What is FactoryTalk Logix Echo?

FactoryTalk Logix Echo is Rockwell Automation’s next generation of Logix 5000 controller emulator.

In this post, I’ll walk you through the key features of FactoryTalk Logix Echo and explain how FactoryTalk Logix Echo is positioned against Rockwell Automation’s current controller emulator, Studio 5000 Logix Emulate.

Let’s start by looking at some of the key features of FactoryTalk Logix Echo.

Features

ControlLogix 5580 Emulation

FactoryTalk Logix Echo is the only tool available to emulate ControlLogix 5580 PLCs. These are the latest generation of ControlLogix PLCs that are used for large projects.

With FactoryTalk Logix Echo, you can test the software for these large projects before the physical hardware is available to de-risk projects.

The best part is that you don’t have to modify a project to download it to FactoryTalk Logix Echo - you can download the project directly to an emulated controller without modifications and the emulated chassis supports up to 17 controllers. Within Logix Echo, the I/O tree is maintained and the emulated controller supports all of the programming languages and instructions that are supported by a physical controller.

Update: As of Logix Echo version 2, you can also emulate GuardLogix 5580 controllers. Check out all the new features of Logix Echo version 2 here.

Ethernet Port Emulation

FactoryTalk Logix Emulate also emulates the front port of a Logix 5580 controller.

This means that you can exchange data between emulated controllers using produced and consumed tags as well as Message instructions. Emulator-2-Emulator communications can be done over the emulated backplane or via EtherNet/IP

It also means that you can connect an emulated controller to an HMI or other software using Class 3 Messages. FactoryTalk Logix Echo can communicate with HMIs or other CIP-based software over EtherNet/IP or using backplane bridging and EtherNet/IP.

With Logix Echo, you can emulate the behavior of a system including the interactions between controllers and the visualization component.

This is true, even when working with remote instances of FactoryTalk Logix Echo.

Virtual SD Card

When you create an emulated controller in FactoryTalk Logix Echo, a virtual SD card is automatically created. This virtual SD card is a folder on your computer that can be used like an SD card in a physical PLC.

You can use this virtual SD card to backup and restore projects and log data just like you would with a physical SD card.

It’s worth noting that there are some differences between the physical and virtual SD cards. The most important differences are that the controller’s firmware is not stored on the virtual SD card and the content of the virtual SD card is unencrypted.

Software Development Kit (SDK) and Application Programming Interface (API)

FactoryTalk Logix Echo features an SDK that allows it to interact with other applications programmatically.

This interface allows you to integrate Logix Echo with digital twins, process simulators, and operator training systems.

It, along with the Logix Designer SDK, also unlocks the ability to do automated unit testing of software for modern development workflows.

The SDK documentation kit contains detailed explanations of all the API functions and their uses with sample code, and a NuGet package that allows access to the APIs.

FactoryTalk Logix Echo provides two APIs. The Service API is used to manage the system and perform all of the functions that can be done from the dashboard. The Controller API is used to control execution, scale time, and access tags in an emulated controller.

Snapshot Capabilities

Logix Echo allows you to take a snapshot of a controller. This stores the controller’s state at a specific point in time and allows you to restore that state in the future.

The snapshot contains the controller time, tag data, and execution context.

Snapshots are particularly useful for operator training when you want to use a training scenario that is difficult or time-consuming to recreate. They are also useful for testing since they can restore the controller to a state where a test previously failed to see if the bug is resolved.

Comparison with Studio 5000 Logix Emulate

FactoryTalk Logix Echo is Rockwell Automation’s next generation of controller emulator. It is designed to eventually replace the current generation of controller emulator, which is Studio 5000 Logix Emulate.

Let’s take a quick look at some of the key differences between these two controller emulators.

For most users, the key differences are project conversion, ethernet connectivity, and the public API so let’s start by talking about them.

Project Conversion

To download a project to Studio 5000 Logix Emulate, you have to do a lot of work to convert the project into a usable format. Specifically, you have to change the controller type and remove the hardware from the hardware configuration.

This can be quite painful when dealing with large projects.

In contrast, a Studio 5000 Logix Designer project can be downloaded directly to Logix Echo without modification and Logix Echo will emulate the hardware configuration automatically.

Ethernet Connectivity

Studio 5000 Logix Emulate does not emulate the Ethernet port of the controller. Because of this, you can’t establish communication between other emulated controllers or HMI applications to do integrated testing.

In contrast, Logix Echo does emulate the ethernet port of a controller making integrated testing for large systems possible.

Public API

Studio 5000 Logix Emulate does not have a public API which means that other applications can’t interact with Logix Emulate programmatically.

In contrast, Logic Echo’s public API makes it easy to use other applications to create controller instances, download projects to controllers, and read and write tag values. This makes it possible to integrate Logix Echo in a Continuous Integration/Continuous Deployment workflow.

Other Features

The table below shows other key differences between Studio 5000 Logix Emulate and FactoryTalk Logix Echo.

Feature Comparison

Update: As of Logix Echo version 2, you can test motion axes using CIP motion axis test mode. Check out all the new features of Logix Echo version 2 here.

Now that we know how Logix Echo compares to Logix Emulate, let’s look at the differences between Logix Echo and a physical Logix 5000 PLC.

Comparison with a Physical PLC

Logix Echo is designed to provide an emulated controller that is used for development, testing, and simulation. It is not a soft PLC and has certain limitations that a physical PLC does not.

Here’s what you can do with an emulated controller in Logix Echo;

• Download and run logic written in any programming language,
• Connect an HMI to the emulated controller (except for HMI Button Control (HMIBC),
• Configure produced and consumed tags with other emulated controllers,
• Use Message instructions,
• Use virtual axes for motion applications,
• Download a project configured for redundancy (although it will always behave as primary with no partner)

Here’s what you cannot do with an emulated controller in Logix Echo;

• Connect to physical I/O devices,
• Connect motion axes to physical drives,
• Configure produced/consumed tags with physical controllers,
• Use license-based source protection,
• Emulate a truly redundant system with primary and secondary controllers

The table below shows a more detailed breakdown of the differences between an emulated controller in Logix Echo and a physical PLC.

Behavior Differences

Controller Performance

For testing large applications, it’s good to understand the performance limits of a Logix Echo chassis.

Maximum Achievable Specifications· Class 1 Produced/Consumed messages between emulators: 20,000 PPS (packets per second)· Class 1 chassis total: 160,000 PPS. Class 3: 700 messages/second. Class 3 chassis total: 3,700 messages/second. Minimum RPI: 10ms

Note that since Logix Echo runs as a normal user program, it can and will be interrupted by other Windows services and processes. This can adversely impact performance.

Despite 99.9% of messages getting successfully transmitted/received, CIP connections will occasionally timeout due to interrupts from other Windows services.

Wrap Up

FactoryTalk Logix Echo is Rockwell Automation’s next generation of controller emulator and it offers a ton of improvements over the current solution, Studio 5000 Logix Emulate.

For most users, the most important difference is that FactoryTalk Logix Echo allows you to emulate ControlLogix 5580 controllers and allows you to download a project without modifying the hardware configuration.

The next most important feature is the emulation of the backplane and the controller’s ethernet port. This allows you to configure produced and consumed tags and Message instructions to exchange data between controllers. It also allows you to connect an emulated controller to an HMI or other software systems using Message instructions.

Logix Echo also includes an API that lets you interact with the application and any emulated controllers programmatically. This feature unlocks the ability to do automated testing of software and allows you to integrate an emulated controller into operator training simulations, emulation models, and software simulation tools.

Finally, Logix Echo offers some really useful features including the ability to capture and restore controller snapshots and support for a virtual SD card on the computer running the emulated controller.