SIMATIC WinAC RTX F – Fail-safe S7 software controller

SIMATIC WinAC RTX F is the fail-safe SIMATIC software controller for PC-based automation and permits both standard and fail-safe control tasks to be performed on the PC.

Area of application

SIMATIC WinAC RTX F permits simple implementation of safety systems on PC-based solutions, and satisfies maximum safety requirements and compliance with relevant standards: EN 954-1 up to Cat. 4, IEC 62061 up to SIL 3, and EN ISO 13849-1 up to PL e.

The fail-safe software controller is particularly suitable for automation tasks in which, in addition to standard and fail-safe control functions, parallel data processing and the integration of the user’s own technological functions are to be implemented on one platform and the openness of Windows is to be exploited.

To ensure the high performance of the complete system the latest PC technologies such as Dual Core are supported, in which one core is used for Windows applications and the other core exclusively for SIMATIC WinAC RTX F. The integration of C/C++ programs into the WinAC RTX control program provides access to all hardware and software components of the PC, creating an extremely flexible solution. The performance of WinAC RTX F is limited only by the PC platform used.

Apart from the software-only controller, particularly rugged and ready-to-run embedded bundles are also available, preinstalled with SIMATIC WinAC RTX F and Windows XP Embedded or Windows Embedded Standard. Whether on the basis of a modular embedded controller, a DIN rail PC or a Panel PC, the application ultimately determines the choice of hardware to be used.

Standardized engineering and the easy portability of the user software between the different solutions also contribute to the overall security of investment and flexibility.To the top of the page


With the new SIMATIC WinAC RTX F software controller, Siemens links its long-term competence in standard and safety engineering with the openness of a PC-based system.

With WinAC RTX F you can benefit from the advantages of SIMATIC Safety Integrated

  • System-wide integration of safety into the standard technology even in PC-based solutions:
    – One PC-based controller for both standard and fail-safe automation
    – Engineering in the familiar STEP 7 environment and with the Distributed Safety option 
      package and choice of off-the-shelf blocks certified by the German Technical 
      Inspectorate or blocks you have created yourself
    – Fail-safe communication via the globally field-proven PROFINET or PROFIBUS 
      communication standards, with the PROFIsafe profile 
    – Space-saving design thanks to the combination of fail-safe and standard I/Os in one 
  • Approval for the most stringent safety requirements, such as Cat. 4 of EN 954, 
    SIL 3 of EN 62061 and PL e of EN ISO 13849-1, regardless of the hardware used
  • The safety function can be assessed quickly and conveniently using the Safety Evaluation. All safety-related data of the products is available through an integrated database.

as well as the advantages of WinAC RTX, the SIMATIC software controller

  • Performance of PC-typical applications and automation tasks on just one platform
  • Installation possible on all current x86 PCs
  • Ready-to-run embedded bundles, consisting of rugged, maintenance-free hardware and preinstalled, preconfigured software
  • Security of investment through the use of SIMATIC IPCs and embedded bundles with long-term availability
  • The high performance of WinAC RTX also enables high-speed control solutions to be implemented with minimal processor loading.
  • Utilization of the continuous innovation and performance improvement of PCs
  • Simple communication through integral network interfaces
  • Simple use of business software (e.g. Microsoft Office) and user’s own powerful software (e.g. C++, Visual Basic, Java, etc.)
  • Strict real-time for automation tasks

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Layout and function

As in the fail-safe SIMATIC controllers, the engineering is implemented with STEP 7 and the Distributed Safety option package. This means that existing know-how can continue to be used.


SIMATIC WinAC RTX F executes on all x86 hardware platforms with Windows XP Professional and is optimally matched to SIMATIC Industrial PCs. Especially when used on embedded PC platforms, such as the SIMATIC IPC 427C, the SIMATIC HMI IPC 477C or the SIMATIC S7-mEC with Windows Embedded Standard 2009, economical and extremely rugged solutions can be achieved. WinAC RTX F uses the main memory of the PC and offers a program backup in the data medium (e.g. HDD, CompactFlash card, SSD). Non-cyclic data, such as production parameters or recipe data, can be stored permanently on the data medium (e.g. HDD, CompactFlash card, SSD) of the PC with the help of system functions (SFC 82 – 84). In addition, all data can be held retentively in conjunction with an uninterruptible power supply (UPS).

Connection of the I/O

WinAC RTX F can control the distributed I/O not only via PROFIBUS, but also via PROFINET.

The I/O is connected via PROFIBUS DP at up to 12 Mbit/s via the integral DP interface of the SIMATIC IPCs or the embedded bundles. In addition, communications processors (CP 5611 A2/ 5613 A2) can also be used that support as many as four PROFIBUS lines with up to 500 slaves.

The connection to PROFINET is via Ethernet chipsets for PROFINET IO with RT:

Interface nameChipset
Intel® Pro/1000 CT Gigabit DesktopIntel®82574L
Intel® PRO/1000 PT dual port server adapterIntel® 82571EB

or via a CP 1616 (PCI) or CP 1604 (PCI-104) communications processor.

The SIMATIC IPCs or the embedded bundles feature an optional integrated PROFINET interface, while it is standard for the S7-mEC RTX F.

In addition, WinAC RTX F also supports the system function isochronous mode. With isochronous mode, high-speed, time-dependent applications such as closed-loop controls can also be implemented with distributed I/O. This means that in addition to the control job other functions can be integrated into a PC or smaller, more economical PCs can be used for the same job.
With the new version WinAC RTX 2010 further PROFINET functions are available e.g. shared device, media redundancy and webserver functionality.To the top of the page

Technical data

Dimensions (mm)
Order no. stem6ES7 671-1RC.0
RAMdepends on PC
Execution times
Bit operation0.004 μs *)
Word operation0.003 μs *)
Fixed-point operation0.003 μs *)
Floating-point operation0.004 μs *)
Bit memories, timers, counters
Bit memory16 KB
S7 timers/S7 counters2048/2048
IEC timers/IEC counters
Address ranges
Number of I/Os (bytes)16348/16348
Process image I/O (bytes)8192/8192
Digital channels (central)
Analog channels (central)
DP interfaces
DP master systems (int./CP)depends on PC
DP slave
Plug-in interfaces
Isochronous mode
PROFINET interface
ISO-on-TCP (RFC 1006)
Web server
Open User Communication
Isochronous mode

*) Depends on PC hardware used; reference platform Pentium IV; 2.4 GHz

A second timer is required for fail-safe communication. Most PCs already have such a timer.