Interfacing SPPA-T2000 FUM Modules with SIMATIC PCS 7: Migration Architecture and Driver Block Integration

Direct integration of legacy SPPA-T2000 (TELEPERM M / AS 620B) Functional Modules (FUM) into a standard SIMATIC PCS 7 system is not supported natively via off-the-shelf PCS 7 APL driver generators. FUM modules (such as FUM 210, FUM 230) utilize specialized interface modules like the IM 616 to communicate over proprietary or customized PROFIBUS DP profiles originally designed for power generation turbines and utility boilers. To integrate FUM I/O into PCS 7, utilities and power plant engineers must either utilize the specialized Siemens SPPA-T3000 / PCS 7 migration package with custom adFEM / FUM driver libraries, access the process data via an intermediary S7-400H / AS 620B gateway controller, or execute a phased hardware migration to ET 200M / ET 200SP HA.

Overview of SPPA-T2000 and FUM Module Architecture

In power generation facilities, control systems such as TELEPERM M and SPPA-T2000 (formerly AS 620) utilized dedicated hardware known as Function Modules (FUM). Unlike standard process I/O cards that only digitize raw voltages, FUM modules (e.g., FUM 210 analog processing, FUM 230 binary control, and FUM 280 turbine control) contain autonomous onboard microprocessors capable of executing localized high-speed closed-loop control, sensor validation, and actuator positioning independently of the central automation station.

As utilities modernize aging power plants, engineers frequently evaluate whether existing FUM racks can be retained and interfaced directly with a new SIMATIC PCS 7 DCS to avoid field recabling costs.

The Role of the IM 616 Interface Module on PROFIBUS DP

During the mid-lifecycle evolution of the AS 620B system, Siemens introduced the IM 616 interface module. The IM 616 acts as a bridge between the proprietary FUM subrack backplane and an Industrial PROFIBUS DP master subnet:

PROFIBUS DP Coupling: The IM 616 interfaces redundant S7-400H or AS 620B controllers over standard RS485 PROFIBUS lines using specialized GSD files.
Data Structure: The IM 616 maps complex internal FUM data structures (analog measurements, limit checks, diagnostic words, and actuator feedback) into packed byte telegrams.
Absence from Standard PCS 7 Released Module List: Because the IM 616 was proprietary to the Siemens Power Generation (Siemens Energy / KWU) division, it was never incorporated into the standard 'SIMATIC PCS 7 - Released Modules' catalog.

Driver Compatibility: Standard PCS 7 vs Specialized Power Generation Libraries

In a standard PCS 7 engineering environment, the driver generator (Generate Module Drivers) automatically reads the HW Config topology and interconnects diagnostic blocks (MOD_D1, RACK, CH_AI). Because FUM modules and IM 616 lack standard PCS 7 driver templates:

Compilation Rejection: If an IM 616 GSD file is placed into HW Config in a standard PCS 7 project, driver compilation will generate errors stating that no driver family exists for this slave.
The adFEM / FUM Migration Library: Siemens Energy developed proprietary add-on libraries (such as the adFEM library and AS 620 migration blocks) for Step 7 / PCS 7. These libraries provide specialized CFC driver blocks that unpack the IM 616 data words into standard process engineering signals.
Licensing: These specialized migration libraries are restricted engineering packages distributed exclusively through Siemens Energy service agreements.

Migration Strategies: Intermediary Controller vs Direct I/O Replacement

Power generation modernization projects typically adopt one of two paths:

Intermediary Gateway Architecture: The existing FUM racks remain connected to an existing AS 620B / S7-400 controller. The controller acts as an intelligent communication gateway, forwarding aggregated process values and commands to the new PCS 7 system via high-speed Industrial Ethernet (S7 connections or OpenIE).
Phased Field Modernization (Recommended): Replace the FUM racks with modern ET 200M or ET 200SP HA distributed I/O stations. Siemens provides pre-manufactured front-connector adapters and marshaling termination assemblies that mate directly to existing TELEPERM / FUM field terminal blocks, eliminating the need to ring out or pull new field cables.

Comparison of FUM Integration Approaches in Process Plants

The following table compares architectural options for handling legacy SPPA-T2000 FUM modules during a PCS 7 modernization:

Integration MethodCapital ExpenditureEngineering ComplexityDCS Driver SupportLong-Term Lifecycle RiskDirect FUM with Specialized LibraryLow (Retains field hardware)Very High (Custom GSD and Energy blocks)Requires specialized Siemens Energy supportHigh (FUM modules are discontinued)Intermediary Controller GatewayModerateModerate (Configures S7 cross-communication)Standard S7 communication blocksModerate (Maintains legacy controller)Phased Migration to ET 200M / SP HAHigher initial capitalStandard (Native PCS 7 APL engineering)100% Native APL driver generationNone (Active, long-term lifecycle)

Commercial Accuracy Disclaimer: Software order numbers (MLFBs), package structures, and hardware capacity prerequisites vary across PCS 7 versions and hardware platforms. System integrators must confirm exact software entitlements and licensing requirements against the official Siemens Catalog CA 01 and obtain an authorized Siemens distributor quotation prior to purchasing.

Verification

Verify data integrity when interfacing specialized power generation hardware:
1. In HW Config, verify that the slave configuration for the IM 616 or gateway controller shows status 'Active / No Fault' in online diagnostic mode.
2. In CFC, monitor the unpacked analog and discrete process values originating from the FUM subrack; verify that raw integer conversions match calibrated field instrument values.
3. Simulate a sensor wire break on a field channel; verify that the FUM module sets the diagnostic fault bit and that the CFC driver block triggers an invalid quality code (0x00 Bad or 0x28 Bad Process Related).
4. Verify that WinCC faceplates reflect sensor health and operator commands without communication latency.

Limitations and Operational Precautions

Standard industrial PCS 7 support channels (Customer Support) do not support SPPA-T2000 FUM modules or IM 616 hardware. Inquiries regarding FUM firmware, replacement submodules, and specialized migration software must be directed to Siemens Energy Power Plant Automation. Do not attempt to use standard ET 200M function module drivers (such as FM 350 counter blocks) to interface FUM hardware, as memory structures and backplane communication protocols are incompatible.

Engineer FAQ

Are FUM modules listed in the 'PCS 7 - Released Modules' manual?

No. FUM modules and the IM 616 interface belong to the SPPA-T2000 power generation product family and are not included in the standard SIMATIC PCS 7 released module list.

Can I use standard APL channel blocks like Pcs7AnIn with FUM modules?

Not directly. Standard Pcs7AnIn blocks require standard Siemens process image partitions and diagnostic drivers generated by the PCS 7 driver generator. FUM data must first be unpacked via specialized conversion blocks or user logic.

What is the difference between FUM modules and standard S7-300 FM modules?

S7-300 FM modules (e.g., FM 350, FM 355) are standard catalog components designed for Step 7 and PCS 7. FUM modules are specialized, rack-based controllers designed for TELEPERM M and SPPA-T2000 power generation applications.