CARLO GAVAZZI RSGD User manual

RSGD 75mm
Modbus Protocol
Rev 2.0

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Contents
Chapter 1 Introduction
1.1 Foreword...............................................................................................................................3
1.2 Product inspection.................................................................................................................3
1.3 Precautions ...........................................................................................................................3
Chapter 2 Software Installation
2.1 System requirements.............................................................................................................4
2.2 Software setup file.................................................................................................................4
2.2 Installing the software............................................................................................................4
2.3 Uninstalling the software........................................................................................................6
Chapter 3 Establishing Communication
3.1 Introduction............................................................................................................................7
3.2 Installation.............................................................................................................................7
3.3 One-to-one communication.....................................................................................................8
3.4 One-to-many communication..................................................................................................9
3.5 Automatic Connection .........................................................................................................10
3.6 Manual Connection..............................................................................................................11
Chapter 4 SCS User Interface
4.1 Software structure ...............................................................................................................12
4.2 Toolbar icons.......................................................................................................................12
4.3 Dashboard window..............................................................................................................12
4.4 Settings window ..................................................................................................................20
4.5 Variables window.................................................................................................................24
Chapter 5 Modbus RTU Protocol
5.1 Introduction..........................................................................................................................28
5.2 Modbus RTU functions........................................................................................................28
5.3 Registers Map.....................................................................................................................30
Chapter 6 Examples
6.1 Changing the communication parameters............................................................................37
6.2 Start/Stop through Modbus...................................................................................................38
6.3 Start/Stop using Force RefreshSignal ..................................................................................39
Appendix
History File................................................................................................................................41

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Chapter 1 Introduction
1.1 Foreword
RSGD is a 2-phase controlled soft starter with a dedicated algorithm for
general purpose applications. RSGD is equipped with Modbus RTU
communication over RS485.
The purpose of this document is to outline information on the functionalities
that are provided by Modbus. Modbus can be used to initialise, control and
monitor RSGD general purpose soft starters. Should there be any problems
that cannot be solved with the information provided in this guide, contact our
technical representative who will be willing to help you.
1.2 Product
inspection
Please check the following when receiving and unpacking RSGD units:
•The product is the one specified in your purchase order
•Check if there are any damages caused by transportation. In case
of any problem, do notinstall the product and contact Carlo Gavazzi
sales representative.
We suggest keeping the original packing in case it is necessary to return the
instrument to our After Sales Department. In order to achieve the best results
with your product, we recommend reading the instruction manual carefully. If
the product is used in a way not specified by the producer, the protection
provided by the product may be impaired.
1.3 Precautions
For your safety, thefollowing symbol is to remind you to pay attention to safety
instructions on configuring and installing RSGD. Be sure to follow the
instructions for higher safety.
This symbol indicates a particularly important subject or information
Please read this manual thoroughly before using the device. Should there be
any problem using the product which cannot be solved with the information
provided in the manual, contact your nearest Carlo Gavazzi distributor or our
sales representatives to help you. Check that the device is installed in
accordance with the procedures as described in this manual.
The manufacturer accepts no liability for any consequence resulting from
inappropriate, negligent or incorrect installation or adjustment of the optional
parameters of the equipment. The contents of this guide are believed to be
correct at the time of printing. In the interests of commitment to a policy of
continuous development and improvement, the manufacturer reserves the
right to change the specification of the product or its performance, or the
content of the guide without notice.

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Chapter 2 Software Installation
2.1 System
requirements
Software configuration software is designed to run on:
•Windows 7
•Windows 8/8.1
•Windows 10
2.2 Software
setup file
If the PC meets the above system requirements, you can download the latest
version of the setup_SCS_2.0.zip from our website
(http://gavazziautomation.com/nsc/HQ/EN/soft_starters).
2.2 Installing the
software
If the setup file is downloaded successfully, you can start installing the software
by unzipping the file and then run the setup.msi file. The following window will
appear:

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Click next to progress through the Install Wizard and install the Soft Starters
Configuration Software.
Choose a location to install the software or click next to continue with the default
location.
Click next to start the installation.
Once the installationis complete, you should see the Carlo Gavazzi logo on your
desktop. Double click to open the software. The following screen will appear:

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2.3 Uninstalling
the software
When you uninstall the software, the files installed by SCS will be removed from
your PC.
The following steps instruct you to uninstall the software from your PC.
➢Open the Control Panel in Windows and under Programs, click on
Uninstall a program
➢Select the software configuration software and click on Uninstall

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Chapter 3 Establishing Communication
3.1 Introduction
The RSGD can be controlled either by a PC or by a controller using Modbus
RTU protocol, with one-to-one or one-to-many communication. The Modbus
link between the master and slaves can be established on a 3-wire RS485
communication port.
The RSGD soft starters leave the factory with default communication
parameters as listed below:
Default communication parameters
Parameter
Default Value
Device address
1
Baud rate
9600
Parity
No parity
Stop Bit
2
The factory default communication parameters can be modified.
3.2 Installation
In order to be able to establish communication between a PC (or a controller)
and the RSGD, you will need to connect a raw cable between the
communicating device and the screw terminal type terminal box available on
the RSGD unit.
The A (-) and the B(+) connections from the soft starter need to be connected
to the Rx- (A) and Rx+ (B) line of the communicating device respectively. If this
connection is not followed, communication is not established.
To reduce noise on the RS485 communication raw cable, use a
twisted pair and shielded cable. In addition, connect the shield to the
GND terminal to further minimize the noise on the RS-485 cable.
A (-)
B (+)
GND
Rx –(A) Data (-)
Rx + (B) Data (+)
GND
RS485 to RS232
RSB….CVC

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3.3 One-to-one
communication
One-to-one communication occurs between a PC with SCS (or a controller) and
one RSGD.
In order to establish one-to-one communication, the RSGD unit must
be first powered-up with the specified supply voltage.
If the supply LED is green fixed on the soft starter, you can establish
communication with the soft starter.
The software provides two methods to establish one-to-one communication:
a. Automatic connection (more details in section 3.5)
b. Manual connection (more details in section 3.6)

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3.4 One-to-many
communication
One-to-many communication occursbetween a PC (or a controller) andmultiple
general purpose soft starters.
In order to establish one-to-many communication, the RSGD units
must be first all powered-up with the specified supply voltage.
If the supply LED is green fixed on the soft starter, you can establish
communication with the soft starter.
The software provides two methods to establish one-to-many communication:
a. Automatic connection (more details in section 3.5)
b. Manual connection (more details in section 3.6)
For one-to-many communication, the device address of each RSGD
should be different.
For one-to-many communication, the baud rate and parity bit of each
RSGD should be the same.
For large networks, it is required to place a 120Ω ¼W resistor
between A (-) and the B(+) connections on the last soft starter, to
avoid possible communication problems.

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3.5 Automatic
Connection
The automatic connection is useful when the communication parameters
mentioned in Section 3.1 are unknown.
The following procedure must be followed to establish communication:
➢Select the serial port that you will be using on the PC
➢Click on the Connect icon
The software starts to find all the devices attached to the serial port.
If connection is successful, the following window will appear if you have
established communication:
In the event that communication is not established, the following message will
be displayed:
Please check that the following conditions are satisfied before trying to re-
establish communication:
✓RSGD softstarter/s is/are powered-up (Green fixed LED)
✓RS485 port is properly connected
✓Communication settings are correct

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3.6 Manual
Connection
Themanual connectionis used when the communication parameters mentioned
in Section 3.1 are known.
The following procedure must be followed to establish communication:
➢Click on the Connect icon
➢Enter the relevant communication parameters and click on the Connect
icon
If connection is successful, the following window will appear if you have
established communication:
In the event that communication is not established, the following message will
be displayed:
Please check that the following conditions are satisfied before trying to re-
establish communication:
✓RSGD softstarter/s is/are powered-up (Green fixed LED)
✓RS485 port is properly connected
✓Communication settings are correct

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Chapter 4 SCS User Interface
4.1 Software
structure
The soft starter configuration software can be used to configure, control and
monitor RSGD soft starters. It consists of three main windows:
•Dashboard
•Settings
•Variables
The three main windows of the SCS can only be accessible when
the PC establishes communication with the device.
4.2 Toolbar icons
The user interface has different icons in the toolbar in order to choose among
the main windows of the software.
Toolbar icons
Icon
Description
Open the Dashboard window
Open the Settings window
Open the Variables window
Navigate to a previously viewed window
Disable live preview
4.3 Dashboard
window
The Dashboard window is the main screen of the soft starter configuration
software. This window can be used to select the soft starter that you want to
work with when having one-to-many communication. Furthermore, it provides
several functions which are designed specifically to control and monitor the
selected device.

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The functions provided by the Dashboard window are:
a. Device
This function consists of:
➢Device On/Off command
This command can be used to switch On/Off the control/start
signal, if the Control Mode is set to Modbus control.
The Control Mode parameter can be modified
through the software from the Settings windowunder
the Inputs section.
If this command is ON, as soon as the soft starter
resets from an alarm, the load will switch ON.
➢Refresh command
When Start Command Refresh is enabled, the soft starter
expects a Refresh command to be sent within the Refresh
Interval that canbe set by the user. If this commandis not sent
during the Refresh Interval, then the soft starter assumes that
communication has been lost and will switch OFF the load.

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The Start Command Refresh and Refresh Interval
parameters can be modified through the software
from the Settings window under the Inputs section.
➢Number of ramps
This variable indicates the number of ramps (i.e. the number
of starts) that the soft starter has successfully accomplished.
➢Status of Alarm Relay
This variable indicates whether or not the soft starter is in
alarm condition.
➢Status of Top of Ramp Relay
This variable indicates whether or not the soft starter is in
bypass mode.
➢Status of Run Relay
This variable indicates whether or not the soft starter is in run
mode.
b. Device Status
This function consists of:
➢Soft Starter Status
The status of the soft starter can be:
✓IDLE
✓RAMP-UP
✓BYPASS
✓RAMP-DOWN
✓ALARM
✓RECOVERY
The soft starter will not respond to a start command
if it is in Alarm or Recovery state.
➢Control Mode
The control mode can be:
✓A1-A2
✓MODBUS

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➢Alarm Reset
The alarm reset mode can be:
✓AUTO
✓MANUAL
➢Motor Overload Alarm & Phase Sequence Alarm
The motor overload and phase sequnce can be:
✓ENABLE
✓DISABLE
➢Remote Reset & PTC
The remote reset and PTC can be:
✓OPEN
✓SHORT
c. Voltage & Current Monitoring
This function monitors either one of the following variables:
➢Line-to-Line voltage (V)
➢Line current (A)
To select between the aforementionedvariables, youmust click on the
upper right-hand corner of the widget and the following screen will
appear:

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d. Power Monitoring
This function monitors either one of the following variables:
➢Frequency (Hz)
➢Active power (kW)
➢Total apparent power (kVA)
➢Reactive power (kVAr)
➢Power factor (PF)
➢Power (kWh)
To select between the aforementionedvariables, youmust click on the
upper right-hand corner of the widget and the following screen shall
appear:
e. Temperature Monitoring
This function monitors either one of the following variables:
➢Thermal capacity used (%)
➢NTC temperature (oC)
➢Junction temperature (oC)
➢Virtual motor temperature (oC)

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To select between the aforementioned variables, you must click on
the upper right-hand corner of the widget and the following screen
shall appear:
f. Scope
This function works the same way as an oscilloscope and it can
monitor either one of the following variables:
➢Line-to-Line voltage (V)
➢Line current (A)
To select between the aforementionedvariables, youmust click on the
upper right-hand corner of the widget and the following screen will
appear:

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g. Alarm Status
If one of the eight alarms mentioned in Variables window is triggered
the following screen will appear:
The softstarter will not respond to a start command if it is in
Alarm state.
h. Sales/Engineering
The following variables and settings are password protected:
➢Junction Temperature (oC)
➢Virtual Motor Temperature (oC)
➢Supply Voltage Unbalance (%)
➢Over Voltage Supply Limit (%)
➢Under Voltage Supply Limit (%)
➢Load Current Unbalance Limit (%)
➢Imax Bypass (A)

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To unlock these variables and settings, you must enter the correct
access code.
The access code can be obtained from Carlo Gavazzi sales
support.
If theaccesscodeis incorrect,thefollowingmessage will be displayed:

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4.4 Settings window
The Settings window lists the programmable parameters available for the
RSGD units. If you want to customise the unit for your own application, you
will have to change the default factory parameter settings.
Make sure that the RSGD isin idle state while parameters aremodified.
The functions provided by the Settings window are:
a. Delays
This function contains the delays related to stop-to-start and start-to-
start intervals that can be modified by the user. The user can also
visualise the time from last stop and time from last start.
It is up to the user to make sure that the maximum starts/hr
that the RSGD unit can handle is not exceeded.
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