Modbus RTU/TCP Master module located in the Connection Manager and used for communicating with Modbus protocol supported devices as Master.

                                                                                                                                                               Modbus RTU/TCP Master
Modbus RTU Networks connected to computer through Com ports. Therefore maximum Network count is determined by Com port count on the computer.

Maximum Modbus TCP Network count is 127.
Can not connected to same device from different networks at same time.
Creating a new Network
Creating a Tag
Tag List Menu
Grup Cycle Belirlenmesi
Delete, removes group.
Deleting a group
Status Strip
40001 Unsigned int 16
40002 Singned int 32
40004 Floatpoint
40006 Signed int 16
40007 Unsigned int 32

Query Byte Count:
1 Query:16 Byte
40001 Unsigned int 16
40001 Singned int 32
40003 Floatpoint
30005 Signed int 16
30006 Unsigned int 32

Query Byte Count:
1st Query : 2 Byte
2nd Query: 8 Byte
3rd Query: 6 Byte
Boolean
0 or 1
Usigned int16
0 to 65535
Signed int16
-32768 to +32767
Unsigned int32
0 to 4294967295
Signed int32
-2147483648 to +2147483647
Floatpoint
32-Bit Named as Single as well.
BCD
Binary-Coded Decimal
Long BCD
Long Binary-Coded Decimal
Time of Day
Time of day. Day can not be used in this type.
Date
Word defined Day number. Beginning of date is "1.1.1990".
Tag List
Data type table
Modbus RTU/TCP Master Tab
WinTr can connect multiple Modbus Networks through different serial ports as a Master. Thus it is not required to all PLCs located in the same network. In this way, increasing PLC count has no effect on communication speed.

In Modbus RTU protocol, connection is made over serial lines and maximum connected RTU Network count is the number of serial ports on the computer. Com port count can be extended by USB-Serial converters. Networks read and written asynchronously but Slave Modbus stations read and written sequently by their addresses.

In Modbus TCP protocol, connection is made over ethernet line using TCP/IP. Maximum 127 network can be connected same time. Networks read and written asynchronously but Slave Modbus stations read and written sequently by their addresses.




According to Modbus protocol, one Network can contain maksimum 247 slave device. This devices read and written sequently by their addresses.

Device addresses are located in the devices and they assigned by programmer as unique addresses.

Newly Created Network
Newly Created Network
Sample application scheme
Network menu
Properties, displays Properties window which contains Network connection settings.

Connection type is determined in this window's Select Communication Method section as a RTU or TCP.

Network menu - Network group
Modbus RTU communication settings
Deleting a Network
Adding a new station
Station menu
Properties, displayes a Station Properties window which contains settings about the station.
This group has only Add command for creating a new group.
İstasyon menu - Station group
Adding a Group
Grup menu
Determining group's name
Name, determines group's name.
Deleting a Network
Creating a new Network
Sample application scheme
Deleting a Network
Network menu
Network menu - Network group
Modbus RTU communication settings
Modbus RTU connection settings:

Serial Port, determines the serial port that will use for the Network connection.

Baudrate, Parity, Stop Bit and Flow Control are settings for the serial communication.

Poll Interval, determines period of the queries that send to PLC. This value ignored while writing data to PLC. Data is written to PLC immediately at the time of the command executed.

Time Out, waiting period for the establishing a connection.


Deleting a Network
Adding a new station
Station menu
İstasyon menu - Station group
Station Properties
Station Name, determines station's name in the SCADA.

Station Address, address for the connected station.

Fail Repeated Queries, determines repeating count of the query for failed communications.

Function Code 6 Enable, some PLC's don't use Function Code 6 for writing operations. This option determines if Function Code 16 will be used for completing this task.

32 Bit Data Word Order: 32 bit data made up by 2 unit 16-bit Word. In order to represent a same number with this data at two end of the connection, both side should evaulate same words as High and Low Order.
This section determines which Word will be evaluated as High and Low Order..

Discrete Max. Block Size: In Modbus protocol, 8 to 2000 bits can be read at once. But for some PLCs amount could be smaller. This setting determines maximum packet size to read at once.

Analog Max. Block Size:  In Modbus protocol, 1 to 125 register can be read at once. But for some PLCs amount could be smaller. This setting determines maximum packet size to read at once.

Station Properties
Grup menu
Adding a Group
Grup Cycle Belirlenmesi
Determining group's name
Deleting a group
Tag List
Groups that created in the station and Tags that balong to group
Tags that belong to station
Creating a Tag
Deleting a Tag
Tag List Menu
WinTr Connect button
WinTr Connect button
Modbus RTU/TCP Master Connect button
Modbus RTU/TCP Master Connect button
Notifying PLC Tags that can not be accessed
Writing a value to PLC
40001 Unsigned int 16
40001 Singned int 32
40003 Floatpoint
40005 Signed int 16
40006 Unsigned int 32

Query Byte Count:
1st. Query:2 Byte
2nd Query:14 Byte
Query byte count scheme
Creating a New Network:
In Modbus RTU/TCP Master tab, when right mouse button clicked in the white area at the left, a little menu box opens. A new Network is created by clicking Add in this menu. Being RTU or TCP of this Network will be determined later.
Deleting a Network:

When right clicked on the Network, a menu opens. Selecting Delete in this menu will delete the Network.
Additionally, Network can be deleted from the Network Menu as described at bottom.
When right clicked on Network, a menu opens which contains Network and Station groups.
Network Menu
Network Menu - Network Group:

Network group made up by two item as Properties and Delete.
Delete command in the Network menu Deletes the Network.
Network Menu - Station Group:

Station group, that in the Network's right click menu, contains Add command which adds a station inside the Network.
Station Menu:
When right clicked on the station, a menu opens which contains Station and Group groups.
Station Menu - Station Group:

Contains two element as a Properties and Delete.
Station Menu - Group Group:

Groups:

Tags are created in Groups.
Maximum 128 group can be created.
Groups are created for improving communication performance.
By creating Tags in different groups, some Tags can be read at each cycle, some Tags can be read rarely according to specified group cycle parameter.
In this way some PLC values can be read quick, some values can be read slow.
Grup Menu:

When right clicked on the Group, Group Menu opens which allows group related operations.
Cycle, determines group's read period in cycle.
In Group Menu;
Tag List:

The list at the right side which contains created tags.
The Tags that read and write to PLC are created in this list. Additionally Tag values can be monitored and set in this list.

Group must be selected to adding or deleting Tags in this list.

If group not selected, Tag values can be monitored or set but Tags can not be added or deleted. 

By selecting the group, only the tags, which belongs to that group, are listed.
Groups that created in the station and Tags that belong to group
All Tags will be listed when Station selected.

When Network selected the Tags listed which belongs to last selected group or station.

Tags that belong to station
Tag Creating and Deleting Operations:
Bottom line of the Tag List will be ready for the creating Tag after selecting the group.

Adress Column: Tag's address inside the PLC should be entered this in column. The Tag which will read and write to register will be created by pressing Enter key after typing register address.
Tag Name Column: Each newly created Tag will be named with a unique name. This name can be changed by user with another unique name.



Value Type Column: Tag's data type determined in this column. All types read and transferred to PLC in Modbus format. But they are displayed in Windows standart.


Displayed Data Types:
In Tag list, Rows can be selected by clicking on left side title of the Row. Multiple Rows can be selected by pressing Ctrl key while selecting rows or dragging the mouse.

Selected rows can be deleted by pressing Delete key on the keyboard or selecting Delete command from the right click menu on the related row.
Tag List Menu
Deleting a Tag
Tag List menu opens when right mouse button clicked on Tag List.
On Tag List menu;

Insert, inserts new Tag above the selected Tag.

Cut, cuts selected row or rows.

Copy, copies selected row or rows.

Paste, pastes copies or cut tags.

Delete, deletes selected row or rows.

Monitoring and Setting Tag Values

Tag values that inside the PLC can be monitored and set in this tab. Network connection must be activated to do this.

Activating Network Connection

Created Network connection can be activated by clicking on Connect button that located in the Modbus RTU/TCP Master toolbar or by clicking Connect button on the WinTr toolbar.
Activating Networks
Activating Networks
Connect Button that located on WinTr Toolbar activates all Networks.
Connect button on the Modbus RTU/TCP Master tab activates only selected Network.
Tag values will be read from PLC adresses and shown in the Read Value column in both connection types.

The PLC variables that can not be accessed for any reason will be notified with the red background.
Notifying PLC Tags that can not be accessed
To write a PLC, value must be entered to related row's Write Value column then pressed Enter key on the keyboard.

Writing a value to PLC
Disconnecting Network

If all networks activated by Connect button on the WinTr toolbar, all network connections will be disconnected if pressed again same button.
If Disconnect button pressed that on the Modbus RTU/TCP Master tab's toolbar, network will be disconnected just for a time then it will reactivated immediately.

If Network connection activated by Connect button on the Modbus RTU/TCP Master tab, next Disconnect button will only deactivate that network.



Disconnecting the Network
Disconnecting the Network
Status Strip:

StatusStrip that locates bottom of the Modbus RTU/TCP Master tab, contains information about Network connection.
First information in this group is Tag Count.
Good is the number of successul communication since Network has been activated.
Bad indicates failed communication count.

Query Byte Count: Most important information of this group. Query is calculated according to entered variable addresses. Then it is sent to PLC. According to calculated query, the byte count that PLC should sent is shown here.

WinTr tries to read all Tags in the group at once. If entered addresses are sequental, all list read at once. In WinTr, maximum 250 byte can be read at once for  Modbus RTU/TCP Master standart. Calculated query size is shown as the Query Byte Count in the Statusstrip. If you see different count than you estimated, there could be an error.


Adjusting Query Byte Count for Best Performance:

Query Byte Count should be maximum to get high performance. For example we have 16 byte data communication in our Network. Communication performance will be change according addresses to be read .

If 16 byte is reached sequentally, communication performance will be maximum. In this case Query Byte Count will indicate 16.

If same bytes are reached repeatedly, this will cause negative effect on communication performance.
Gap between the bytes that will read has negative effect on communication performance also.
Following 2 illustarations showing lower performance communication.
Modbus is widely used industrial communication protocol which is supported by most of the PLC's(even some sensors). Data is transferred between Master and Slave stations, which makes queries and which answers them respectively.
Entering Addresses in Hex representation
Entering Addresses in Hex representation
Addresses can be entered in Hex representation by putting "h" at beginning. For example decimal 40001 address value can be entered in hex h9c41. Wintr will  convert address to decimal representation automatically.
For serial communication, Modbus RTU, for ethernet communication Modbus TCP version is used. This page explains how to use WinTr SCADA as a Master station in Modbus RTU and Modbus TCP communications.
Master and slave stations on modbus network
Modbus RTU/TCP Master Tab
Status Strip
Adjusting Query Byte count
Query byte count scheme

                                                                                                                                                                               English                Turkish
Modbus Addresses:

In Modbus standart, 2 type variable as a Bit and 16-Bit Word are addressed in the 4 table. Following table shows table addresses and read-write permissions.

Each variable expressed by a Data Address between 0 and 9998 (for Output holding Registers 0-25534) inside it's Table.
For example first variables of the 4 tables has 0 Data Address. Variable's unique address determined by adding table's starting addresses(1, 10001, 30001 and 40001) to this number as an offset.

The register addresses in the device datasheets may refer to Output Holding Registers. So WinTr tags should be created for the addresses which is sum of the 40001 and given address number.
If device datasheet indicates that temperature value located in the address 100, first it should be determined that value is decimal or hex representation.

If 100 is decimal representation, WinTr tag should be created for the address 40101 (40001+100).
If 100 is hex representation, decimal equivalent 256 should be added to 40001 and WinTr tag should be created for the address 40257 (40001+256).

Address Range:
1-9999
10001-19999
30001-39999
40001-65535
Data Size:
1 Bit
1 Bit
16-Bit Word
16-Bit Word
Permission:
Read-Write
Read Only
Read Only
Read-Write
Table Name:
Output Coils
Input Contacts
Input Registers
Output Holding Registers
Data Address:
0-9998
0-9998
0-9998
0-25534
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