Resolving Missing Running Feedback on SIMOCODE pro V Blocks After PCS 7 CEMAT Upgrade

When SIMOCODE pro V motor management units fail to provide running feedback (FEED_ON2 = 0) following a SIMATIC PCS 7 and CEMAT library upgrade from V6.1 to V8.2, the failure is caused by an inconsistent library block type update between the project-specific PRO_CEM and standard ILS_CEM libraries, or mismatched cyclic telegram mapping. In CEMAT V8.2, block C_SIMOS evaluates specific current thresholds and feedback bits in cyclic telegram word 1. If C_SIMOS was updated from PRO_CEM while SIMOCODE parameters reflect standard ILS_CEM mapping, feedback evaluates as false. To resolve this, standardize on C_SIMOS from ILS_CEM, execute a clean block type update, and align SIMOCODE ES cyclic send data.

Architecture of SIMOCODE pro V Integration in CEMAT and PCS 7

In heavy industries (cement, minerals, mining), the SIMATIC PCS 7 CEMAT industry library coordinates large medium-voltage and low-voltage motor drives via SIMOCODE pro V units (3UF7010-1AB00-0). The integration relies on cyclic PROFIBUS DP or PROFINET communication exchanging control words (start/stop commands) and status words (running feedback, current, thermal overload, fault flags).

In CEMAT architectures, the dedicated driver block C_SIMOS (or modern FbSwtMMS / C_SIMO_A) decodes cyclic status telegrams and supplies operational signals—such as running feedback FEED_ON2—to the main technological motor block C_DRIVE_1D.

Root Causes: PRO_CEM vs ILS_CEM Library Branch Mismatch

During system migrations from legacy PCS 7 V6.1 to V8.2 (AdvLibCE family), engineering multiprojects frequently contain two separate CEMAT library sources:

ILS_CEM (International Standard Library): The standard generic CEMAT release adhering to standardized Siemens SIMOCODE parameter mappings.
PRO_CEM (Project / Client-Specific Branch): Customized branches (e.g., customized for Holcim or specific corporate standards). In PRO_CEM, C_SIMOS was customized to derive running feedback strictly from internal motor current measurements exceeding a threshold (I > I_min) rather than contactor auxiliary contacts.

If the AS project was updated with C_SIMOS from PRO_CEM, but the physical SIMOCODE pro V devices remained parameterized with standard ILS telegrams lacking current threshold flags, FEED_ON2 remains 0 permanently.

Cyclic PROFIBUS Telegram Mapping and Current-Based Feedback

When upgrading from GSD V1.2 to GSD V1.3/V1.5 in STEP 7 HW Config:

Verify the configured Cyclic Send Data (Basic Type 1 or 2) in SIMOCODE ES.
Bit 0 of Byte 0 typically represents Status On1 / Running.
If the PLC block expects the current measurement to confirm running status, verify that current measuring modules (3UF7100-1AA00-0) are connected and parameter I > I_min is evaluated.

Step-by-Step Block Type Standardization and Update Workflow

Follow this procedure to restore uniform feedback across all drives:

Determine the Authorized Library Source:
- Confirm whether the plant standard mandates ILS_CEM or client-specific PRO_CEM.
Update Block Types in Master Data Library:
- In SIMATIC Manager, copy the verified C_SIMOS block from ILS_CEM into the Master Data Library Blocks folder.
Execute Global Block Type Update:
- In the Master Data Library, select Options > Manage Block Types....
- Select C_SIMOS and click Update Block Types.
- Select all target AS multiprojects; confirm interface adaptation.
Recompile Charts and Download:
- Note: If block interface attributes changed between libraries, an Entire Program Download (in CPU STOP) is required.
- Plan a maintenance shutdown, perform full compile and download.

Comparison of SIMOCODE Driver Blocks in CEMAT and APL

The table below contrasts SIMOCODE driver blocks across library architectures:

Library FamilyDriver BlockApplication ScopeFeedback SourceCurrent EvaluationCEMAT ILS_CEMC_SIMOSSIMOCODE pro V (Standard)Contactor & Current BitCyclic current analog wordCEMAT PRO_CEMC_SIMOS (Custom)Specific corporate standardsStrictly current thresholdInternal threshold evaluationCEMAT ILS_CEMC_SIMO_ASIMOCODE pro C (Small drives)Contactor auxiliary bitBasic current percentagePCS 7 Standard APLFbSwtMMS (FB 1907)Standard APL MotL drivesConfigurable (Digital / Current)Full motor diagnostic dataset

Verification

Verify running feedback restoration in CFC and OS:

Start the drive physically from the plant floor or local control box.
In CFC, open the chart containing C_SIMOS online in test mode.
Confirm that FEED_ON2 transitions from 0 to 1.
Inspect the parent motor block C_DRIVE_1D; confirm the running state latches and does not trip on feedback monitoring timeout.
On the WinCC OS faceplate, confirm the motor symbol changes to running green.

Limitations and Operational Precautions

Observe the following safeguards when updating CEMAT block types:

CPU Stop Requirement: Swapping block types across different library families alters block interface structures and instance DB allocations, making a delta download in RUN impossible.
SIMOCODE ES Parameter Backup: Always upload and archive the active device parameters using SIMOCODE ES before modifying HW Config GSD versions.
Standardized Library Discipline: Never mix blocks from PRO_CEM and ILS_CEM ad-hoc; enforce strict library version control.

Engineer FAQ

Why did C_SIMO_A work fine while C_SIMOS had feedback problems?

Because C_SIMO_A (for SIMOCODE pro C) existed only in the standard ILS_CEM library and used standard contactor feedback, whereas C_SIMOS was updated from the custom PRO_CEM library which expected specialized current-threshold feedback.

Can I update C_SIMOS from PRO_CEM to ILS_CEM via Download Changes in RUN?

No. Because the block headers and internal parameter interfaces differ between PRO_CEM and ILS_CEM, STEP 7 requires a full compile and complete download in CPU STOP.