Migrating IM151-7 CPU to ET 200SP PN with Legacy ET200S Remote

Migration Overview

This procedure covers replacing a SIMATIC ET 200S CPU IM 151-7 (PROFIBUS DP master/Intelligent Slave) with a SIMATIC ET 200SP CPU 1512SP equipped with a PROFIBUS communications module (CM DP) while preserving an existing ET 200S remote-I/O island. The legacy island contains digital and analog ET 200S modules, including 6ES7 132-4HB10-0AB0 / 6ES7 132-4HB01-0AB0 (DO 4x24VDC/2A, 4HB10/4HB01) output modules that may no longer be present in the current TIA Portal hardware catalog.

Two integration paths are valid in TIA Portal:

1. HSP path: Install a Hardware Support Package that reintroduces the discontinued ET 200S articles into the hardware catalog. Use this when the modules are still catalog-supported.
2. GSD path: Install a PROFIBUS GSD file for the legacy ET 200S station (IM 151-1 / IM 151-3) and configure the station as a third-party DP slave. Use this when the IM type or module version is no longer in any catalog or HSP.

For stations based on the discontinued IM 151-1 heads, the GSD path is the only stable option because TIA Portal has removed those heads from the hardware catalog in recent versions. Both paths are documented in the SIMATIC ET 200SP system manual and the STEP 7 TIA Portal programming and operating manual.

Prerequisites

Verify module compatibility against the official TIA Portal hardware catalog and the Compatibility Tool before ordering hardware. Modules with order numbers ending in older firmware suffixes (e.g., -0AA0) may have been replaced and require an HSP to remain catalog-visible.

Architecture Before and After Migration

The legacy architecture consists of an ET 200S station that contains an IM 151-7 CPU acting as a PROFIBUS DP master with local I/O, plus a remote ET 200S island addressed over PROFIBUS. The target architecture replaces the IM 151-7 CPU with an ET 200SP PN CPU plus a CM 1542-5, and the remote island remains on the DP segment but is now reconfigured as a DP slave under the new master.

STEP 1 — Confirm TIA Portal Version Compatibility

1. Open the Compatibility Tool and select SIMATIC S7-1500 / ET 200SP as the controller family.
2. Enter the order number of the new CPU 1512SP PN and the CM 1542-5.
3. Enter the legacy IM 151-1 and module order numbers (e.g., 6ES7151-1AA05-0AB0, 6ES7132-4HB10-0AB0).
4. Note which legacy articles are supported, supported via HSP, or not supported (GSD only).

If the legacy IM appears in the catalog, jump to STEP 3. If it does not appear but is listed as "HSP-supported," continue with STEP 2. If neither applies, continue with STEP 4 (GSD route).

STEP 2 — Install Hardware Support Package (HSP)

1. Download the relevant HSPs from the Siemens HSP collection for STEP 7 / TIA Portal.
2. Extract the HSP zip and copy the .hsp file to a local directory.
3. In TIA Portal, choose Options > Support Packages > Install Support Packages.
4. Select the downloaded .hsp file and confirm the license acceptance.
5. Restart the TIA Portal when prompted; the legacy modules now appear in the hardware catalog under Distributed I/O > ET 200S.

STEP 3 — Configure the ET 200SP PN Station with PROFIBUS CM

1. Create a new project in TIA Portal and add a SIMATIC S7-1500 > CPU > CPU 1512SP PN device.
2. Open the device view and add a CM 1542-5 in slot 1 of the ET 200SP base unit.
3. In the CM properties, set Operating Mode = DP Master and assign the bus parameters: baud rate 1.5 Mbps (typical), profile DP, address 2.
4. Add the necessary ET 200SP I/O modules and a server module (6ES7193-6PA00-0AA0) in the last slot.
5. Compile the hardware configuration and download to the CPU.

Bus Parameter Table

STEP 4 — Configure Legacy ET 200S Island via GSD

1. Identify the IM 151-1 firmware version (e.g., IM 151-1 STANDARD 6ES7151-1AA05-0AB0). Locate the matching PROFIBUS GSD on the Siemens PROFIBUS GSD catalog.
2. Download the GSD file (typically SIEM80C9.GSD for IM 151-1).
3. In TIA Portal, choose Options > Manage general station description files (GSD).
4. Browse to the GSD file, select Install, and wait for completion.
5. In the network view, drag Other field devices > PROFIBUS DP > Slaves > ET 200S to the CM 1542-5 PROFIBUS subnet.
6. Assign the legacy IM a unique PROFIBUS address (e.g., 3) that does not conflict with the new ET 200SP station.
7. Open the device view of the GSD-configured station. Insert each legacy module slot in the order they appear in the physical station, using the module catalog entries that the GSD exposes (e.g., DO 4x24VDC/2A (4HB10)).
8. Match every slot — empty slots must be reserved or filled with placeholder slots to keep slot numbering aligned with the physical hardware.
9. Configure I/O addresses. ET 200S modules addressed via GSD appear under the master's I address space; document the mapping before recompiling.

STEP 5 — Address Mapping and Program Migration

The legacy IM 151-7 program used absolute addressing. When migrating to the ET 200SP CPU, every I/O bit must be re-mapped to the new address space. Recommended approach:

1. Compile the legacy project and export the symbol table as .xlsx or .sdf.
2. In the new project, create a duplicate symbol table entry for every legacy bit, with the new address (e.g., IB 100 → IB 200).
3. Open the legacy S7 program in the migrated CPU and run a global find/replace using TIA Portal cross-references.
4. Validate any direct I/O accesses (%I, %Q) in FBD/LAD/ST with the new addresses.

For programs that referenced the IM 151-7 as an I-Slave (DP slave) under a higher-level master, the transfer area configuration on the old CPU must be regenerated as a GSD transfer area on the new CM DP master. Use CPU Properties > PROFIBUS Interface > Transfer Areas in the legacy CPU export to recreate the equivalent configuration on the CM 1542-5.

STEP 6 — PROFIBUS Cabling and Termination

1. Connect the CM 1542-5 PROFIBUS port to the legacy IM 151-1 PROFIBUS connector using a PROFIBUS cable (e.g., 6XV1830-0EH10).
2. Enable termination on the connector attached to the CM 1542-5 (switch = ON).
3. Enable termination on the last physical device on the segment (typically the IM 151-1 connector).
4. Disable termination on every connector between the two end devices.
5. Verify shield grounding at both cable ends per the PROFIBUS installation guidelines.

STEP 7 — Download and Commissioning

1. Compile the TIA Portal project fully (Project > Compile all > Hardware and Software (rebuild)).
2. Connect the PG to the CPU 1512SP PN over PROFINET.
3. Download the hardware configuration first (Online > Download to device > Hardware configuration).
4. Restart the CPU to clear residual diagnostics; the CM 1542-5 should report the legacy IM 151-1 as a configured DP slave within 5–10 seconds.
5. Download the software blocks (Online > Download to device > Software (all blocks)).
6. Set the CPU to RUN. Monitor the diagnostic buffer for any SF or BF events.

STEP 8 — Verification

Field-Proven Caveats

• Module catalog visibility drift: The 4HB10 article was superseded by 4HB11 and 4HB13. If your physical modules carry a different MLFB, install the matching HSP or use the closest GSD substitute.
• GSD version vs. IM firmware: The IM 151-1 GSD must correspond to the firmware version on the physical device. Using a newer GSD than firmware can cause initialization errors during DPV0 parameterization.
• Slot consistency: Insert an empty slot placeholder for every unused slot between the IM and the last module — the GSD enforces strict slot mapping.
• Transfer area loss: If the IM 151-7 was an I-Slave on a higher-level DP master, the legacy transfer area configuration is lost during migration and must be re-derived manually.
• Server module reminder: ET 200SP stations without a server module in the last slot refuse to start and report diagnostic event W#16#0101 "Internal error."

Troubleshooting Matrix

Extended Diagnostics: Reading Diagnostic Buffer Entries

Each PROFIBUS event produces an entry in the CPU diagnostic buffer. Decode entries with the standard S7-1500/ET 200SP diagnostic manual:

Alternate Path: Use IM 151-1 as an I-Slave

If the existing ET 200S station already contains an IM 151-7 acting as an I-Slave under a higher-level DP master, retain that role. In the new architecture:

1. Configure the CM 1542-5 as a DP master.
2. Import the IM 151-1 GSD and configure it as a DP slave.
3. If the higher-level master is also being migrated, regenerate the transfer area configuration on the new master CPU using the IM 151-1 GSD-defined I/O lengths.

This avoids re-engineering the higher-level network and preserves data consistency at the boundary between the two PROFIBUS masters.

Long-Term Recommendation

Use the GSD-integration path as a transitional step only. Long-term, plan to migrate the legacy ET 200S island to ET 200SP stations. This unlocks:

• Native PROFINET diagnostics and web server on every module.
• Elimination of PROFIBUS cable infrastructure.
• Support for newer TIA Portal versions without HSP dependency.
• Channel-level diagnostics down to individual I/O points.

Reference: SIMATIC ET 200SP system manual, TIA Portal hardware catalog, Compatibility Tool.