Configuring ET 200S with WinAC RTX 2010 via PROFINET

Overview

Connecting a SIMATIC ET 200S distributed I/O station to a WinAC RTX 2010 software controller is a common requirement when engineers want to replace a hardware S7 CPU with a PC-based soft-PLC while keeping the field-proven ET 200S I/O. Because WinAC RTX behaves like a SIMATIC S7 CPU on PROFINET, the ET 200S is treated as a standard PROFINET IO device; no additional proprietary gateway hardware is required. The configuration steps live inside the same HW Config tool used for a classic S7-300/S7-400 station, with the WinAC RTX entry replacing the physical CPU in the rack.

This reference covers the complete path from hardware selection and topology, through TIA Portal V11 SP2 / STEP 7 V5.5 project engineering, to the optional Simulink SCL/DLL real-time interface that lets a Simulink model exchange process data with the WinAC RTX cycle on the RTX real-time extension.

Prerequisites

Hardware

• SIMATIC ET 200S station with a PROFINET interface module (typically IM 151-3 PN, 6ES7151-3BA23-0AB0 or later hardware revision). Head modules with PROFIBUS (IM 151-1) cannot be used for this path; you must select a PN variant.
• PM-D or PM-DC24V power module supplying the ET 200S backplane and 24 V load voltage for the electronic modules.
• Digital/analog ET 200S electronic modules mounted on a TM-E terminal module (e.g. 6ES7193-4xxx30-0AA0 family).
• Industrial Ethernet switch (SCALANCE X-200/XB-200 or any managed PROFINET-compliant switch) for shared media.
• PC/PG with a free PROFINET-capable Ethernet port (Intel I210/I350-class adapters work well; avoid Realtek adapters for hard real-time use).
• PROFINET patch cables (CAT 5e or higher) and M12 D-coded or RJ45 connectors per site standard.

Software

• WinAC RTX 2010 (6ES7671-0RC08-0YA0 or later) including the RTX real-time subsystem installation (IntervalZero RTX 2010).
• STEP 7 V5.5 with SP2 (or TIA Portal V11 SP2) for HW Config and SCL programming. TIA Portal V11 SP2 supports WinAC RTX as a station type when the WinAC option package is installed.
• SIMATIC S7-PCT (Port Configuration Tool) if the ET 200S ports need to be assigned PN port properties manually.
• Optional: MATLAB/Simulink + Simulink PLC Coder or the WinAC RTX Simulink interface addon for DLL/SCL-based real-time coupling.

ET 200S Architecture Recap

ET 200S is a bit-modular distributed I/O system with a slot-based backplane. The first slot must contain a power module, the second slot the PROFINET interface module (IM 151-3 PN), and slots 3..n accept electronic modules (DI, DO, AI, AO, technology modules, motor starters, frequency converters). Each station supports up to 63 modules and is addressed on PROFINET by:

• A unique PROFINET device name (e.g. et200s-rack-01)
• An IPv4 address (default fallback 0.0.0.0, assigned by the IO controller at startup via DCP)
• A device number assigned in HW Config

WinAC RTX 2010 Architecture Recap

WinAC RTX is a software PLC that runs on a Windows host with the IntervalZero RTX real-time extension. The RTX subsystem provides a hard real-time execution thread that is not interrupted by Windows, while user-mode tools (operator panels, OPC servers, the S7 protocol stack) keep running in Windows. The WinAC RTX engine behaves as a PROFINET IO Controller on its network adapters and supports:

• PROFINET IO with RT (real-time) class 1 and 2; IRT is supported on WinAC RTX 2010 with selected Intel NICs.
• Up to 128 PROFINET IO devices depending on license and CPU load.
• S7 communication (PUT/GET) and OPC DA/UA for HMI/SCADA connectivity.
• An SCL/DLL interface addon that exposes the cyclic OB1 / OB35 process image to a Windows DLL called from a non-RT thread — this is the mechanism used by Simulink integration.

PROFINET Connection Topology

The reference topology is a single line with the WinAC RTX PC as the IO controller and one or more ET 200S stations as IO devices. Because WinAC RTX binds the PROFINET stack to a physical Ethernet adapter, you should use a dedicated NIC for PROFINET to keep Windows traffic separate.

For deterministic IRT operation, the WinAC RTX PROFINET NIC, the switch, and the ET 200S IM 151-3 PN must all be configured for the same sync domain. For RT class 2 / 1 (typical ET 200S use case) the switch requirement is relaxed to PROFINET-conformant cut-through.

Step-by-Step Configuration

1. Install the RTX runtime first, then WinAC RTX. The RTX installer (IntervalZero) must be present before WinAC RTX will install, and both must be reinstalled on RTX version changes. Verify with the RTX control panel applet that the RT subsystem starts cleanly without yellow triangles.
2. Identify the PROFINET NIC. In Windows Device Manager, note the PCI bus index and friendly name of the Ethernet adapter that will carry PROFINET. Disable Windows power management for this adapter and disable any protocol offloading that could interfere with RT frames.
3. Open STEP 7 V5.5 / TIA Portal V11 SP2. Create a new project (ET200S_WinAC.project). The device & network view differs slightly between STEP 7 V5.5 HW Config and TIA Portal V11 SP2; the TIA Portal flow is shown below because it matches the user's installed version.
4. Insert the WinAC RTX station. In the TIA Portal project tree, choose Devices & networks > Add new device > PC systems > SIMATIC WinAC RTX. Place the station; TIA Portal will create a rack with the WinAC RTX slot. Bind the PROFINET interface to the NIC identified in step 2.
5. Add the ET 200S station. From the hardware catalog, navigate to Distributed I/O > ET 200S > Interface modules > PROFINET > IM 151-3 PN. Drag the head module to the network view.
6. Drag a PROFINET connection from the WinAC RTX PROFINET port to the IM 151-3 PN port. TIA Portal assigns the ET 200S a default device name; rename it to something project-meaningful, e.g. et200s-line1.
7. Configure ET 200S slots. Open the ET 200S device view and populate slots 1..n with PM-D, DI/DO/AI/AO modules. Match the GSD-based module catalog numbers to the installed hardware; mismatches cause a configuration fault at startup.
8. Assign I/O addresses. In the device view's Properties pane, the input and output byte addresses are mapped into the WinAC RTX process image. Defaults start at IB 0 / QB 0; remap to avoid collision with WinAC RTX system reserves (IB 0..15 / QB 0..15 are typically reserved for onboard I/O of the slot PLC).
9. Assign PROFINET device name. Use Online > Accessible nodes or SIMATIC S7-PCT to assign the configured name et200s-line1 to the IM 151-3 PN. The MAC-address-tagging step is mandatory; the device boots with an empty name and only accepts frames once a DCP name has been written.
10. Compile and download. Compile the WinAC RTX station and the ET 200S station, then download HW Config to the WinAC RTX PC. The WinAC RTX service must be running in STOP before download and transitioned to RUN after.
11. Verify cyclic IO. Monitor the ET 200S device diagnostics in TIA Portal Online & diagnostics. The slot status must show green check marks for every configured module; a red X indicates a module mismatch or a removed module.

Simulink DLL/SCL Real-Time Interface

When the goal is closed-loop real-time data exchange between a Simulink model and the WinAC RTX cycle, the standard addon exposes two integration paths:

• SCL blocks in the WinAC RTX project that read/write from the Simulink-shared memory region at the OB1 or OB35 cycle.
• Compiled DLL generated from a Simulink model that is loaded by WinAC RTX through its interface addon; the DLL's inputs and outputs are bound to process-image symbols compiled into the SCL.

Typical OB35 cycle is 10 ms; Simulink solver step is fixed to a multiple of the OB35 period (e.g. 10 ms, 20 ms, 50 ms) to keep the two timers phase-aligned. A practical SCL skeleton for reading a shared-memory input from the DLL is:

// SCL: readSimulinkInput.fc
FUNCTION readSimulinkInput : REAL
VAR_INPUT
    pSharedMem : POINTER TO REAL;   // bound by WinAC RTX addon
END_VAR
BEGIN
    // Shared memory is refreshed by the Simulink DLL in non-RT thread.
    // The addon handles memory barriers; we just read.
    readSimulinkInput := pSharedMem^;
END_FUNCTION

On the Simulink side, the generated DLL exports a step() function and a set of memory-mapped inputs/outputs that the addon wires to the same addresses. The Simulink model runs in a Windows thread (non-RT), but the WinAC RTX code reads the freshest value on every OB35 tick, giving bounded latency equal to the OB35 period.

Diagnostics and Verification

After commissioning, verify the link with three independent checks:

1. Station-level LEDs on the IM 151-3 PN: green BF (bus fault) off, green SF (system fault) off, green LINK on every active port. Yellow flashing on the maintenance LED indicates a configuration mismatch.
2. TIA Portal online diagnostics: Online & diagnostics > PROFINET diagnostics. The ET 200S node should show connection status Established, no recorded alarms, and a fresh cycle time within ±5% of the configured send clock (typically 1 ms).
3. Process-image mirror test: Force a known pattern on an ET 200S DO module from TIA Portal and read back the corresponding DI wired to that DO. The mismatch must be zero over at least 10 000 OB cycles.

Troubleshooting Matrix

Performance and Cycle Considerations

For ET 200S with the IM 151-3 PN, the minimum PROFINET send clock is 1 ms; typical applications use 1 ms or 2 ms. The WinAC RTX OB35 period should be an integer multiple of the send clock, and the total cycle time must not exceed the OB35 watchdog (default 100 ms). With one ET 200S station carrying ~16 bytes of I/O, the RT frame utilization stays below 5%, leaving plenty of headroom for additional IO devices.

Safety Notes

Reference Materials

Engineers performing this integration should consult the SIMATIC ET 200S system manual, the WinAC RTX 2010 function manual, and the TIA Portal V11 SP2 help on PROFINET IO configuration. Verify device catalog numbers and firmware revisions against the latest Siemens Industry Online Support entries before procurement and commissioning.