lower the number, the more responsive the display will be to weight changes. The filter is used to stabilize a weight as long as the variations are smaller than the corresponding “Response Time”. The filter setting is dependent on the type of application and the required update rate.

Setting this parameter allows a stable weight display to be obtained. To increase the effect (weight more stable), increase the value.

1. Press and hold , then press . CALIb will be displayed.

2. Press or until FILtEr is displayed, press . LED’s will begin scrolling.

3. Press or until desired filter value is displayed, press

4. The weight is displayed (all LED’s will be flashing) and the displayed

stability can be experimentally verified. Press .

5. If stability is not satisfactory, press , this returns indicator to FILtEr option and the filter may be modified again until an optimum result is

achieved.

6. Press to exit set-up menu.

The filter enables to stabilize a weight as long as its variations are smaller than the corresponding “Response Time”. It is necessary to set this filter according to the type of application and to the full scale value set.

Filter Value

Response times

[ms]

Display and serial port refresh frequency

[Hz]

080 80 1190 80 2260 40 3450 26

4* 900 13

5 1700 13 6 2500 13 7 4200 10 8 6000 10 9 7500 5

* indicates default value.

Table 2-4. Filter Settings

Configuration 19

2.3 Zero Parameters

ESC

TARE

ESC

1. Press and hold , then press . CALIb will be displayed.

2. Press or until PArA 0 is displayed, press .

3. Press or until desired parameter (see Table 5 ) is displayed,

press . The currently programmed value is displayed and LED’s

will be scrolling.

4. Press or until desired value is displayed, press .

5. Press twice to exit set-up menu.

Parameter Choices Description

0 SEt Enter #

0-max full scale

300 *

Considered decimals: 300 – 30.0 – 3.00 – 0.300

AutO 0 Enter #

0 - max 20% of full scale

0 *

trAC 0 nOnE *

1-5

- indicates default value.

Table 2-5. Zero Parameters Settings

Resettable Weight setting for small weight change.

Indicates the maximum weight value resettable by external contact, keypad or serial protocol

Automatic zero setting at power-on

If when indicator is powered on the weight value is lower than the value set in this parameter and does not exceed the 0 SEt value, the weight is reset. To disable this function set to 0.

Zero tracking

When the zero weight value is stable and, after a second, it deviates from zero by a figure in divisions smaller or equal to the figure in divisions set in this parameter, the weight is set to zero. To disable this function, set to none

Example: if the parameter dI UI set to 5 and trAC 0 is set to 2, the weight will be automatically set to zero for variations smaller than or equal to 10 (dI UI S x trAC 0 ).

20 SCT Weight Transmitter Operator’s Manual

2.4 Analog Output

Note

Parameter Choices Description

tYPE 4-20 mA *

0-20 mA 0-10 V 0-5 V

-10 +10 V

-5 +5 V

NodE Enter #

Gross Net

ANA 0 Enter # Set the weight value for the minimum analog output

ANA FS Enter # Set the weight value for the maximum analog output

COr 0 Analog output correction to zero: if necessary adjust

COr FS Full scale analog output correction: if necessary

- indicates default value.

Selects the analog output type.

See “Soldered Jumper” on page 22 See “Soldered Jumper” on page 22

Select mode to be tracked, gross or net. If the net function is not active, the analog output varies according to gross weight.

value.

Only set a value different from zero to limit the analog output range.

E.G.:: for a full scale value of 10000 kg, a 4 mA signal at 5000 kg is required, and 20 mA at 10000 kg, in this case, instead of zero, set 5000 kg.

value; it must correspond to the value set in the PLC program (default: calibration full scale).

E.g.: if using a 4-20 mA output and in the PLC program a 20 mA = 8000 kg is desired, set the parameter to 8000.

the analog output, allowing the PLC to indicate 0. The sign ‘-‘ can be set for the last digit on the left.

E.g.: For a 4-20 mA output and a minimum analog setting, the PLC or tester reads 4.1 mA. Set the parameter to 3.9 to obtain 4.0 on the PLC or tester. (See “Analog Output Type Scale Corrections” on page 22)

adjust the analog output, allowing the PLC to indicate the value set in the AnA FS parameter.

E.g. For a 4-20 mA output with the analog set to full scale and the PLC or tester reads 19.9 mA, set the parameter to 20.1 to obtain 20.0 on the PLC or tester. (See “Analog Output Type Scale Corrections” on page 22)

Table 2-6. Analog Output Menu

Configuration 21

Soldered Jumper

Note

For the output -10 +10 V and -5 +5 V the soldered jumper J7 must be closed:

• Remove the face plate of the instrument by removing the screws that attach it to the little columns on the printed circuit board.

• On the circuit board, locate the jumper J7, situated above the 3 and 4 terminals at about mid board.

• Scrape away the solder from the jumper bay, until the copper underneath is uncovered.

• Close the jumper short circuiting the bays, it is also recommended that a small piece of copper wire without insulation or a leg wire be used to facilitate the operation.

Analog Output Type Scale Corrections

Minimum and maximum values which can be set for the zero and full scale corrections

Analog Output Type Minimum Maximum

0–10 V -0.150 10.200

0–5 V -0.150 5.500

-10 +10 V -10.300 10.200

-5 +5 V -5.500 5.500 0-20 mA -0.200 22.000 4-20 mA -0.200 22.000

The analog output may also be used in the opposite manner, i.e. the weight setting that corresponds to the analog zero may be greater than the weight set for the analog full scale. The analog output will increase towards full scale as the weight decreases; the analog output will decrease as the weight increases.

E.g.: analog output type having selected 0-10V ANA 0 = 10000 ANA FS = 0 Weight = 0 kg analog output = 10 V Weight = 5000 kg analog output = 5 V Weight = 10000 kg analog output = 0 V

22 SCT Weight Transmitter Operator’s Manual

2.5 Serial Communication Settings

Addr

bAud

HErt2

dELAY

PArItY

StOPrS485

nOnE

NodbUS

ASCII

Cont In

rI P

HdrI P

HdrI Pn

Enter #

9600 19200 38400

115200

4800

2400

30 40 50 60

Enter #

EUEn

Odd

nOnE

2 3 4 5

8 9

CALIb

FILtEr

PArA 0

SErIAL

tESt

Out-In

ANA LOG

Figure 2-3. Serial Communications Menu Structure

According to the chosen protocol only the necessary settings will be displayed in sequence.

Parameter Choices Description

rS-485

(Communitcation Port)

None * Disables any type of communication (default). NOdbuS MODBUS-RTU protocol; possible addresses: from

1 to 99 (see Section 3.6)

ASCII ASCII bidirectional protocol; possible addresses:

from 1 to 99 (see Section 3.7)

NOdU6-

NOd td

COntIn Continuous weight transmission protocol (see

Section 3.8), at the frequency set in HERTZ parameter (from 10 to 300). NOd t(set: PARITY=none, STOP=1)

NOd td(set: PARITY=none, STOP=1)

rI P Continuous weight transmission protocol, streams

net and gross (see Section 3.9) (set: BAUD=9600,PARITY=none, STOP=1)

Hdr1 P Continuous weight transmission protocol, streams

net and gross including decimal (see Section 3.9) (set: BAUD=9600,PARITY=none, STOP=1)

Table 2-7. Serial Communications Menu

Configuration 23

Parameter Choices Description

rS-485 (cont) Hdr1 PN Continuous weight transmission protocol (see

Section 3.9)

When the remote display is set to gross weight:

- if the instrument displays the gross weight, the remote display shows the gross weight.

- if the instrument shows the net weight the remote display shows the net weight alternated with the message “net”

bAud 2400

4800 9600 * 19200 38400 115200

Addr 1-99

1 *

HErTZ Maximum Transmission Frequency - to be set

10Hz * 20Hz Max setting with min 2400 baud rate 30Hz 40Hz Max setting with min 4800 baud rate 50Hz 60Hz 70Hz 80Hz Max setting with min 9600 baud rate

dELAY 0-200

msec

0 *

PArItY nOnE *

EVEn odd

StOP 1 *

- indicates default value.

Transmission speed.

Instruments address

when the CONTIN transmission protocol is selected. (see Table 2-4 on page 19)

Delay in milliseconds which elapses before the instrument replies

parity none even parity odd parity

Stop bit

Table 2-7. Serial Communications Menu

24 SCT Weight Transmitter Operator’s Manual

2.5.1 RS-485 Serial Communication

SCTSCT

SCT

RS485 +

RS485 -

max 500 m

RS485 +

RS485 -

PC RS232

RX+

RX-

TX-

TX+

Converter

24 Vcc

VIN

RS485 +

RS485 -

RS485 termination

0 VDC

RS485 +

RS485 -

0 VDC

RS485 +

RS485 -

0 VDC

5 2 3

28 29

28 29 34

28 29

J2 J1

Figure 2-4. RS-485 Serial Communications

Configuration 25

If the RS-485 network exceeds 100 metres in length or baud-rate

Note

OUt 1

OUt 2 In 1 IN 2

OPEn

SEt 1

PLC

GrOSS

NEt

2ErO PEAH

COntI n

PLC

nE-lO

COEFF

2Er0 PEAH

COntI n

PLC

nE-lO

COEFF

OPEn

SEt 2

StAbLE

POS/nEG

POS nEG

OFF

CALIb

FILtEr

PArA 0 SErIAL

tESt

Out-In

ANA LOG

StAbLE

PLC

over 9600 are used, close the two jumpers, called "RS-485 termination", to activate two 120 ohm terminating resistors between the ‘+’ and ‘–’ terminals of the line, on the terminal strip of the furthest instrument. Should there be different instruments or converters, refer to the specific manuals to determine whether it is necessary to connect the above-mentioned resistors.

Direct Connection Between RS-485 And RS-232 Without Converter

Since a two-wire RS-485 output may be used directly on the RS-232 input of a PC or remote display, it is possible to implement instrument connection to an RS232 port in the following manner:

Instrument RS-232

RS-485 - RXD RS-485 + GND

This type of connection allows a SINGLE instrument to be used in a ONE WAY mode.

2.6 Outputs And Inputs Configuration

Figure 2-5. Outputs and Inputs Menu Structure

26 SCT Weight Transmitter Operator’s Manual

Parameter Choices Description

OUt 1 OUt 2

SEt 1 SEt 2

OPEn Normally Open: the relay is de-energized and the

contact is open when the weight is lower than the programmed setpoint value; it closes when the weight is higher than or equal to the programmed setpoint value.

CLOSE * Normally closed: the relay is energized and the

contact is closed when the weight is lower than the programmed setpoint value; it opens when the weight is higher than or equal to the programmed setpoint value.

SEt 1 SEt 2

PLC The contact will not switch on the basis of weight, but is

StAbLE Relay switching occurs when the weight is stable. POSnEG * Relay switching occurs for both positive and negative

POS Relay switching occurs for positive weight values only. NEG Relay switching occurs for negative weight values only. OFF * Relay switching will not occur if the setpoint value is ‘0’. On Setpoint = ’0’ and nodbus=posneg, relay switching

Number corresponds with OUT 1or 2. The contact will switch on the basis of weight, according to setpoints (see Section 2.8 “Setpoints Programming” on page 29) Select:

Gross (default) - the contact will switch on the basis of gross weight.

Net - the contact will switch on the basis of net weight (If the net function is not active, the contact will switch on the basis of gross weight).

controlled by remote protocol commands.

weight values.

occurs when the weight is ‘0’; the relay will switch again when the weight is different from zero, taking hysteresis into account (both for positive and for negative weights).

Setpoint = ’0’ and nodes=pos, relay switching occurs

for a weight higher than or equal to ‘0’, the relay will switch again for values below ‘0’, taking hysteresis into account.

Setpoint = ’0’ and nodes=neg, relay switching occurs

for a weight lower than or equal to ‘0’, the relay will switch again for values above ‘0’, taking hysteresis into account.

Table 2-8. Output and Input Menu

Configuration 27

Parameter Choices Description

ESC

TARE

ESC

In 1 In 2

- indicates default value.

nE-LO *

(In 2 default)

(NET/GROSS): by closing this input for less than one second, it performs a SEMI-AUTOMATIC TARE and the display will show the net weight. To display the gross weight again, hold the NET/GROSS input closed for 3 seconds.

2ErO *

(In 1 default)

By closing the input for less than one second, the weight is set to zero (see Section 3.3 “Semi-Automatic Zero (Weight Zero-setting For Small Variations)” on page 33).

PEAH With the input closed the maximum weight value

reached remains on display. Opening the input the current weight is displayed.

PLC Closing the input no operation is performed, the input

status may however be read remotely by way of the communication protocol.

COntin Closing the input for less than one second the weight is

transmitted via the serial connection according to the fast continuous transmission protocol one time only (only if contin is set in the item serial).

COEFF When the input is closed the weight is displayed based

on the set coefficient (see Section 2.1.6 “Setting Units of Measure” on page 30 and Section 2.1.7 “Display Coefficient” on page 31), otherwise the weight is displayed.

Table 2-8. Output and Input Menu

2.7 Test

1. Press and hold , then press . CALIb will be displayed.

2. Press or until tEst is displayed, press . The currently

programmed value is displayed.

3. Press or until desired parameter is displayed, press .

4. For In and NU-CEL, current reading is displayed, press .

For Out, press until corresponding value of the out you want to

change is flashing, press to change the value, press .

5. Press twice to exit set-up menu.

28 SCT Weight Transmitter Operator’s Manual

Parameter Choices Description

TARE

ESC

Note

In N/A Input Test - for each open input 0 is displayed, 1 is

displayed when the input is closed.

Out 0 *

Output Test Setting 0 - the corresponding output opens. Setting 1 - the corresponding output closes.

ANALOG ANALOG Allows the analog signal to range between the minimum

and the maximum values starting from the minimum.

NA current output test UOLt1 voltage output test

NU-CEL N/A Millivolt Test - displays the load cell response signal in

mV with four decimals.

- indicates default value.

Table 2-9. Test Menu

2.8 Setpoints Programming

1. Press to enter setpoints and hysteresis settings.

2. Press or

until desired setpoint or hysteresis parameter is

displayed, press .

3. Press or until desired value is displayed, press .

4. Press to exit setpoints and hysteresis settings.

These values are set to zero if the calibration is changed significantly (see Section 2.1.1 “Theoretical Calibration” on page 14 and Section 2.1.5 “Weight (Span) Calibration (With Test Weights)” on page 16).

Parameter Choices Description

SEtP 1 SEtP 2

HYStE 1 HYStE 2

- indicates default value.

0-Full Scale

0 *

0-Full Scale

0 *

Setpoint; relay switching occurs when the weight exceed the value set in this parameter. The type of switching is settable (see “Outputs And Inputs Configuration” on page 26).

Hysteresis, value to be subtracted from the setpoint to obtain contact switching for decreasing weight. For example with a setpoint at 100 and hysteresis at 10, the switching occurs at 90 for decreasing weight.

Table 2-10. Setpoints

Configuration 29

2.9 Reserved For The Installer

Important

ESC

Note

ESC

TARE

ESC

Note

2.9.1 Default Scale

Operation must only be performed after contacting technical assistance

1.With power off, press and hold , then power on.

Display shows PrOG .

2. Press , display shows bASE.

3. Press , display shows UAIt.

4. Instrument will reboot.

By confirming the displayed program, the system variables are set with default values.

2.9.2 Program Selection - Reverse:

Scale capacity is displayed when scale is empty. As weight is added display will count down.

1. With power off, press and hold , then power on.

Display shows PrOG .

2. Press , display shows bASE.

3. Press , display shows rEuEr.

4. Press , display shows UAIt.

5. Instrument will reboot.

By pressing you will quit the program without introducing any changes and without deleting any of the set variables.

If you do not have a specific manual for the newly set program, you can request it from technical assistance.

30 SCT Weight Transmitter Operator’s Manual

2.9.3 Keypad Or Display Locking

ESC

TARE

1. Press immediately followed by , hold them down for about 5 seconds (this operation is also possible via the MODBUS and ASCII

protocols):

2. Press or until desired parameter is displayed, press .

Parameter Description

FrEE no lock KEY keypad lock: if active, when key is pressed the message bLOC is

displayed.

dI SP Keypad and Display lock: if active, the keypad is locked and the

display shows the instrument model (weight is not displayed); by pressing a key the display shows bLOC for 3 seconds.

Configuration 31

3.0 Operation

Note

TARE

Note

TARE

ESC

Note

TARE

3.1 Semi-Automatic Tare (Net/Gross)

The semi-automatic tare value is lost upon instrument power-off.

The semi-automatic tare operation is not allowed if the gross weight is zero.

1. To capture tare and weigh in net mode (SEMI-AUTOMATIC TARE),

close the NET/GROSS input or press for 3 seconds. The

instrument displays the net weight (zero) and the NET LED lights up.

2. To display the gross weight again, keep the NET/GROSS input closed

or press for 3 seconds.

3. This operation can be repeated by the operator to allow the loading of several products.

Press and hold to display the gross weight temporarily. When

is released, the net weight will be displayed again.

3.2 Preset Tare (Subtractive Tare Device)

It is possible to manually set a preset tare value to be subtracted from the display value provided that the P-tArE ≤ max capacity.

1. Press and hold and to display P-tArE, press .

2. Press or until desired value is displayed, press .

3. Press to exit P-tArE.

4. After setting the tare value, go back to the weight display, the display shows the net weight (subtracting the preset tare value) and the NET LED lights up to show that a tare has been entered.

Press and hold for 3 seconds to display the gross weight

temporarily. When is released, the net weight will be displayed again.

To delete a preset tare and return to the gross weight display:

1. Press hold for 3 seconds or keep the NET/GROSS input (if any) closed for the same length of time (3 seconds). The preset tare value is

set to zero. The NET LED is turned off when the gross weight is displayed once again.

32 SCT Weight Transmitter Operator’s Manual

If a semi-automatic tare (net) is entered, it is not possible to access

Note

ESC

the enter preset tare function. If a preset tare is entered, it is still possible to access the

semiautomatic tare (net) function. The two different types of tare are added.

All the semi-automatic tare (net) and preset tare functions will be lost when the instrument is turned off.

3.3 Semi-Automatic Zero (Weight Zero-setting For Small Variations)

By closing the SEMI-AUTOMATIC ZERO input, the weight is set to zero. The zero setting will be lost when the instrument is turned off.

This function is only allowed if the weight is lower than the 0 set value (see 0 SET in Section 2.3 “Zero Parameters” on page 20), otherwise the t

-----

alarm

appears and the weight is not set to zero.

3.4 Peak

By keeping the input closed the maximum weight value reached remains displayed. Opening the input the current weight is displayed.

If you wish to use this input to view a sudden variation peak, set the FILTER ON THE WEIGHT (see Section 2.2) to 0.

3.5 Alarms

Display Description

ErCEL Load cell is not connected or is incorrectly connected; the load cell signal

Er OL Weight display exceeds 110% of the full scale. Er Ad Internal instrument converter failure; check load cell connections, if

---------

Er OF Maximum displayable value exceeded (value higher than 999999 or lower

-------

t NAH-PU This message appears in the test weight setting, in weight (span)

Err0r The value set for the parameter is beyond the permitted values; press

bLOC Lock active on menu item, keypad or display. nOdl SP It’s not possible to display properly the number because is greater than

exceeds 39 mV; the conversion electronics (A/D converter) is malfunctioning.

necessary contact Technical Assistance. Weight exceeds the maximum weight by 9 divisions.

than -999999). Weight too high: zero setting not possible.

calibration, after the fifth test weight value has been entered.

to quit the setting mode leaving the previous value unchanged.

Examples:

-a number of decimals is selected for full scale which exceeds the instrument's display potential;

-value above the maximum setting value;

-the weight value set in test weight verification does not match the detected mV increase.

999999 or less than -999999.

Table 3-1. Alarm Descriptions

Operation 33

-----

Note

The response to the zero command is a 'value not valid' error (error code 3)

MODE

Bit LSB

Status

MODBU

S RTU

ASCII

RIP *

HDRIP-N

CONTIN

ErCEL Er OL Er Ad --------- Er OF t

76543210 xxxxxxx1

__O-F_ __O-L_ __O-F_ __O-L_ __O-F_ &aa#CR

__O-F_ __O-L_ __O-F_ __O-L_ __O-F_ __O-F_

_ERCEL _ER_OL _ER_AD ###### _ER_OF O__SET

_ERCEL _ER_OL _ER_AD ^^^^^^ _ER_OF O__SET

76543210 xxxx1xxx

76543210 xxxxxx1x

76543210 xxxxx1xx

76543210 On gross: xxx1xxxx On net: xx1xxxxx

Table 3-2. Serial Protocols Alarms

* For RIP remote displays, if the message exceeds 5 digits the display

------

reads

Range 0/20mA 4/20 mA 0/5 V 0/10 V -10/10 V -5/5 V

Output

Value

If an alarm becomes active the relays open and the analog outputs go to the lowest possible value according to the following table:

-0.2 mA 3.5 mA -0.5 V -0.5 V 0 V 0 V

3.6 Modbus-RTU Protocol

The MODBUS-RTU protocol enables to manage the reading and writing of the registers listed here below according to the specifications contained in the reference document for this standard Modicon PI-MBUS-300.

To select the communication with MODBUS-RTU, refer to Section 2.4 “Analog Output” on page 21.

When specifically indicated certain data will be written directly to EEPROM type memories. This memory has a limited number of writing operations (100.000), therefore unnecessary operations at said locations must be avoided. The instrument, in any case, ensures that no writing occurs if the value to be stored is equal to the stored value.

The numerical data listed below are expressed in decimal notation, or hexadecimal notation if preceded by 0x.

Modbus-RTU Data Format

The data received and transmitted via MODBUS-RTU protocol have the following characteristics:

- 1 start bit

- 8 data bits, least significant bit sent first

- Instrument settable parity bit

- Instrument settable stop bit

34 SCT Weight Transmitter Operator’s Manual

Modbus Supported Functions

Among the commands available in the MODBUS-RTU protocol, only the following are used to manage communication with the instruments. Other commands may not be interpreted correctly and could generate errors or system shut-downs:

FUNCTIONS DESCRIPTION

03 (0x03) Read Holding Register (Programmable Register Reading) 16 (0x10) Preset Multiple Registers (Write Multiple DI Register)

The interrogation frequency is linked with the preset communication rate (the instrument will stand by for at least 3 bytes before beginning to calculate a possible response to the query). The dELAY parameter (see Section 2.4 “Analog Output” on page 21) allows for a further delay in the instrument response, and this directly influences the number of possible queries in the unit of time.

For additional information on this protocol, refer to the general technical specification PI_MBUS_300. The functions supported relative to the MODBUS standard are the READ HOLDING REGISTER and the PRESET MULTIPLE REGISTERS.

In general, the query and response to and from a slave instrument are organized as follows:

Function 3: Read Holding Registers (Programmable Register Reading)

QUERY

Address Function Add. Reg. 1 No. register 2 bytes

A 0x03 0x0000 0x0002 CRC

Tot. bytes = 8

RESPONSE

Address Function No. bytes Register1 Register 2 2 bytes

A 0x03 0x04 0x0064 0x00C8 CRC

Tot. bytes = 3+2*No. registers+2

Function 16: Preset Multiple Registers (Multiple Register Writing)

QUERY

Address Function

A 0x10 0x0000 0x0002 0x04 0x0000 0x0000 CRC

Add.

reg. 1 No. reg.

No.

bytes

Val .

reg.1

Val .

reg.2 2 bytes

Tot. bytes = 7+2*No. registers+2

RESPONSE

Address Function Add. Reg. 1 No. register 2 bytes

A 0x10 0x0000 0x0002 CRC

Tot. bytes = 8

No. REGS: Number of registers to write beginning from the address.

Operation 35

N° BYTES: Number of bytes transmitted as a value of the registers (2

bytes per register)

VAL. REG.: Contents of the register beginning from the first.

The answer contains the register identification modified after the command has been executed.

Communication Error Management

The communication strings are controlled by CRC (Cyclical Redundancy Check).

In case of a communication error the slave will not respond with any string. The master must allow for a time-out before response reception. If no response is received it infers that a communication error has occurred.

In the event of a string received correctly but not executable, the slave responds with an EXCEPTIONAL RESPONSE. The "FUNCTION" field is transmitted

with the MSB at 1.

EXCEPTIONAL RESPONSE

Address Function Code 2 bytes

A Funct + 80h CRC

CODE DESCRIPTION

1 ILLEGAL FUNCTION (Function not valid or not supported) 2 ILLEGAL DATA ADDRESS (The specified data address is not available) 3 ILLEGAL DATA VALUE (The data received have no valid value)

List Of Usable Registers

The MODBUS-RTU protocol implemented on this instrument can manage a maximum of 32 registers read and written in a single query or response.

R = the register can be read only W = the register can be written only R/W = the register can be both read and written H = high half of the DOUBLE WORD forming the number L = low half of the DOUBLE WORD forming the number

36 SCT Weight Transmitter Operator’s Manual

Important

40001 Firmware version - R 40002 Type of instrument - R 40003 Year of Production - R 40004 Serial Number - R 40005 Active program - R 40006 Command Register NO W 40007 Status Register - R 40008 Gross Weight H - R 40009 Gross Weight L - R 40010 Net Weight H - R 40011 Net Weight L - R 40012 Peak Weight H - R 40013 Peak Weight L - R 40014 Divisions and Units of measure - R 40015 Coefficient H R 40016 Coefficient L R 40017 SETPOINT 1 H 40018 SETPOINT 1 L R/W 40019 SETPOINT 2 H R/W 40020 SETPOINT 2 L R/W 40021 HYSTERESIS 1 H R/W 40022 HYSTERESIS 1 L R/W 40023 HYSTERESIS 2 H 40024 HYSTERESIS 2 L 40025 INPUTS - R 40026 OUTPUTS NO R/W 40037 Test weight for calibration H Use with command 40038 Test weight for calibration L R/W

40043 Weight value corresponding to

ZERO of the analog output H

40044 Weight value corresponding to

ZERO of the analog output L

40045 Weight value corresponding to

Full Scale of the analog output H

40046 Weight value corresponding to

Full Scale of the analog output L

DESCRIPTION

At the time of writing, the setpoints, hysteresis values are saved to the RAM and will be lost upon the next power-off; to store them permanently to the EEPROM so that they are maintained at power-on, the ‘99’ command of the Command Register must be sent.

Saving to EEPROM ACCESS

Only after command

‘99’ of the COMMAND

‘101’ of the

COMMAND REGISTER

Only after command

‘99’ of the

Command Register.

R/W

Operation 37

Weight (Span) Calibration Commands (With Test Weights)

The instrument calibration can be changed via MODBUS. To carry out this procedure, the system must be unloaded and the weight value display reset to zero with the command ‘100’ of the Command Register. Then, a load must be placed on the system and the correct weight value must be sent to the registers 40037-40038; to save this value, send the control ‘101’ from the Command Register. If the operation is successfully completed, the two test weight registers are set to zero.

Analog Output Setting

Write the weight in the registers “Weight value corresponding to the Full Scale of analog output H” (40045) and “Weight value corresponding to the Full Scale of analog output L” (40046) or write the weight in the registers “weight value corresponding to the ZERO of the analog output H” (40043) and “weight value corresponding to the ZERO of the analog output L” (40044). After writing the value, send the command 99 from the Command Register to save it to EEPROM

memory.

Status Register

Bit 0

Bit 1

Bit 2

Bit 3

Bit 4

Bit 5

Bit 6

Bit 7

Bit 8

Bit 9

Bit 10

Bit 11

Bit 12

Bit 13

Bit 14

Bit 15

Cell Error

AD Convertor Malfunction

Maximum weight exceeded by 9 divisions

Gross weight higher than 110% of full scale

Gross weight beyond 999999 or less than -999999

Net weight beyond 999999 or less than -999999

Gross weight negative sign

Net weight negative sign

Peak weight negative sign

Net display mode

Weight stability

Weight within +/-¼ of a division around ZERO

38 SCT Weight Transmitter Operator’s Manual

Inputs Register (40025)

Note

(Read Only)

Bit 0 INPUT 1 Status Bit 0 OUTPUT 1 Status Bit 1 INPUT 2 Status Bit 1 OUTPUT 2 Status Bit 2 Bit 2 Bit 3 Bit 3 Bit 4 Bit 4 Bit 5 Bit 5 Bit 6 Bit 6 Bit 7 Bit 7 Bit 8 Bit 8 Bit 9 Bit 9 Bit 10 Bit 10 Bit 11 Bit 11 Bit 12 Bit 12 Bit 13 Bit 13 Bit 14 Bit 14 Bit 15 Bit 15

The output status can be read at any time but can be set (written) only if the output has been set as or (see Section 2.6 “Outputs And Inputs Configuration” on page 26); otherwise, the outputs will be managed according to the current weight status with respect to the relevant setpoints.

Divisions And Units Measure Registry (40014)

Outputs Register (40026)

(Read And Write)

This register contains the current setting of the divisions (parameter dI UI S ) and of the units of measure (UnI t parameter).

H Byte L Byte

Units of measure division

Use this register together with the Coefficient registers to calculate the value displayed by the instrument.

Operation 39

Least significant byte

(L Byte)

Division

value

0 100 0 0 Kilograms Does not intervene 1 50 0 1 Grams Does not intervene 2 20 0 2 Tons Does not intervene 3 10 0 3 Pounds Does not intervene 4 5 0 4 Newton Multiples 520 5 Litres Divides 6 1 0 6 Bar Multiples 7 0.5 1 7 Atmspheres Multiples 8 0.2 1 8 Pieces Divides

90.11 9 Newton

10 0.05 2 10 Kilogram

11 0.02 2 11 Other Multiples 12 0.01 2 13 0.005 3 14 0.002 3 15 0.001 3 16 0.0005 4 17 0.0002 4 18 0.0001 4

Divisor Decimals

Units of

measure

value

Most significant byte

(H Byte)

Utilization of the

Coefficient value

Units of

measure

description

Meter

with the different units of measure

settings compared

to the gross weight

Multiples

detected

40 SCT Weight Transmitter Operator’s Manual

Possible Command To Send To The Command Register (40006)

No command

NET display

SEMI-AUTOMATIC ZERO

GROSS display

Reserved

100

101

9999

Reserved

Keypad lock

Keypad and display unlock

Keypad and display lock

Save data in EEPROM

Zero-setting for calibration

Test weight storage for calibration

Reset (reserved)

3.7 ASCII Bidirectional Protocol

The instrument replies to the requests sent from a PC/PLC. It is possible to set a delay time for the instrument before it transmits a response

(see dELAY parameter in Section 2.4 “Analog Output” on page 21). The following communication modes available (see Section 2.4 “Analog Output”

on page 21):

• NOdU60:

• NOd td:

Data Identifiers:

$: Beginning of a request string (36 ASCII); & o &&: Beginning of a response string (38 ASCII); aa: 2 characters for instrument address (48 ÷ 57 ASCII); !: 1 character to indicate the correct reception(33 ASCII); ?: 1 character to indicate a reception error (63 ASCII); #: 1 character to indicate an error in the command execution (23 ASCII); ckck: 2 ASCII characters for Check-Sum (for furthers information, see

“Check-Sum Calculation” on page 45);

CR: 1 character for string end (13 ASCII); \: 1 character for separation (92 ASCII).

Operation 41

Setpoint Values Setting:

Note

The PC transmits: $aaxxxxxxyckckCR

in which:

xxxxxx = 6 characters for the setpoint value (48 ÷ 57 ASCII); y = A (set the value in the Setpoint 1) y = B (set the value in the Setpoint 2)

Possible instrument responses:

- correct reception: &&aa!

- incorrect reception: &&aa?

Setpoints Storage Into EEPROM Memory:

\ckckCR

The setpoints value relevant to the two setpoints programmed via the PC are stored to the RAM volatile memory and lost upon instrument power off. It is necessary to send a special command to save them permanently in the EEPROM memory. Please note that the number of writes allowed in the EEPROM memory is limited (about 100000).

The PC transmits: $aaMEM

ckckCR

Possible instrument responses:

- correct reception: &&aa!

- incorrect reception: &&aa?

Reading Weight, The Setpoint And The Peak (If Present) From The Pc:

\ckckCR

The PC transmits: $aajckckCR

in which:

j = a to read setpoint 1 j = b to read setpoint 2 j = t to read gross weight j = n to read net weight j = p to read the gross weight peak if the ASCII parameter is set as

NOdU60; if, instead the ASCII parameter is set on NOd td the

gross weight will be read. To read the points, set the FStE0

equal to 50000.

Possible instrument responses:

- correct reception: &aaxxxxxxj\ckckCR

- incorrect reception: &&aa?\ckckCR

- if the peak is not configured: &aa#

in which:

xxxxxx = 6 value characters of the required weight.

In case of negative weight, the first character on the left acquires the value « - » (minus sign - ASCII 45).

In case of weight value is under -99999, the minus sign (‘-‘) is sent alternated with the most significant figure.

42 SCT Weight Transmitter Operator’s Manual

Error messages:

Important

In case of an instrument alarm for exceeding 110% of the full scale or 9 divisions above the value of the parameter NASS, the instrument sends the string:

&aassO-Lst

\ckck

In case of faulty connection of the load cells or of another alarm, the instrument sends:

&aassO-Fst

\ckck

in which:

s = 1 separator character (32 ASCII – space-).

Refer to Section 3.5 “Alarms” on page 33.

Semi-Automatic Zero (Weight Zero-Setting For Small Variations)

The zero-setting will not be maintained after an instrument power-off.

The PC transmits: $aaZEROckckCR

Possible instrument responses:

- correct reception: &&aa!

- incorrect reception: &&aa?

- the current weight is over the maximum value resettable: &aa#

Switching From Gross Weight To Net Weight

\ckckCR

The PC transmits: $aaNETckckCR

Possible instrument responses:

- correct reception: &&aa!\

- incorrect reception: &&aa?

Switching From Net Weight To Gross Weight

ckckCR

\ckckCR

The PC transmits: $aaGROSSckckCR

Possible instrument responses:

- correct reception: &&aa!

- incorrect reception: &&aa?

Reading Of Decimals And Number Of Divisions

\ckckCR

The PC transmits: $aaDckckCR

Possible instrument responses:

- correct reception: &aaxy

- incorrect reception: &&aa?

\ckckCR

in which:

x = number of decimals y = division value

The y field acquires the following values:

'3' for division value = 1 '4' for division value = 2 '5' for division value = 5 '6' for division value = 10 '7' for division value = 20

Operation 43

'8' for division value = 50

Important

'9' for division value = 100

Zero Setting

(See Section 2.1.3) The PC transmit the following ASCII string containing the zeroing command:

$aaz

ckckCR

in which:

z = weight zeroing command (122 ASCII)

Possible instrument responses:

- correct reception: &aaxxxxxxt

- incorrect reception: &&aa?

\ckckCR

- If the instrument is not in gross weight displaying condition, the

response is: &aa#

in which:

xxxxxx = 6 characters for the required weight value; t = weight identification code (116 ASCII).

Example: Weight zero setting for instrument with address 2:

For the calibration, make sure that the scale is empty and the instrument measures a corresponding mV signal.

query: $02z78(Cr) response: &02000000t\76(Cr)

In case of correct weight zero setting the read value (response) must be 0 (in the string “000000”).

The zero values are stored to the EEPROM memory, please note that the number of writes allowed is limited (about

100000). If it is necessary to reset the weight quite often, it is recommended to perform it by PC or PLC program, keeping in mind the weight deviation respect to the zero instrument.

Weight (Span) Calibration (With Test Weights)

(See Section 2.1.5) After having performed the ZERO SETTING (see Section 2.1.3 “Zero Setting”

on page 15), this function allows correct calibration to be done using test weights of known value and, if necessary, any deviations of the indicated value from the correct value to be corrected.

Load onto the weighing system a test weight, Load the test weight onto the scale, use as high a percentage of the maximum quantity to be weighed as possible. Otherwise make sure that the instrument measures a corresponding mV signal.

The PC sends the following ASCII string containing the calibration command:

$aasxxxxxx

ckckCR

in which:

s = calibration command (115 ASCII) xxxxxx = 6 characters for test weight value.

Possible instrument responses:

- correct reception: &aaxxxxxxt

- incorrect reception or full scale equal to zero: &&aa?

\ckckCR

44 SCT Weight Transmitter Operator’s Manual

in which:

t = gross weight identification code (116 ASCII). xxxxxx = 6 characters to indicate the current weight value.

In case of correct calibration, the read value must be equal to test weight.

Example: Calibration for instrument with address 1 and test weight of 20000 kg:

query: $01s02000070(Cr) response: &01020000t\77(Cr)

In case of correct calibration the read value has to be “020000”.

Keypad Lock (Access Protection To The Instrument)

The PC transmits: $aaKEYckckCR

Possible instrument responses:

- correct reception: &&aa!

- incorrect reception: &&aa?

Keypad Unlock

\ckckCR

The PC transmits: $aaFREckckCR

Possible instrument responses:

- correct reception: &&aa!

- incorrect reception: &&aa?

Display And Keypad Lock

\ckckCR

The PC transmits: $aaKDISckckCR

Possible instrument responses:

- correct reception: &&aa!

- incorrect reception: &&aa?

Check-Sum Calculation

\ckckCR

The two ASCII control characters (ckck) are the representation of a hexadecimal

digit in ASCII characters. The check digit is calculated by performing the operation XOR (exclusive or) 8-bit ASCII codes of the only part of the underlined string.

The procedure to calculate the check- sum is the following:

• Consider only the string characters highlighted with underlining;

• Calculate the EXCLUSIVE OR (XOR) of the ASCII codes for the characters;

Example:

Character

0 48 30 00110000 1 49 31 00110001

t 116 74 01110100

XOR = 117 75 01110101

Decimal ASCII

Code

Hexadecimal ASCII

Code

Binary ASCII

Code

• The result of the XOR operation expressed in hexadecimal notation is made up of 2 hexadecimal digits (numbers from 0 to 9 or letters from A to F). In this case the hexadecimal code is 0x75.

• The check-sum inserted in the strings transmitted is made up of the 2 characters which represent the result of the XOR operation in hexadecimal notation (in our example the character " 7 " and the character " 5)

Operation 45

3.8 Fast Continuous Transmission Protocol

This protocol allows for continuous serial output at high update frequencies. Up to 80 strings per second are transmitted (with a minimum transmission rate of 9600 baud). See “Filter Settings” on page 19 for limitations.

Following communication modes available (see Section 2.4 “Analog Output” on page 21):

• NOd t: communication compatible with TX RS-485 instruments;

• NOd td: communication compatible with TD RS-485 instruments.

•If NOd t is set, the following string is transmitted to PC/PLC: xxxxxxCRLF

in which:

xxxxxx = 6 ASCII characters for gross weight (48 ÷ 57 ASCII). CR = 1 character of carriage return (13 ASCII). LF = 1 character of line feed (10 ASCII).

In case of negative weight, the first character on the left acquires the value « - » (minus sign - ASCII 45).

In case of error or alarm, the 6 weight characters are replaced by the messages found in “Alarm Descriptions” on page 33.

•If NOd td is set, the following string is transmitted to PC/PLC:

&TzzzzzzPzzzzzz\ckckCR

in which:

& = 1 character of string start (38 ASCII). T = reference character for gross weight.

P = reference character for gross weight. zzzzzz = 6 ASCII characters for gross weight (48 ÷ 57 ASCII). \ = 1 character of separation (92 ASCII). ckck = 2 ASCII control characters calculated considering that the

characters between & and \ are excluded. The control value is obtained by

carrying out the XOR (or exclusive) operation for the 8 bit ASCII codes of the characters considered. A character expressed in hexadecimal is thus obtained, with 2 digits which may acquire values from “0” to “9” and from

“A” to “F”. “ckck” is the ASCII code of the two hexadecimal digits. CR = 1 character for string end (13 ASCII).

In case of negative weight, the first character on the left acquires the value « - » (minus sign - ASCII 45).

In case of error or alarm, the 6 gross weight characters are replaced by the messages found in “Alarm Descriptions” on page 33.

Fast Transmission Via External Contact: A single string can be transmitted by

closing a digital input, not exceeding 1 second. (see Section 2.6 “Outputs And

Inputs Configuration” on page 26 and Section 2.4 “Analog Output” on page 21).

3.9 Continuous Transmission Protocol To Remote Displays

Using this protocol, the instrument transmits, in continuous mode, the weight to remote displays; the communication string is transmitted 10 times per second. Following communication modes are available (see Section 2.4 “Analog Output” on page 21):

• rl P: remote display shows the net or gross weight, depending on the remote display setting.

46 SCT Weight Transmitter Operator’s Manual

• Hdrl P: remote display shows the net or gross weight, depending on the

Note

remote display setting.

• Hdrl Pn:

See next page for more information.

The instrument sends the following string to the remote display:

&NxxxxxxLyyyyyy

\ckckCR

in which:

& = 1 character of string start (38 ASCII). N = 1 reference character for net weight. (78 ASCII). xxxxxx = 6 ASCII characters for net or peak weight if present (48 ÷ 57

ASCII).

L = 1 reference character for gross weight (76 ASCII). yyyyyy = 6 ASCII characters for gross weight (48 ÷ 57 ASCII). \ = 1 character for separation (92 ASCII). ckck = 2 ASCII control characters calculated considering that the

characters between “&” and “\” are excluded. The control value is

obtained by carrying out the XOR (or exclusive) operation for the 8 bit ASCII codes of the characters considered. Character expressed in hexadecimal is thus obtained, with 2 digits which may acquire values from

“0” to “9” and from “A” to “F”. “ckck” is the ASCII code of the two

hexadecimal digits.

CR = 1 character for string end (13 ASCII).

In case of negative weight, the first character on the left acquires the value « - » (minus sign - ASCII 45).

If the protocol on Hdrl P has been set, the decimal point at the position shown on the instrument's display can also be transmitted. In this case, if the value exceeds 5 digits, only the 5 most significant digits are transmitted, while if the value is negative, no more than the 4 most significant digits are transmitted. In both cases, however, the decimal point shifts consistently with the value to display.

If Hdrl Pn has been set, in addition to what stated in Hdrl P protocol, the instrument transmits the prompt net every 4 seconds in the gross weight field, if the instrument is in the net mode (see Section 3.1 “Semi-Automatic Tare (Net/ Gross)” on page 32).

In case weight value is under -99999, the minus sign (‘-‘) is sent alternated with the most significant figure.

In case of error or alarm, the 6 characters of the gross and net weight are replaced by the messages found in “Alarm Descriptions” on page 33.

Operation 47

3.10 Communication Examples

The numerical data below are expressed in hexadecimal notation with prefix h.

Example 1

Command for multiple writing of registers (hexadecimal command 16, h10): Assuming that we wish to write the value 0 to the register 40017 and the value

2000 to the register 40018, the string to generate must be:

h01 h10 h00 h10

The instrument will respond with the string:

h01 h10

Query Field Name Hex Response Field Name Hex

Instrument Address h01 Instrument Address h01 Function h10 Function h10 Address of the first register H h00 Address of the first register H Address of the first register L h10 Address of the first register L h10 Number of registers to send H Number of registers to send L Byte Count h04 CRC16 H h40 Datum 1 H Datum 1 L Datum 2 H h07 Datum 2 L CRC16 H hF1 CRC16 L h0F

h00 h10 h00 h02 h40 h0D

h00 h02 h04 h00 h00 h07 hD0 hF1 h0F

h00

h00 Number of registers H h00 h02 Number of registers L h02

h00 CRC16 L h0D h00

hD0

48 SCT Weight Transmitter Operator’s Manual

Example 2

Command for multiple writing of registers (hexadecimal command 16, h10): Assuming that we wish to write the two setpoint values on the instrument, at

2000 and 3000 respectively, the string must be sent:

h01 h10

h00 h10 h00 h04 h08 h00 h00 h07 hD0 h00 h00 h0B hB8

hB0 hA2

The instrument will respond with the string:

h01 h10 h00 h10 h00 h04 hC0 h0F

Query Field Name Hex Response Field Name Hex

Instrument Address h01 Instrument Address h01 Function h10 Function h10 Address of the first register H Address of the first register L h10 Address of the first register L h10 Number of registers to send H h00 Number of registers H h00 Number of registers to send L h04 Number of registers L h04 Byte Count h08 CRC16 H Datum 1 H h00 CRC16 L h0F Datum 1 L Datum 2 H Datum 2 L hD0 Datum 3 H Datum 3 L Datum 4 H h0B Datum 4 L CRC16 H hB0 CRC16 L hA2

h00 Address of the first register H h00

hC0

h00 h07

h00 h00

hB8

Operation 49

Example 3

Multiple command reading for registers (hexadecimal command 3, h03): Assuming that we wish to read the two gross weight values (in the example

4000) and net weight values (in the example 3000), reading from address 40008 to address 40011 must be performed by sending the following string:

H01 h03

h00 h07 h00 h04 hF5 hC8

The instrument will respond with the string:

H01 h03 h08 h00 h00 hF hA0 h00 h00 h0B hB8 h12 h73

Query Field Name Hex Response Field Name Hex

Instrument Address h01 Instrument Address h01 Function h03 Function h03 Address of the first register H Address of the first register L h07 Address of the first register L h00 Number of registers to send H h00 Datum 1 H h00 Number of registers to send L h04 Datum 1 L h00 CRC16 H hF5 Datum 2 H h0F CRC16 L hC8 Datum 2 L hA0

h00 Address of the first register H h08

Datum 3 H Datum 3 L h00 Datum 4 H Datum 4 L CRC16 H h12 CRC16 L h73

h00

h0B hB0

For additional examples regarding the generation of correct control characters

(CRC16) refer to the manual Modicon PI-MBUS-300.

50 SCT Weight Transmitter Operator’s Manual

SCT Weight Transmitter Limited Warranty

Rice Lake Weighing Systems (RLWS) warrants that all RLWS equipment and systems properly installed by a Distributor or Original Equipment Manufacturer (OEM) will operate per written specifications as confirmed by the Distributor/ OEM and accepted by RLWS. All systems and components are warranted against defects in materials and workmanship for one year.

RLWS warrants that the equipment sold hereunder will conform to the current written specifications authorized by RLWS. RLWS warrants the equipment against faulty workmanship and defective materials. If any equipment fails to conform to these warranties, RLWS will, at its option, repair or replace such goods returned within the warranty period subject to the following conditions:

• Upon discovery by Buyer of such nonconformity, RLWS will be given

prompt written notice with a detailed explanation of the alleged deficiencies.

• Individual electronic components returned to RLWS for warranty

purposes must be packaged to prevent electrostatic discharge (ESD) damage in shipment. Packaging requirements are listed in a publication,

Protecting Your Components From Static Damage in Shipment,

available from RLWS Equipment Return Department.

• Examination of such equipment by RLWS confirms that the

nonconformity actually exists, and was not caused by accident, misuse, neglect, alteration, improper installation, improper repair or improper testing; RLWS shall be the sole judge of all alleged non-conformities.

• Such equipment has not been modified, altered, or changed by any

person other than RLWS or its duly authorized repair agents.

• RLWS will have a reasonable time to repair or replace the defective

equipment. Buyer is responsible for shipping charges both ways.

• In no event will RLWS be responsible for travel time or on-location

repairs, including assembly or disassembly of equipment, nor will RLWS be liable for the cost of any repairs made by others.

HESE WARRANTIES EXCLUDE ALL OTHER WARRANTIES, EXPRESSED OR

IMPLIED MERCHANTABILITY

RLWS NOR DISTRIBUTOR WILL, IN ANY EVENT, BE LIABLE FOR INCIDENTAL

CONSEQUENTIAL DAMAGES.

RLWS

HEREUNDER ACCEPTING CLAIMS

HOULD THE SELLER BE OTHER THAN RLWS, THE BUYER AGREES TO LOOK

ONLY

O TERMS, CONDITIONS, UNDERSTANDING, OR AGREEMENTS PURPORTING TO

MODIFY UNLESS AND THE BUYER.

, INCLUDING WITHOUT LIMITATION WARRANTIES OF

OR FITNESS FOR A PARTICULAR PURPOSE. NEITHER

AND BUYE R AGREE THAT RLWS’ SOLE AND EXCLUSIVE LIABILITY

IS LIMITED TO REPAIR OR REPLACEMENT OF SUCH GOODS. IN

THIS WARRANTY, THE BUYER WAIVES ANY AND ALL OTHER

TO WARRANTY.

TO THE SELLER FOR WARRANTY CLAIMS.

THE TERMS OF TH IS WARRANTY SH ALL HAVE ANY LEGAL EFFECT

MADE IN WRITING AND SIGNED BY A CORPORATE OFFICER OF RLWS

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WISCONSIN 54868 • USA

For More Information

Web Site

Frequently Asked Questions (FAQs)

•

http://www

Contact Information

Hours of Operation

Knowledgeable customer service representatives are available 6:30 a.m. - 6:30 p.m. Monday through Friday and 8 a.m. to 12 noon on Saturday. (CST)

Telephone

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For immediate assistance call toll-free 1-800-472-6703 (Canadian and Mexican customers please call 1-800-321-6703). If you are calling after standard business hours and have an urgent scale outage or emergency, press 1 to reach on-call personnel.

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• US

prodinfo@ricelake.com

• International (non-US) sales and product information at

intlsales@ricelake.com

Mailing Address

Rice Lake Weighing Systems 230 West Coleman Street Rice Lake, WI 54868 USA

on at

230 W. Coleman St. t Rice Lake, WI 54868 t USA

U.S. 800-472-6703 t Canada/Mexico 800-321-6703 t International 715-234-9171 t Europe +31 (0) 88 2349171

www.ricelake.com www.ricelake.mx www.ricelake.eu www.ricelake.co.in m.ricelake.com

Rice Lake SCT-10 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Contents

1.0 Introduction

1.1 Safety

1.1.1 Safety Symbol Definitions:

1.1.2 Safety Precautions

1.1.3 Equipment Recommendations

1.1.4 Correct Installation Of Weighing Instruments

1.1.5 Correct Installation Of The Load Cells

1.2 Load Cells

1.2.1 Load Cell Input Test (Quick Access)

1.2.2 Load Cell Testing

1.3 Specifications

1.4 Electrical Connections

1.5 LED and Key Functions

1.6 Instrument Commissioning

1.6.1 If The Instrument Has Not Been Calibrated

2.0 Configuration

2.1 Calibration

2.1.1 Theoretical Calibration

2.1.2 Maximum Capacity (NASS )

2.1.3 Zero Setting

2.1.4 Zero Value Manual Entry

2.1.5 Weight (Span) Calibration (With Test Weights)

2.1.6 Setting Units of Measure

2.1.7 Display Coefficient

2.2 Filter On The Weight

2.3 Zero Parameters

2.4 Analog Output

2.5 Serial Communication Settings

2.5.1 RS-485 Serial Communication

2.6 Outputs And Inputs Configuration

2.7 Test

2.8 Setpoints Programming

2.9 Reserved For The Installer

2.9.1 Default Scale

2.9.2 Program Selection - Reverse:

2.9.3 Keypad Or Display Locking

3.0 Operation

3.1 Semi-Automatic Tare (Net/Gross)

3.2 Preset Tare (Subtractive Tare Device)

3.3 Semi-Automatic Zero (Weight Zero-setting For Small Variations)

3.4 Peak

3.5 Alarms

3.6 Modbus-RTU Protocol

3.7 ASCII Bidirectional Protocol

3.8 Fast Continuous Transmission Protocol

3.9 Continuous Transmission Protocol To Remote Displays

3.10 Communication Examples

SCT Weight Transmitter Limited Warranty

For More Information