Resolving SIMIT Virtual Controller CPU 410-5H Substitution and MLFB Mismatch on Download

When compiling a simulation model containing an AS 410-5H in early SIMIT Virtual Controller (VC) releases, SIMIT displays a warning that the CPU 410 is unsupported and will be substituted by a CPU 417-4. Subsequent hardware configuration downloads from SIMATIC Manager fail with an MLFB order number mismatch error because the offline project targets a CPU 410-5H (6ES7410-5HX08-0AB0) while the emulator presents a CPU 417-4 (6ES7417-4XT05-0AB0). To resolve this, engineers must bypass the Hardware Configuration download and execute 'Download Changes' or 'Charts Only' from the CFC Editor, or upgrade to SIMIT V9.1 SP1 / V10.0, which provides native, fully certified emulation of the CPU 410-5H platform.

SIMIT Virtual Controller Emulation Architecture

The SIMIT Virtual Controller (VC) emulates the behavior of SIMATIC S7-300, S7-400, and S7-410 controllers on a Windows PC. Unlike S7-PLCSIM which runs as a single desktop application, SIMIT VC executes multiple virtual controllers simultaneously as real-time Windows services communicating over virtual Ethernet interfaces.

In early releases (SIMIT V8.x through early V9.1), the Virtual Controller kernel emulated the S7-400 V5.x instruction set. Because the CPU 410-5H features specialized firmware and System Expansion Card (SEC) licensing structures, early SIMIT compilers automatically substituted CPU 410 instances with a generic high-capacity CPU 417-4.

Root Cause of CPU 410-5H Substitution and MLFB Collisions

The table below details the conflict occurring during the download sequence:

Engineering StepAction / ToolResulting Behavior / Error DiagnosticSIMIT HW ImportSIMIT imports HW Config containing CPU 410-5H (6ES7410-5HX08-0AB0).SIMIT warning: 'Certain properties of CPU-410 are not supported and will be replaced by CPU-417'Virtual Controller StartSIMIT VC starts virtual instance as CPU 417-4 (6ES7417-4XT05-0AB0).Online virtual controller reports CPU 417-4 identity to the network.HW Config DownloadSIMATIC Manager attempts full HW Config download to the virtual node.Download Aborted: 'The target module has a different order number than the offline configuration'.CFC Chart DownloadCFC Editor downloads compiled user program (Download Changes / Charts Only).Successful Download: CFC downloads code directly to user memory, ignoring MLFB differences.

Workarounds and Migration to Native CPU 410 Support

Depending on the installed SIMIT release, two solutions exist:

Method 1: Download Charts Only from CFC (No Hardware Download)

If using legacy SIMIT without native CPU 410 support:

In SIMATIC Manager, do not download the Hardware Configuration (HW Config) to the virtual controller.
Open the Continuous Function Chart (CFC) editor.
In CFC, click the Download icon (or select PLC -> Download...).
In the download dialog, select Changes only (or Entire program - Charts only).
The CFC compiler bypasses the hardware MLFB handshake and successfully downloads all FBs, FCs, DBs, and run sequences into the virtual CPU 417 memory.

Method 2: Upgrade to SIMIT V9.1 SP1 / V10.0 (Native Support)

Siemens added native CPU 410-5H firmware emulation in SIMIT V9.1 SP1 and SIMIT V10.0:

SIMIT VC natively recognizes MLFB 6ES7410-5HX08-0AB0.
Full HW Config downloads, communication connections, and redundant AS 410-5H pairs can be downloaded directly from SIMATIC Manager without substitution warnings.

Procurement Schedule for SIMIT Virtual Controller

The following Equipment Schedule specifies the relevant order numbers for SIMIT VC licensing:

Software Packages:
- SIMIT Engineering V9.1 (Software Media):         6DL8913-0AK10-0AB5
- SIMIT Virtual Controller (1 VC License):         6DL8913-0BL00-0AB5
- SIMIT Virtual Controller (5 VC Pack):            6DL8913-0BN00-0AB5
- SIMIT V9.1 to V10.0 Upgrade Package:             6DL8913-0AE00-0YB5

[!IMPORTANT]
Commercial Accuracy Disclaimer: SIMIT Virtual Controllers are licensed per emulated controller instance. Simulating a redundant AS 410-5H automation station requires two Virtual Controller licenses. Final software entitlements and MLFBs must be validated against the applicable Siemens ST PCS 7 Catalog and authorized distributor quotations.

Verification

To verify that the simulation operates correctly:

Start the SIMIT simulation project containing the Virtual Controller.
Confirm that the virtual controller status indicator transitions to solid green RUN.
In CFC, initiate a download of charts: verify download reaches 100% completion without error.
Open CFC Online Test mode: verify live process values and block executions update dynamically.
Inject a simulated field input from SIMIT: confirm the CFC logic responds immediately.

Limitations and Operational Precautions

Operational boundaries when virtualizing CPU 410 controllers:

HW Config Features Omitted: When using CPU 417 substitution, specific CPU 410 features (such as onboard PROFINET system redundancy R1 and System Expansion Card PO limits) are not emulated.
Redundant AS 410-5H Coupling: Simulating bumpless CPU redundancy switchover requires SIMIT V10.0 or higher with paired virtual controllers.
Classic S7-PLCSIM Alternative: If SIMIT VC licenses are unavailable, classic S7-PLCSIM V5.4 can be used, as it accepts CPU 410 programs without checking hardware MLFBs.

Engineer FAQ

Why does SIMIT replace CPU 410 with CPU 417 in older versions?

Earlier SIMIT Virtual Controller kernels did not include the specific firmware definitions and PROFINET interfaces of the CPU 410-5H, substituting the closest high-memory S7-400 processor (CPU 417-4).

How can I download to the virtual controller if HW Config fails with an order number mismatch?

Do not download HW Config. Download only the charts from the CFC Editor (Download Changes or Charts only). CFC bypasses hardware order number checks.

Which SIMIT version officially introduced native CPU 410-5H emulation?

Native CPU 410-5H emulation was officially introduced in SIMIT V9.1 SP1 and expanded in SIMIT V10.0.

Does SIMIT Virtual Controller emulate the CPU 410 System Expansion Card (SEC)?

In native CPU 410 emulation (SIMIT V10+), the Virtual Controller automatically allocates maximum memory capacity (2,600 POs) without requiring physical SEC licenses.