Configuring Legacy CPU 414-4H and CPU 412-3H Controllers in SIMATIC PCS 7 V9.1

In SIMATIC PCS 7 V9.1, legacy controllers such as the CPU 414-4H and CPU 412-3H do not appear in the New Project Wizard because project creation templates default exclusively to the modern CPU 410-5H standard. However, released legacy S7-400H hardware revisions remain fully configurable by inserting a standard SIMATIC 400 Station in SIMATIC Manager and selecting the certified CPU MLFB and firmware from the STEP 7 Hardware Catalog according to the official Released Modules documentation.

Hardware Scope and the PCS 7 New Project Wizard Template Behavior

When creating a new process control project in SIMATIC PCS 7 V9.1, engineers frequently notice that the New Project Wizard (PCS 7 Wizard) only offers the CPU 410-5H Process Automation controller in its drop-down selection list:
* Legacy fault-tolerant controllers—such as the CPU 414-4H and CPU 412-3H—are omitted from the wizard interface.
* This omission does not indicate that all existing S7-400H hardware is immediately obsolete or unsupported in PCS 7 V9.1.
* Rather, the wizard is designed solely as a rapid-templating aid configured with current production hardware baselines. Legacy automation stations are engineered using standard manual station insertion in SIMATIC Manager.

Released Modules Verification: Confirming MLFB and Firmware Support

Before configuring or maintaining an existing S7-400 controller in PCS 7 V9.1, engineers must cross-check the exact manufacturer Order Number (MLFB) and firmware version against the official documentation:
* Consult the Siemens manual: SIMATIC PCS 7 - Released Modules V9.1.
* Supported Revisions: Later generation S7-400H CPUs (such as 6ES7414-5HM06-0AB0 or 6ES7412-5HK06-0AB0 with firmware V6.0) are fully released for engineering and maintenance in PCS 7 V9.1.
* Phased-Out Revisions: Older legacy CPUs (such as the legacy 6ES7414-4HJ04-0AB0 with firmware V4.5) have reached phased-out / discontinued manufacturer status and are not certified for new PCS 7 V9.1 installations. Never declare hardware obsolete without verifying the exact MLFB and firmware release status.

Manual Station Engineering Procedure in STEP 7 HW Config

To configure a CPU 414-4H or CPU 412-3H station in a PCS 7 V9.1 multiproject:
1. Open SIMATIC Manager and open your target Multiproject.
2. Cancel or bypass the New Project Wizard.
3. In the project tree, right-click the project folder and select:
Insert New Object -> SIMATIC 400 Station (or SIMATIC H Station for redundant pairs).
4. Double-click the Hardware object to launch STEP 7 HW Config.
5. In the Hardware Catalog, navigate to:
SIMATIC 400 -> RACK-400 -> UR2-H (for redundant racks) or UR1 / UR2 (for single racks). Drag the rack into the configuration window.
6. Place the Power Supply module (e.g., PS 407).
7. In the Hardware Catalog, navigate to:
SIMATIC 400 -> CPU 400 -> CPU 414-4H (or the exact MLFB matching your physical controller, e.g., 6ES7 414-5HM06-0AB0).
8. Select the exact firmware version installed on the controller and place the CPU into the designated rack slot.
9. Configure memory card parameters, MPI/DP interfaces, and sync submodules.
10. Save and Compile HW Config: the station generates valid System Data Blocks (SDBs) and integrates seamlessly with CFC and APL.

Lifecycle Considerations: Legacy S7-400H vs. Modern CPU 410-5H

When evaluating existing hardware in operational facilities:
* Engineering Continuity: Verified legacy CPUs can continue operating under PCS 7 V9.1, preserving existing capital investments in field wiring, ET 200M racks, and S7-400 power supplies.
* Capacity and Memory: S7-400H CPUs rely on physical RAM/Flash memory cards with fixed code/data work memory partitions, whereas the modern CPU 410-5H features high-performance unified memory scalable via the System Expansion Card (SEC).
* Future Expansions: For new plant expansions or complete unit modernizations, Siemens recommends migrating to the CPU 410-5H to benefit from dynamic memory allocation, faster processing, and long-term lifecycle support. Final purchasing decisions and migration paths should always be verified with an authorized Siemens distributor.

Verification

In HW Config, execute Station -> Consistency Check: confirm that the S7-400 station reports zero errors and zero warnings.
In SIMATIC Manager, create a test CFC chart under the S7 Program folder and insert standard APL blocks (MotL, Pcs7AnIn).
Execute an AS compile (Entire Program): verify that the compiler successfully generates machine blocks for the target CPU architecture.
Open Target System -> Diagnostics/Setting -> Module Information online: confirm that the configured MLFB and firmware match the physical controller.

Limitations and Operational Precautions

Redundant S7-400H systems require identical CPU MLFBs, identical firmware releases, and identical sync submodule hardware in both racks.
Older CPU 414-4H hardware revisions do not support Type Change in RUN (TCiR) or the latest PROFINET system redundancy features (S2/R1) available on modern CPU 410 controllers.
Always back up the multiproject archive before attempting hardware catalog updates or module migrations.

Engineer FAQ

Why does the PCS 7 V9.1 New Project Wizard only display CPU 410-5H?
The wizard templates standardize on modern hardware baselines; legacy CPUs must be added manually in HW Config.
Can a CPU 414-4H run PCS 7 Advanced Process Library (APL) blocks?
Yes, released S7-400H CPUs execute standard APL blocks identically to CPU 410 controllers within their memory limits.
Where can I find the official list of supported modules for PCS 7 V9.1?
In the official Siemens manual titled SIMATIC PCS 7 - Released Modules V9.1 published on SIOS.
Is the CPU 414-4HJ04 supported in PCS 7 V9.1?
The legacy CPU 414-4HJ04 (firmware V4.5) is phased out and not released for PCS 7 V9.1; newer revisions (e.g., 414-5HM06) are supported.
How do I add a redundant S7-400H station manually in SIMATIC Manager?
Right-click the project folder and select Insert New Object -> SIMATIC H Station, then configure the UR2-H rack in HW Config.
Does using a legacy S7-400H CPU require different AS RT Process Object licenses?
No, AS RT PO software licenses operate identically across all S7-400 and CPU 410 controllers.
Do legacy S7-400 CPUs require a System Expansion Card (SEC)?
No, legacy S7-400 CPUs do not use SEC cards; they use standard Siemens S7-400 Flash or RAM memory cards.
What happens if the firmware selected in HW Config does not match the physical CPU?
The hardware download will generate a firmware mismatch warning, and online diagnostic features may be impaired.
Can I replace a failed CPU 414-4H with a CPU 410-5H in an existing rack?
CPU 410-5H requires distinct sync modules and firmware configurations; migrating to CPU 410 involves updating HW Config and connection parameters.
What is the recommended commercial validation step before purchasing replacement CPUs?
Validate active manufacturer product lifecycle status, spare part availability, and MLFBs via the Siemens Industry Mall and authorized distributor quotation.

Technical References

SIMATIC PCS 7 - Released Modules V9.1 Manual (A5E50039864)
SIMATIC S7-400 Fault-Tolerant Systems S7-400H System Manual
Siemens Industry Online Support Entry: S7-400 CPU Selection in PCS 7 Wizard (Entry ID 299189)
Siemens Industry Mall: S7-400 Product Lifecycle and Milestone Status

Related Tags

PCS 7, S7-400H, CPU 414-4H, CPU 412-3H, HW Config, Hardware Catalog, Released Modules, Lifecycle, Wizard, Architecture

Configuring Legacy CPU 414-4H and CPU 412-3H Controllers in SIMATIC PCS 7 V9.1