OPC-UA and Device Connections

Connecting to a OPC Server

OPC-UA Server

An OPC-UA Connection is used to communicate with an OPC-UA compliant server, such as the one the OPC-UA module provides.

The following steps walk-through connecting Ignition (as an OPC-UA client) to a OPC-UA server:

OPC-UA Server properties

Failover Versus Backup Properties 

The Failover properties should be used when a single Ignition gateway needs to connect to a pair of redundant OPC-UA servers. The failover OPC-UA server will be used in the event the primary OPC server goes down.  To enable failover, set the Failover Enabled property to true, and specify the Failover Endpoint. The Failover Threshold can be adjusted if desired. 

The Backup properties should be used when a pair of redundant Ignition gateways are trying to look at the same OPC-server. Both the Backup Discovery URL and Backup Endpoint URL properties need to be configured. 

Connecting to OPC Classic (COM)

The OPC-COM module provides the ability to connect to OPC servers that only communicate using the older COM based OPC-DA standard. If you have an OPC server that is not capable of accepting OPC-UA connections and you need to talk to a PLC for which Ignition has no supported driver, you'll have to use the OPC-COM module to make your device data available in Ignition. Connections to OPC servers will be held open while the Ignition Gateway is running. All subscriptions to the server will use the same connection.

This section provides a brief walk-through of how to set-up a new Local or Remote OPC-DA server connection using the COM module. Due to the complications that Windows DCOM security settings can cause, this set-up guide is followed by the Troubleshooting OPC-COM Connections section that deals with an overview of how to deal with a faulted server connection due to DCOM security settings as well as other possibilities.

To Install OPC Core Components

1. Register at www.opcfoundation.org . 
   The OPC-COM module relies on a .dll package provided by the OPC Foundation ( www.opcfoundation.org ) called the OPC Core Components. You can download the OPC Core Components Redistributable from the OPC Foundation's website under the downloads section. Registration with the OPC Foundation is required before you can download the package, but the registration process is free and painless.
    
2. Download appropriate OPC Core Components Redistributable package.  
   There are two packages to choose from, the 32-bit (x86) and the 64-bit (x64), make sure you get the correct one for the version of Java and Ignition you are running. 64-bit Java and Ignition needs the 64-bit Core Components package and likewise 32-bit installations needs the 32-bit package. 
   
   
3. Install Core Components on Ignition server.
   It should be noted that if you are going to connect to an OPC server on a remote machine, you must also install the appropriate version of the Core Components on that server as well. The version type, 64-bit or 32-bit, does not need to be the same across the two servers. Just be sure to install the version that is appropriate for the OPC Server and Windows architecture.
    
4. (Remote) Install Core Components on remote machine running the OPC-DA server.
   Once you have the correct package downloaded you can extract the contents of the .zip file and then run the installer. With the core components installed you can now proceed to setting up your OPC-DA server connection in Ignition.

Connecting to OPC-DA Server

With the OPC Core Components now installed the next step is creating/configuring a new OPC-DA server connection.

To Install OPC-DA server connection

1. Go to the Ignition Gateway Configure section ( http://localhost:8088/main/web/config).
2. Go to OPC Connections > Servers and then select Create new OPC Server Connection....
    
3. Choose the OPC-DA COM Connection and then s elect whether you want to make a Local  connection or if the OPC server resides on a Remote machine. For the most part, setting up a local or remote connection to an OPC-DA server is the same. There are only a couple of differences for a remote connection that will be highlighted along the way.
   Local - Selecting a local connection takes you to a screen that contains a list of the available and running OPC servers located on the local machine.
   Remote - For a remote connection you first have to specify the host name or IP address of the machine the the OPC server resides on and then (as of Ignition 7.4) you are redirected to the available servers list.
    
4. Select the OPC server that you wish to connect to from the list. In the case where your server is not listed, see the OPC server is not listed... the  Troubleshooting OPC-COM Connection  section.
   
   Unique Remote Connection Settings
   Remote connections have a few unique settings that you can specify. You can get to these settings by selecting the Show advanced properties check box. As of Ignition 7.4 these should all be set for you (except for the CLSID which should no longer be necessary but is still available for you to set if you wish).
   
   Remote Server
   Specifies that the server is remote and that a DCOM connection will be used.
   
   Host Machine
   The computer name or IP address of the machine on which the remote server is running.
   
   CLSID
   This is no longer required as of Ignition 7.4, but it is still made available for you. It can be used in place of the ProgId because the ProgId is really just used to lookup the CLSID in the registry. This id can be found in the registry of the machine hosting the server under:
   HKEY_CLASSES_ROOT\OPCServerName\CLSID
    
5. All of the settings for the server connection are rather straight forward and each property has a description of its functionality. Most of these settings should be fine when left at their default values. The only setting that could possibly give you some trouble is the ProgId. If you selected your OPC server from the list on the Choose OPC-DA Server page, this will be filled in for you. However, if for whatever reason your server wasn't listed and you choose the Other Server option, you will have to know the ProgId for your server and specify it here. The ProgId is used to look up the CLSID of the OPC Server in the Windows Registry and without this a connection cannot be made.
    
6. When you are finished fine tuning these settings click Create New OPC Server Connection. You will be redirected to the OPC Server Connections page and your new server connection should be listed. The status of your connection will read Connected if Ignition was able to successfully connect to the third-party OPC server.

Connection is Faulted

In the case where your connection status is reporting Faulted, the troubleshooting process begins. As previously stated, configuring the DCOM settings on your machine can be a headache. The  Troubleshooting OPC-COM Connections section next is an attempt to ease the process of determining why your connection is faulted and how to go about fixing the issue. If after exhausting the options presented to you, you are still having issues getting you server connection up, give our Inductive Automation tech support line a call and one of our representatives will be happy to assist you.

Troubleshooting OPC-COM Connections

This section provides you with a list of common OPC-COM connection problems with their possible solutions. It would be impossible to give an exhaustive list of everything that can go wrong but this should give you a good start on the troubleshooting process. If you do not see your problem listed and your connection status is faulted, try following the steps outlined in the Ignition Server DCOM Settings and OPC Server DCOM Settings sections.

Common Problems

OPC server is not listed in Choose OPC-DA Server list when first creating a connection

There are some cases in which an OPC Server that is installed will not show up in the generated list. This list is generated by the OPC Server Enumerator which is part of the OPC Core Components, so when a server you have installed on the machine does not appear in this list it is likely due to the OPC Core Components not being installed correctly.

Try reinstalling the Core Components and going through the process of creating a new server connection in Ignition again. If the server still does not appear and you have the ProgId (or the CLSID for a remote connection) for the OPC server, you can just select the Other Server option and then click Next. In this situation you will have to enter the ProgId manually on the New OPC-DA Server page.

With all the correct information about the OPC server we can sometimes still make a valid connection to the OPC Server even when it is not detected automatically. This however is rare. Most of the time when the server is not detected, any connection attempts Ignition makes will fail.

Connection status is Connected but data quality is bad or the connection goes Faulted after trying to read tag data

Usually this occurs when the DCOM settings for the machine on which Ignition is running are not correctly configured. DCOM connections go in both directions. Ignition must be able to send requests to the OPC server and the OPC server must also be able to callback to Ignition. If the DCOM settings on the Ignition server are not configured correctly those callbacks will fail and the server connection that initially had a status of “Connected” will either fault or all the tags that you have configured will come back with bad quality.

This is a problem that can affect both local and remote server connections.

Follow the steps outlined in the “Ignition Server DCOM Settings” section to ensure that you have correctly configured the DCOM security settings on the Ignition server machine.

Ignition launches second instance of an already running OPC server and is unable to see any data

It is important to note that Ignition runs as a service under the Windows System account. This can cause some issues with OPC servers that are meant to run interactively, meaning they run under the user account that is currently logged on. When Ignition attempts to make a connection to the OPC server, it will attempt to find an instance running under the same account and if it doesn't find one it will launch its own instance under the System account. Even if there are other instances running, Ignition will choose the one that was launched under the System account for its connection.

Many OPC servers maintain an instance running under the interactive user account that has been configured by the user and maintains all of the device connection information. When Ignition launches a new instance, this configuration information is lacking and none of the desired data can be seen or accessed. To get around this problem, you must specify in the DCOM settings for the OPC server that it always identify itself with the interactive user. Essentially this will force Ignition to use the currently running instance of the OPC server.

To set the OPC server to run as Interactive User

1. The DCOM settings are found in the Component Services manager. Right-click the entry for your OPC server under the DCOM Config folder and select properties from the popup menu.
2. Select the Identity tab, select the option that reads The interactive user, and click OK.
3. Close out of component services and kill any extra instances of the OPC server you see running in the Task Manager.
4. Go edit and save the OPC server connection in the Ignition Gateway.

Faulted status with E_CLASSNOTREG error reported on OPC connections status page

This is almost always caused by the OPC Core Components not being installed correctly. Download and install the correct version(s) for your system(s) from the OPC Foundation (www.opcfoundation.org). Remember, if you are making a remote connection you must install these components on both the Ignition server as well as the machine on which the OPC server is running.

DCOM Settings

Ignition Server DCOM Settings

Follow these steps to open up the DCOM security settings on the machine that is running Ignition:

1. Open the Windows Component Services, located in the Administrative Tools section of the Control Panel.
    
2. Browse down through the Component Services tree until you see My Computer, right-click and select Properties.
    
3. We want to focus on the COM Security tab. There are two sections, Access Permissions and Launch and Activation Permissions. Each section has an Edit Limits... and  Edit  Defaults... button. You must add the ANONYMOUS and Everyone accounts under each of the four areas making sure that the Allow option is checked for each of the permission settings. If you skip adding both of these to either the limits or defaults areas under either of the two sections there is a good chance your connection will not be successful.
    
4. You can also try setting the Default Authentication Level to None and the Default Impersonation Level to Identify on the Default Properties tab. This isn't always necessary but it can sometimes help.

OPC Server DCOM Settings

Follow these steps to open up the DCOM security settings on the machine that is running the OPC server:

1. Open up Windows Component Services, located in the Administrative Tools section of the Control Panel.
2. Browse down through the Component Services tree until get to the DCOM Config folder.
3. Locate the entry for your OPC server that you wish to make a connection to, right-click and select properties.
4. Click the Security tab and you will see three sections, Launch and Activation Permissions, Access Permissions, and Configuration Permissions. There are two options to choose from for each section. If you already added the ANONYMOUS and Everyone accounts to the COM Security section from the Ignition Server DCOM Settings section then you can go ahead and just select the Use Default option for each of the three areas. The second option is to edit each of the groups that have Customize selected. You will have to add both the ANONYMOUS and Everyone accounts with all privileges.
5. Now select the Identity tab. You will notice that you can choose which account you want to run the OPC server under. Select the Interactive User option. This ensures that if Ignition launches an instance of the OPC server, it will run under whichever user is currently logged into the system.

Creating an OPC-HDA Connection

The process of connecting to an OPC-HDA server is similar to that of a DA server. Instead of going to the "OPC Connections" section, however, you define the server as a Tag History Provider.

1. Navigate to the Ignition gateway configuration section, as outlined above.
2. Under Tags, History, select "Create new Historical Tag Provider..."
3. Select "OPC-HDA Provider"
4. Follow the step outlined above, for DA connections.
5. Once complete, the status on the Tags>History screen will show the state of the connection. If Connected, you should now be able to browse and query the server through the Ignition designer.

Example - Adding OPC-HDA data to a chart

1. Open the designer, and create or open a project.
2. Create a window, and add an Easy Chart component.
3. Double-click on the chart, or right click and select Customizers>Easy Chart Customizer to bring up the chart customization window.
4. Next to the "Tag History Pens" table, select the first button, "Browse for tags". This will display a tree for browsing all historical tags.
5. Browse through your defined HDA server. Once you find a tag, select "ok" to add it to the chart.
6. You may edit the tag to alter its aggregation mode, though the HDA provider will select a supported mode automatically if the specified mode does not exist in the server.
7. Once you save the configuration, the chart should update with the requested data.

A similar procedure can be used anywhere Tag History can be bound or used.

OPC Quick Client

You can access the OPC Quick Client from under the OPC Connections section of the Ignition Gateway Config section. It allows for quick, simple testing of any devices connected to the server. 

You can browse by expanding tree nodes and read/write to tags by clicking on the [r] and [w] buttons next to those tags.

Subscriptions can be made by clicking on the [s] button. Clicking on the enable live values link will automatically refresh subscriptions and show live value changes (if there are any).

Ignition OPC-UA Server

You can see the following OPC-UA Server Settings by going to the Configure section of the Gateway and then choosing OPC-UA > Settings.

Creating a New Device

To add a new Device go to the Devices section of the OPC-UA module configuration in the Ignition Gateway, go to the Configure section of the Gateway and then to OPC-UA > Devices. Once at the Devices page, click on the Create new Device... link at the bottom of the table. You will be taken to a page where you can select the driver to use. Choose your driver and click Next.

The General settings common to all devices are as follows:

Verifying Device Connectivity

Device connectivity can be verified in the following three places:

• In the Status page of the Gateway under OPC-UA Server > Devices
• In the Status page of the Gateway under Overview > Device Connections box
• In the Status page of the Gateway under Overview >  OPC Connections box

Drivers

Allen Bradley Drivers

ControlLogix 5500

You will see the following Connectivity settings on the New Device page accessed from the Configure section of the Gateway under OPC-UA > Devices.

MicroLogix 1100/1400

Supported MicroLogix Connection Methods

MicroLogix 1100 and 1400 direct
MicroLogix 1100 and 1400 connected through 1761-NET-ENI
MicroLogix 1100/1400 connected through Spectrum Controls WebPort 500

Note: MicroLogix 1200 and 1500 are not fully supported. Browsing is not available on these devices.

PLC-5

More Information On Connection Path

The Connection Path format contains 4 numbers separated by commas. The first number is always 1 and tells the 1756-ENET module to route through the backplane. The second number is the slot number of the 1756-DHRIO module of the DH+ network the PLC-5 processor is connected to. The third number is the channel of the 1756-DHRIO module that the PLC-5 processor is connected to. Use 2 for channel A and 3 for channel B. The final and fourth number is the DH+ node number. This number is in octal and is the same as configured in the PLC-5 processor. See the ControlLogix Ethernet Communication interface Module User Manual for more information.

Connection Path Format: 1,<1756-DHRIO slot number>,<1756-DHRIO channel>,<DH+ node number>

The valid range for the 1756-DHRIO slot number is between 0 and 16 but depends on the chassis size. The 1756-DHRIO channel is either 2 for channel A or 3 for channel B. The DH+ node number range is from 00 to 77 octal.

For a more in depth explanation of connection paths please read: Allen Bradley Connection Paths Explained.

Supported PLC-5 Connection Methods

PLC-5 L/20E, L/40E, L/80E direct
All PLC-5 processors connected through DH+ via the 1756-DHRIO module.

SLC 505

More Information On Connection Path

The Connection Path format contains 4 numbers separated by commas. The first number is always 1 and tells the 1756-ENET module to route through the backplane. The second number is the slot number of the 1756-DHRIO module of the DH+ network the SLC processor is connected to. The third number is the channel of the 1756-DHRIO module that the SLC processor is connected to. Use 2 for channel A and 3 for channel B. The final and fourth number is the DH+ node number. This number is in octal and is the same as configured in the SLC processor. See the ControlLogix Ethernet Communication interface Module User Manual for more information. 

Connection Path Format: 1,<1756-DHRIO slot number>,<1756-DHRIO channel>,<DH+ node number>

The valid range for the 1756-DHRIO slot number is between 0 and 16 but depends on the chassis size. The 1756-DHRIO channel is either 2 for channel A or 3 for channel B. The DH+ node number range is from 00 to 77 octal.

For a more in depth explanation of connection paths please read: Allen Bradley Connection Paths Explained.

 Supported SLC Connection Methods

SLC505 direct
SLC505, SLC504, SLC503 connected through 1761-NET-ENI
SLC504 connected through 1756-DHRIO
SLC505, SLC504, SLC503 connected through Spectrum Controls WebPort 500

Allen Bradley Connection Paths Explained

Connections to ControlLogix, CompactLogix, PLC-5, MicroLogix and SLC Allen-Bradley processors through a ControlLogix Gateway require a connection path. The connection path is unique to your setup and is dependent on what modules the connection is being routed through. With there being nearly an endless number of ways to route your connection from device to device it is impossible to give an example of every possible connection path, but in general there is a pattern to how the connection path is specified.

Follow the Path

A connection path is exactly what it sounds like. It is a path that when followed will lead a processor residing in a numbered slot of a chassis somewhere on site. You merely have to follow the path and build the connection path as you go. The first connection point between Ignition and the device is a ControlLogix Ethernet module such as an ENET, ENBT or EN2T module. The slot number of this module doesn't matter and there is no need to specify it in the connection path. The first entry in any connection path will be a 1, which specifies moving to the back plane. You then specify the slot of the module you wish to move to, followed by the port or channel of that module that you wish to exit through. Finally you specify the address of your entry point to the next module and the process starts all over again. This process may sound complicated at first but after some practice it will get easier.

Steps

1. Move to the backplane.
2. Specify the slot number of the module you are moving to.
3. Specify the exit port or channel.
4. Specify address of entry point (DH+ Station Number / ControlNet Address / IP Address of ethernet module).
5. Move to the backplane.
6. Specify processor slot number OR the slot number of the module you wish to exit through.

Connection Path Entries for Different Module Types

How you specify your exit point from a module is slightly different depending on which module type you are using. You can only move in two directions once you are "in" a module: out to the back plane, or out through the module port/channel. Ethernet modules have ethernet ports and an IP address; ControlNet modules have ControlNet Ports and ControlNet addresses; DHRIO modules have channels and station numbers. Below is a list of different kinds of modules and what numbers you specify in the connection path when you are exiting or entering those modules. When in a module, an entry of 1 will always take you to the backplane.

ENET, ENBT, and EN2T:
Exiting
1 = Backplane
2 = Ethernet Port
Entering
IP Address

CNB:
Exiting
1 = Backplane
2 = ControlNet Port
Entering
ControlNet Address

DHRIO
Exiting
1 = Backplane
2 = DH+ Channel A
3 = DH+ Channel B
Entering
DH+ Station Number (an octal value between 0-77)

You use these numbers to specify how to move out of the module, then you specify where you are moving to by either specifying the DH+ station number, ControlNet address, or the IP address of another ethernet module. Your connection path will always be an even number of entries due to the fact that you always move in two steps: out of a module and then in to another module. So if your connection path ends up with an odd number of entries you have missed a step somewhere and you'll have to go back and trace the path again.

Some examples have been included to help illustrate the process of tracing a connection path. The first three examples illustrate how to build your connection path when going from one ControlLogix Gateway to another. The last example shows connecting through a ControlLogix Gateway to 3 different SLC 5/04 devices via DH+.

Creating an OPC-HDA Connection

The process of connecting to an OPC-HDA server is similar to that of a DA server. Instead of going to the "OPC Connections" section, however, you define the server as a Tag History Provider.

Example - Adding OPC-HDA data to a chart

A similar procedure can be used anywhere Tag History can be bound or used.

A Frequently Asked Question

How to I get data from my PLC?

Getting data from your PLC into Ignition is a two step process:

1. Add a device, see Connecting to a Device.
2. Add some tags, see Creating Tags.

It requires you to touch both the Ignition Gateway and the Ignition Designer. There are also some limitations as to what kind of devices you can connect to Ignition and these are explained throughout the user manual, however included below is an overview of what you can expect when it comes to compatibility.

Brief summary of device connection in Ignition

• Ignition can only connect directly to devices over Ethernet. 
• Ignition can only connect directly to devices for which there is an Ignition device driver. Included drivers are:
  • Allen Bradley - ControlLogix 5500, CompactLogix, MicroLogix 11/1400, PLC-5, SLC 505
  • Siemens - S7-300, S7-400, S7-1200
  • Modbus - The Modbus driver connects to any ethernet enabled device that uses the Modbus protoco
• Ignition can connect to third party OPC servers via OPC-UA or OPC-DA (using the OPC-COM module) for devices that do not have a supported driver.

Adding a Device to Ignition

Ignition Supported OPC-UA Device

Most commonly you will be adding a device that is supported by one of the built-in device drivers. The first step is connecting your device to Ignition. This is done through the Ignition Gateway Configuration section under the OPC-UA -> Devices page.

1. Click "Add a device..."
2. Select the driver for the device you wish to add
3. When adding a device you will notice that there are some common settings that are shared by all devices. You can find an explanation of these settings here: Adding a New Device
4. Specify any of the required device specific settings for the device (For example, hostname, etc.)
5. Check the status of your device to see if it is connected.

As long as all the device information you entered was correct you should see your device in a "Connected" state. The only exception to this is if you chose to add a Siemens or Modbus device. Since these devices don't support the browsing of tags you will have to create and address some tags in the Ignition designer before the device will stop cycling from a connected to disconnected state.

If you need to address your tags for your Siemens or Modbus device you'll want to read about adding Tags in the Ignition Designer as well as how addressing works for the different protocols. You will have to first add a tag in the Ignition designer and then edit the OPC Item Path of the tag using the appropriate addressing scheme.

Adding Connection to 3rd Party OPC Server via OPC-UA

If your device does not have an Ignition driver, you can use a 3rd party OPC server to connect to your device and then have Ignition connect to the server as a client. If the OPC server talks OPC-UA, you can add a new OPC-UA server connection in the Ignition Gateway. Configuration will be different depending on what OPC server you are using but the following is an example of a popular solution, connecting to KEPServer via OPC-UA, see Connecting to Kepware OPC-UA.

Adding Connection to 3rd Party OPC-Server via OPC-COM

The following section provides a detailed walk-through on how to connect to an OPC server using the OPC-COM module. If Ignition doesn't have a driver for your device and you don't have an OPC server that talks OPC-UA, you have to connect using the OPC-COM module, see   Connecting to OPC Classic (COM) .

Adding tags for Allen Bradley devices

Tags are how Ignition represents your PLC tags. You create Tags in the Ignition Designer and then you can use these tags to store history or display PLC data in your projects.
For the most part, Allen Bradley devices support browsing of tags in the PLC. There are a few exceptions like the MicroLogix 1200/1500 for which you have to manually address your tags. For now we will focus on creating tags from devices that support browsing.

1. Open the Ignition Designer.
2. Drag desired tags from the OPC Browser to the Tag Browser as described here: Creating Tags (if you don't know what Tag Provider means don't worry, merely drag them into the Tags folder). You should now see some tags in the Tag Browser that show the current values of the respective tags in your PLC. Don't stop here. You should read through the related links below so you can learn more about Tags and how they work.

Simulator Drivers

Generic Simulator

The generic simulator provides a variety of tags that offer different data types and value generation styles. For example, there are ramps, sine waves, and random values. Additionally, there is a set of static writable tags whose values will persist while the device is running.

There are no configurable settings for the generic simulator.

Simulator tags

ReadOnly - static values that do not change for read only purpose.

ReadOnlyBoolean1 - false
ReadOnlyBoolean2 - true
ReadOnlyShort1 - 1
ReadOnlyShort2 - 2
ReadOnlyInteger1 - 1
ReadOnlyInteger2 - 2
ReadOnlyLong1 - 1
ReadOnlyLong2 - 2
ReadOnlyFloat1 - 1.1
ReadOnlyFloat2 - 1.2
ReadOnlyDouble1 - 1.1
ReadOnlyDouble2 - 1.2
ReadOnlyString1 - "ABCDEFG"
ReadOnlyString2 - "ZYXWVUT"

Writeable - static values that you can read/write to, initial values below.

WriteableBoolean1 - false
WriteableBoolean2 - false
WriteableShort1 - 0
WriteableShort2 - 0
WriteableInteger1 - 0
WriteableInteger2 - 0
WriteableLong1 - 0
WriteableLong2 - 0
WriteableFloat1 - 0
WriteableFloat2 - 0
WriteableDouble1 - 0
WriteableDouble2 - 0
WriteableString1 - "" (empty string)
WriteableString2 - "" (empty string)

Random - Random values updating at some rate, they follow Java Random(rate) - rate is the seed.

RandomBoolean1 - 10 sec
RandomShort1 - 5 sec
RandomInteger1 - 1 sec
RandomLong1 - 2 sec
RandomFloat1 - 10 sec
RandomDouble1 - 10 sec

Sine - Different sine waves with frequency, amplitude and offset (listed in that order)

Sine1 - 0.1, 100.0, 0.0
Sine2 - 0.01, 50.0, -25.0
Sine3 - 0.02, 10.0, 10.0
Sine4 - 0.04, 100.0, 0.0
Sine5 - 0.08, 100.0, 0.0

Ramp - Ramp signals starting from 0 going up to some value at the specified rate. When they reach their upper limit, they are reset to zero.

Ramp1 - 0 - 100 @ 10 ms
Ramp2 - 25 - 75 @ 100 ms
Ramp3 - 0 - 100 @ 50 ms
Ramp4 - 0 - 100 @ 25 ms
Ramp5 - 0 - 100 @ 12.5 ms

Realistic - Values determined by adding a random number (between -1 and 1) to the current value.

Realistic1 - -50 - 50 @ 500 ms
Realistic2 - -50 - 50 @ 1000 ms
Realistic3 - -50 - 50 @ 1500 ms
Realistic4 - -50 - 50 @ 2000 ms
Realistic5 - -50 - 50 @ 2500 ms

Allen Bradley SLC Simulator

The SLC simulator driver creates a simple device whose address structure mimics a basic SLC structure. There are currently no configurable parameters.