I/O Communication Wonderware InTouch
Historical Trend Wonderware Intouch:-https://youtu.be/tf_KmkBpKyg
Configuring Real-time Trends Wonderware InTouch :-https://youtu.be/UbDIdU8ggJ4
- Explain I/O Communication Configuring Wonderware InTouch Protocols
- Explain and configure an InTouch Access Name
- This section explains I/O Communication Configuring Wonderware InTouch protocols and demonstrates how to configure an InTouch access name.
Dynamic Data Exchange (DDE)
Dynamic Data Exchange (DDE) is a communication protocol developed by Microsoft to allow applications in the Windows environment to send/receive data and instructions to/from each other. It implements a client server relationship between two concurrently running applications.
The server application provides the data and accepts requests from any other application interested in its data. Requesting applications are called clients. Some applications such as InTouch and Microsoft Excel can simultaneously be both a client and a server.
Wonderware SuiteLink
Wonderware SuiteLink uses a TCP/IP-based protocol. SuiteLink is designed specifically to meet industrial needs, such as data integrity, high-throughput, and easier diagnostics. This protocol standard is supported for Windows 2000, Windows 2003 Server, and Windows XP.
SuiteLink is Not a Replacement for DDE. Wonderware recommends that DDE be used for internal client communication and SuiteLink for communication over the network.
Each connection between a client and a server depends on your network situation.
SuiteLink provides the following benefits:
Consistent high data volumes can be maintained between applications, regardless of whether the applications are on a single node or distributed over a large node count.
Value Time Quality (VTQ) places a timestamp and quality indicator on all data values delivered to VTQ-aware clients.
Extensive diagnostics of the data throughput, server loading, computer resource consumption, and network transport are made accessible through the Microsoft Windows NT® operating system performance monitor. This feature is critical for the scheme and maintenance of distributed industrial networks.
The network transport protocol is TCP/IP using Microsoft’s standard Winsock interface. To use the SuiteLink Communication Protocol, the following conditions must be satisfied. z You must have Microsoft TCP/IP configured and working properly.
You must use computer names (Node Names) of no more than 15 characters. For more information on installing and configuring Microsoft TCP/IP, see your Microsoft Windows operating system’s documentation.
Wonderware SuiteLink must be running as a service. If for some reason SuiteLink has been stopped, you will need to start it again. (SuiteLink is automatically installed as a Common Component when you install InTouch. It is configured to start up automatically as a Windows Service).
InTouch I/O Addressing
InTouch identifies an element of data in an I/O Server program by using a three-part naming convention that includes the application name, topic name, and item name. To obtain data from another application, the client program (InTouch) opens a channel to the server program by specifying these three items.
In order for InTouch to acquire a data value from another application, it must also know the name of the application providing the data value, the name of the topic within the application that contains the data value, and the name of the specific item within the topic. In addition, InTouch needs to know the data’s type: discrete, integer, real (floating point), or message (string).
This information determines the I/O type for the tagname when it is defined in the InTouch database. When WindowViewer is running, it will automatically perform all of the actions required to acquire and maintain the value of this item.
For example, in the case of Excel, the application name is “Excel,” the topic name is the name of the specific spreadsheet that contains the data and the item name is the identification of the cell on the spreadsheet to/from which the data is to be read/written.
When another Windows application requests a data value from InTouch, it also must know the three I/O address items.
The following describes the I/O address convention for InTouch.
VIEW (application name) identifies the InTouch Runtime program that contains the data element.
TAGNAME (topic name) is the word always used when reading/writing to a tagname in the InTouch database.
ActualTagname (item name) is the actual tagname defined for the item in the InTouch Tagname Dictionary.
For example, to access a data value in InTouch from Excel (running on the same node), a DDE Remote Reference formula would be entered in the cell into which the data value is to be written:
=VIEW|TAGNAME!’ActualTagname’
InTouch Access Names
When you create I/O-type tags or remote tagname references, they must be associated with an Access Name. Access Names contain the information that is used to communicate with other I/O data sources including the node name, application name and topic name.
Create an Access Name
Note: All I/O Server setup which follows is specific to the Wonderware facility training environment. Your instructor will provide the proper configuration information.
Note: The Access Name configured in the following steps is used in the subsequent lab.
Expand Configure in the Application Explorer.
Right-click Access Names and select Open.
Note: Access Names can also be created while you are defining an I/O-type tag in the Tagname dictionary.
The Access Names dialog box appears:
Click Add.
The Add Access Name dialog box appears:
Access Name: Enter the new Access Name
(For simplicity, use the same name that you will use for the topic name.).
InTouch uses Access Names to reference real-time I/O data. Each Access Name equates to an I/O address, which can contain a Node, Application, and Topic. In a distributed application, I/O references can be set up as global addresses to a network I/O Server or local addresses to a local I/O Server.
Node Name: Used when the data is from a remote I/O Server over the network.
Application Name: Enter the actual program name for the I/O Server program from which the data value will be acquired. If the value is coming from a Wonderware Modbus I/O Server, MODBUS is used. Do not enter the .exe extension portion of the program name.
Topic Name: Enter the topic name to access. The Topic Name is an application-specific sub-group of data elements.
In the case of data coming from a Wonderware I/O Server program, the topic name must be the exact same name defined in the I/O server.
Which Protocol to use: Select DDE (internal) or SuiteLink (network).
When to advise server:
Advise all items: Select if the server program is to poll for all data whether or not it is in visible windows, alarmed, logged, trended or used in a script. Selecting this option will impact performance and is not recommended.
Advise only active items: Select if the server program is to poll only points in visible windows and points that are alarmed, logged, trended or used in any script. A Touch Pushbuttons action script will not be polled unless it opens in a visible window.
The following figure shows an example of a completed access name (if the I/O server is on the local node, the Node Name: can be left blank as shown in the following figure).
Click OK to accept the new Access Name.
Click Close to close the dialog box.
Modifying or Deleting an Access Name
In the InTouch Application Explorer, right-click Access Names and select Open.
The Access Names dialog box appears:
Click Details.
Click New to add a new tagname.
In the Tagname field, enter a name for the new tagname.
Click Type.
The Tag Types dialog box appears:
Select I/O Integer for this tag.
Click OK. The respective details dialog box will be visible in the Tagname Dictionary. (If the details portion of the dialog box does not open, click Details at the top of the screen.)
Specify all the required details for defining the item.
Click Access Name.
The Access Names dialog box appears:
Select the access name to modify.
Click Modify.
The Modify Access Name dialog box appears.
Make any changes and click OK.
Repeat this procedure if you need to modify other Access Names.
To delete an Access Name, select it in the list and then click Delete.
A message box will open asking you to confirm the deletion. Click Yes.
Click Close or repeat this procedure to delete other defined Access Names. Note: Access Names used by tags cannot be deleted.
Defining an I/O Type Tagname
All I/O type tags receive their values from other Windows application programs such as Excel and I/O Servers. This value is referred to as the “raw” value. When you define a tag in the Tagname Dictionary, you must enter values for the Min– and Max Raw. These values are used by the database as clamps on the actual raw value received from the I/O device. For example, if you set the Min Raw value to 50 and the actual value received from a I/O Server is 0, database will force the Raw value to 50.
InTouch does not display raw values. Instead, it displays engineering units (EU) . When you define an I/O type tag in the Tagname Dictionary, you must specify values for the Min – and Max EU. These values are used to scale the raw value to the displayed value. If you do not want to do scaling or your I/O device does the scaling for you, set the Min/Max EU values equal to the Min/ Max Raw values.
For example, assume that a flow transmitter wired to a PLC register generates a value of zero at no flow and a value of 9999 at 100% flow. The following values would be entered:
Min EU = 0 Max EU = 100
Min Raw = 0Max Raw = 9999
A raw value of 5000 would be displayed as 50.
Assume that a flow transmitter wired to a PLC register generates a value of 6400 at no flow and a value of 32000 at 300 GPM.
Min EU = 0 Max EU = 300
Min Raw = 6400Max Raw = 32000
In this case, a raw value of 12800 would be displayed as 150. A raw value of 6400 would be displayed as 0 and a Raw value of 0 would be displayed as 0 (all values outside the boundaries set by the Min Raw and Max Raw values are clamped).
The above scaling works in reverse when the I/O tag data is written from the InTouch Tagname Dictionary to other Windows applications.
Press Ctrl+T.
The Tagname Dictionary dialog box appears:
Double-click the Access Name to use or select it and click Close. In the previous figure, the PLC1 access name is selected for this tag. The selected Access Name (now associated with this tag definition) appears adjacent to the Access Name button in the details portion of the Tagname Dictionary (shown next). In the Item Box, enter the item name or number for the data value in the IOServer application, PLC, or associated application. If the Item name is to be the same as the tagname, check the Use Tagname as Item Name box to automatically fill in the Item name. Note: Understand that the “tagname” is the name used within InTouch to refer to a data value (tag). The Item is the name used by a remote Windows application to refer to the same value. These names do not have to be the same, but it is recommended to use the same names.
Click Close.
Note: The Type field can be changed after adding the Item, until it is assigned to an Animation link or used in a script.
Wonderware I/O ServersSection Objective
Configure a Wonderware I/O Server (Modbus) This section will describe the configuration of a Wonderware I/O Server (Modbus).
Introduction
Wonderware I/O Servers are Microsoft Windows application programs that enable other DDE-aware Windows applications (such as InTouch or Excel) access to data in the real world (such as PLCs or RTUs). Wonderware servers are primarily intended for use with Wonderware’s InTouch program; however, they can be used by any Microsoft Windows program capable of acting as a DDE client. In this section, we will examine the start -up, configuration and use of a Wonderware I/O Server. Because Wonderware’s I/O servers are Windows applications, they will all have the same basic appearance and capabilities. Keep in mind that depending on server required, additional hardware (network, and so on) may be necessary and the configuration screens may require additional information. The following information references the Modbus I/O Server as a point- to-point server using the RS-232 serial port to PLCs provided at the Wonderware facility training environment. Your instructor may have you configure the following screens differently.
Note: All I/O Server setup which follows is specific to the Wonderware facility training environment. Your instructor will provide the proper configuration information. It accesses one Koyo DirectLogic O5 PLC via its programming port.
Configuring I/O Servers
Once the I/O Server has been installed, some configuration is required. Configuring the server automatically creates a configuration file named MODBUSDV.CFG. This file stores the configuration information about communication ports and all of the topic definitions (described in detail later). The configuration file is automatically saved to the directory in which the I/O Server is installed unless a different directory is specified via the
Configure / I/O Server Settings command.
Select Start / Programs / WonderwareFactorySuite / IOServers / Modicon MODBUS.
The MODBUS dialog box appears:
Click Configure / Com Port Settings.
The Communication Port Settings dialog box appears.
This dialog is used to configure the communication port that will be used to communicate with the PLC equipment.
Com Port: Select the communication port that is connected to the PLC equipment.
Reply Timeout: Enter the amount of time (in seconds) that all PLCs connected via this serial communications port will be given to reply to commands from the I/O Server.
Note: This timeout is sustained only when the PLC fails to respond. When the PLC is responding normally, there is no penalty. The default value of 3 second should be sufficient for most configurations.
Protocol area: Select the protocol configured for the equipment attached to this communication port. RTU is recommended.
Baud Rate area: Select the baud rate (serial bit rate) setting that matches the equipment connected to this communication port.
Data Bits area: Select the option for the number of data bits that corresponds to the configuration of the equipment on this communication port. If ASCII is selected for the protocol, use 7. If RTU is selected, use 8.
Stop Bits area: Select the appropriate number of stop bits for the communication port. If the baud rate is greater than 300, the stop bits should be set to 1.
Parity area: Select the setting that corresponds to the configuration of the equipment on this communication port.
Note: All devices on a single communication port must be configured with the same Protocol, Parity, Stop Bits, Data Bits and Baud Rate.
For this training class, the following settings must be configured as shown.
Save your changes in the suggested directory and click Done to exit.
Note: Click Save to save the current settings entered for the selected communication port. The Communication Port Settings dialog box remains displayed and another communication port can be configured.
Creating Topic Definitions
The Configure / Topic Definition command is used to create, modify, or delete topic definitions.
One or more topic definitions must exist for each PLC that the I/O Server will communicate with.
Each topic definition must contain a unique name for the PLC associated with it. This unique name is then used as the topic name portion of the DDE Address for all DDE conversations to that PLC.
Click Configure / Topic Definition.
The Topic Definition dialog box appears:
Note: Once topics have been defined, their names will be listed in the Topics pane of this dialog box.
Click New to add a new topic definition.
The MODBUS Topic Definition dialog box appears:
Topic Name: Enter a unique name (up to 32- characters long) for the PLC in the field.
Note: When communicating with InTouch, this exact name is used as the topic name in the Access Name definition.
ComPort: Select the communications port to be associated with this topic.
Slave ID: Enter the Slave ID of the PLC in the box.
Slave Device Type: Drop-down list contains slave device types other than the default. String Variable Style: The PLC will use this style to store ASCII strings in its registers. Register Type: Select BINARY or BCD, based on hardware used.
Block I/O Sizes: Coil Read: Enter the maximum number of consecutive coils to be read at one time. In this example, the valid coil read values can be between 8 and 2000 and must be an even multiple of 8.
Coil Write: Enter the maximum number of consecutive coils that can be written to at one time. In this example, the valid coil write values can be between 8 and 800 and must be an even multiple of 8.
Register Read: Enter the maximum number of consecutive registers to be read at one time. In this example, the valid register read values can be between 1 and 125.
Register Write: Enter the maximum number of consecutive registers that can be written to at one time. In this example, the valid register write values can be between 1 and 100. Update Interval: Enter the frequency (in milliseconds) that the I/O Server will read (poll) the items/points associated with this topic. Different items/points can be polled at different rates by defining multiple topic names for the same PLC and setting different update rates for each topic.
Click OK to accept the entries and close the dialog box.
The Topic Definition dialog box will open with the new topic listed:
Click the Done button to close this dialog box and return to the server’s program window. Click Modify to change an existing topic definition.
Click Delete to delete an existing topic definition.
Note: The previous information is provided for example only. Configuration steps for this class are provided in the following lab.
Troubleshooting I/O
Explain troubleshooting InTouch I/O
This section explains how to troubleshoot I/O communication between the I/O Server and InTouch and between the I/O Server and the PLC.
Note: All I/O Server setup which follows is specific to the Wonderware facility training environment. Your instructor will provide the proper configuration information.
The following figure illustrates where the failures can occur:
Communication Between InTouch and the I/O Server
Error situations can occur when attempting to establish an I/O conversation between InTouch and an internal I/O Server.
When WindowViewer requires the status of a I/O item, it opens a channel with the I/O Server and requests it to advise WindowViewer when the DDE item changes.
The I/O Server automatically handles all of the messages to and from the PLC. The client application simply tells the I/O Server what register, coil number or I/O point to read or write. The I/ O Server then automatically updates the client upon any change of that data value.
It is highly recommended that you always start the I/O Server before starting WindowViewer. If WindowViewer attempts to establish a channel with an I/O Server that is not running, the Initializing I/O message box will open for each un-initialized I/O conversation.
When this dialog box appears, note the information on the second line. This information indicates that at least one tag in WindowMaker is linked to an Access Name that defines MODBUS as the application name and PLC1 as the topic name.
In this case, when the WindowViewer program was started, it immediately looked for an I/O Server application named MODBUS containing a topic defined as PLC1. It could not find this application and/or topic and is notifying you that communications cannot be established.
The following describes the three situations that will cause the previous dialog box to open. The I/O Server is not running.
The I/O Server application (MODBUS in this case) is not running. You can verify this by opening the Windows Task List (CTRL+ALT) and checking the list of currently running applications for the MODBUS server. The server’s program name is misspelled in the Access Name definition.
The server is running, but its name is misspelled in one or more Access Name definitions. The name entered in the Access Name definition must be the I/O Server’s actualprogram name (less the .EXE extension) as seen in the Windows Explorer. The topic is not defined in the server or it is misspelled.
Assume that the server’s name is spelled correctly and is running. WindowViewer is now looking for a topic defined in the server as PLC1. To check the topic name, close WindowViewer. The server cannot be configured if WindowViewer is running. Open the I/O Server’s program window and click Configure / TopicDefinition. If there is a topic defined as PLC1 listed in the dialog box, ensure that it is spelled exactly the same (including spaces, and so on) as it is in the Access Name definition field.
Note: Be sure there are no blank spaces after the topic name in both the server and in the Access Name definition in WindowMaker.
When you have confirmed all of the above situations, restart WindowViewer and switch to the server’s program window. Data should now appear in the window. This data indicates that WindowViewer and the server are communicating. The data also indicates read and write messages that the server is attempting to send to the PLC. These are not error messages: only status messages are written to this window.
If no data appears in the server’s window, check the Error Log in FactorySuite for error messages.
The most common error message is:
Error for DDE: MODBUS|PLC1!<null> (“item”) Advise failed
This error message indicates that the item used on one or more tagnames is unrecognized by the server. InTouch tagnames use specific naming conventions when accessing data from a server.
Monitoring Communication Status Between InTouch and the I/O Server
WindowViewer supports a built-in topic name called IOStatus that can be used to monitor the status of specific I/O conversations. When monitoring an I/O conversation using IOStatus, you must define at least one I/O-type tag for the Access Name being monitored.
Assume that WindowViewer (View) is communicating with the Wonderware Modbus I/O Server to a PLC that has been defined in the I/O Server with PLC1 for its topic name.
Note: Every Topic in Wonderware I/O Servers includes a Status bit.
Click Special / Tagname Dictionary to open the Tagname Dictionary dialog box.
Create an I/O Discrete type tag.
Click Access Name to assign the tag to an Access Name definition that defines IOStatus for its topic name.
The Access Name Definition dialog box appears.
Notice that an Access Name definition called PLC1 (the topic we need to monitor) currently exists. To be sure that this is the correct Access Name (with Topic Name of PLC1), you will need to access the Modify Access Name window.
Select PLC1 and click Modify.
Finding the Access Name containing the right topic name in this example is easy because we kept the tagname and the Topic Name the same.
Click Cancel to close the dialog box and return to the initial Access Name Definition dialog box.
The Access Name dialog box appears.
Click Add.
The Add Access Name dialog box appears:
In the Access field, enter IOStatus.
Since you are going to monitor the status in WindowViewer, in the Application Name field, enter View.
In the Topic Name field, enter the InTouch internal topic, IOStatus.
Select Advise only active items.
Click OK to close the dialog box.
The initial Access Name Definition dialog box reappears displaying the new Access Name, IOStatus:
Click Close.
In the Item box, enter the actual Access Name to monitor, in this case, PLC1.
When configuring a monitor text link, point the links to their respective I/O Tags and configure Text Color- and/or Value Display- DISCRETE animation links to the tags.
Testing for the ServerStatus link can be done by shutting down the I/O Server (in this example, MODBUS).
Restart the I/O by restarting the MODBUS server, then select Special/Reinitialize I/O in the WindowViewer main menu.
Monitoring Communication Status Between the I/O Server and the I/O Device
For each topic name being used, there is a built-in discrete item, Status, which can be used to monitor the state of communications with the I/O Servers program.
Status is set to 0 when communication with the device fails (cable disconnected, PLC is powered down, and so on) and is set to 1 when communication is successful.
Note: When monitoring the status of a topic using the Status item, at least one I/O point must be active.
From InTouch, read the status of server communication by defining a tagname and associating it with the topic configured for the device.
Status must be used as the item name.
For example, if WindowViewer is communicating with a PLC using the Wonderware Modbus I/O Server, the Access Name definition would be as follows.
To monitor the status of all communication to the topic, PLC1, create the following tagname definition.
Testing for the PLC1 topic (previous example) can be done by disconnecting the PLC.
Monitoring I/O communication status from Excel
From Excel read the status of PLC communication by entering the following formula in a cell:
=MODBUS|PLC1!’STATUS‘
Using IOStatus Topic Name in Excel
Excel can also be used to perform this same type of monitoring by entering the same information in a formula in a spreadsheet cell. For example, to monitor the same topic as above, the following would be entered:
=view|IOStatus!’PLC1′
Configuring I/O Communication Wonderware intouch
In this post, you will configure a Modbus server and establish communication with I/O-aware programs by creating and animating new tags.
This lab was developed using a Koyo PLC as the data source. If a PLC containing simulation logic is not available, a similar lab using the SIMULATION program is provided in Appendix F, “I/O Simulation.” The SIMULATION program is included with InTouch.
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Configuring the Modbus I/O Server is included as an instructor-led task starting on page 8-13. If the I/O Server has not yet been configured, please do so at this time.
Note: All I/O Server setup which follows is specific to the Wonderware facility training environment. Your instructor will provide the proper configuration information.
Upon completion of this post, you should be able to:
Start and Configure the Modbus Server
Define the MODBUS Topic
Create a New Access Name
Create a New Factory Floor Window
Start and Configure the Modbus Server
If not already started, start the Modbus server by clicking
Start / Programs / Wonderware FactorySuite / IO Servers / Modicon MODBUS.
When the server is running, click Configure/Com Port Settings. Ensure the following settings are configured.
Click Done.
Define the MODBUS Topic
Click Configure / Topic Definition.
Click New.
The Modbus Topic Definition window appears:
Enter PLC1 in the Topic Name field.
Ensure COM1 is selected in the Com Port field.
Select BCD as the Register Type. Enter 100 for the Update Interval.
Click OK.
The Topic appears in the Topic definition dialog Topics pane:
Click Done.
Minimize the Modbus server.
Maximize WindowMaker.
Create a New Access Name Select Configure / Access Names from the WindowMaker Application Explorer.
Double-click Access Names.
Click Add.
The Add Access Name dialog box displays.
Enter the information shown in the following figure.
Click OK to accept the new Access Name.
Your new Access Name is now displayed in the Access Names pane.
Click Close.
Create a New Factory Floor Window
In this lab, we will create a new window called Main, where materials will be received from the hopper into a mixing drum. There will be two valves attached to the mixing drum allowing two more materials to be added. The mixture will then be agitated and drained. For a complete description, please see page page 8-24.
Create a new window called Main.
Important: All tags except the Start tag should be configured as ‘read-only’.
Create the following tags. Since we will be communicating with the PLC, the tags will need to be assigned to the Access Name, PLC1 with the Items listed below.
| Tagname | Tag Type | Access Name | Item |
|---|---|---|---|
| Start | I/O Discrete | PLC1 | 2049 |
| Gate_Valve | I/O Discrete | PLC1 | 2050 |
| Valve_A | I/O Discrete | PLC1 | 2051 |
| Valve_B | I/O Discrete | PLC1 | 2052 |
| Agitator | I/O Discrete | PLC1 | 2053 |
| Drain_Valve | I/O Discrete | PLC1 | 2054 |
| Tank_Level | I/O Integer | PLC1 | 40001 |
(Min/Max EU 0-1000)
(Min/Max Raw 0-1000)
Add text for each of the tags in the Main window.
Link each text object to the appropriate tag as follows.
Tagname Animation Link
Start Touch Pushbutton – Discrete Value – Toggle, Discrete Text Color – Green/Red
Gate_Valve Discrete Text Color – Green/Red
Valve_A Discrete Text Color – Green/Red
Valve_B Discrete Text Color – Green/Red
Agitator Discrete Text Color – Green/Red
Drain_Valve Discrete Text Color – Green/Red
Tank_Level Value Display – Analog
Switch to Runtime to test the links.
The Start text field should toggle between Green and Red when clicked.
The Gate_Valve text field should change from Green to Red when the tag value changes.
The Valve_A and Valve_B text fields should change from Green to Red when the tag value changes.
The Agitator text field should change from Green to Red when the tag value changes.
The Drain_Valve text field should change from Green to Red when the tag value changes.
The Tank_Level text field should change when the tag value changes.
Now, you are on your own . Try to be as creative as you can. For example; use as many animation links as possible, implement trending, try using wizards, bitmaps, and so on.
The materials you use in this process visualization are completely up to you.
Important Note: Process Description:
When ‘Start’ is set to True, the ‘ increase until it reaches 300, at
Gate_ Valve ’ will open and the ‘Tank_Level’ will start to which point Gate_Valve will close.
‘Valve_A’ will then open and the ‘Agitator’ will turn on to mix the product. When the ‘Tank_Level’ reaches 600, ‘Valve_A’ will close and ‘Valve_B’ will open.
When the ‘Tank_Level’ reaches 1000, ‘Valve_B’ will close, the ‘Agitator’ will turn off, and the ‘Drain_Valve’ will open, causing the ‘Tank_Level’ to decrease to 0 (zero).
This process will repeat as long as the ‘Start’ point remains True. If ‘Start’ is set to ‘False’, the process will stop when the ‘Tank_Level’ value reaches 0 (zero).
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