Adding the ET 200SP DI 16x24VDC BA Module (6ES7131-6BH01-0BA0) to an Existing IM 155-6 PN ST Station Under TIA Portal V14

This reference documents the procedure for integrating a SIMATIC ET 200SP digital input module with order number 6ES7 131-6BH01-0BA0 (DI 16x24VDC BA) into an existing distributed I/O station that is already equipped with the interface module 6ES7 155-6AR00-0AN0 (IM 155-6 PN ST) and a 6ES7 131-6BH00-0BA0 (DI 16x24VDC HF) module. The project is currently maintained in TIA Portal V14, while the newer BA module only appears in the V15.1 hardware catalog. The technical answer to the underlying question is that the BA module can be placed in the same station as the HF module, but the BA variant has to be added as a GSDML-based device in TIA Portal V14, because the HSP that introduced it is not part of the V14 default catalog.

1. ET 200SP Architecture and Where the Question Sits

The SIMATIC ET 200SP is a finely scalable, modular distributed I/O system from Siemens, designed for high-density panels (roughly 50% narrower than ET 200S) and a wide range of digital, analog, fail-safe, motor starter, and technology modules. The system is described in detail on the official SIMATIC ET 200SP product page and in the Siemens catalog:

• SIMATIC ET 200SP - The Scalable Periphery System
• SIMATIC ET 200SP Catalog and Product Overview (PDF)

An ET 200SP station consists of three mechanical / logical layers:

1. Interface module (IM) or CPU - The PROFINET / PROFIBUS head-end that handles IO controller / IO device communication. The IM 155-6 PN family is the most common PROFINET head for ET 200SP. The IM 155-6 PN ST is a "Standard" performance class that supports PROFINET IO RT, IRT, and PROFIenergy.
2. BaseUnits (BU) - The terminal blocks on the DIN rail that carry the backplane and field wiring. Each slot in an ET 200SP station is always a BaseUnit, with the I/O module plugged onto it. BU types are color-coded (e.g. BU15-P16+A0+2D, BU15-P16+A0+2B) and a slot also requires a BU of the correct type for the I/O module family.
3. I/O modules - The actual DI / DO / AI / AO / F-DI / F-DO / technology / motor modules that plug into the BaseUnits. Module width is typically 15 mm (one slot).

Up to 32 I/O modules can be plugged behind an IM 155-6 PN ST (16 modules per slot group, two groups of BaseUnits; for a CPU variant the limit is higher, up to 65 modules when the ET 200SP runs with its own CPU that then addresses S7-1500 I/O, per the TIA Portal help at ET 200SP with its own CPU module).

The question at hand is a typical real-world scenario: an existing ET 200SP station is full at slot N-1, a new field device is wired back to a free 24 V DC sink, and the only spare DI module in the cabinet is a 6ES7 131-6BH01-0BA0, which the engineer cannot find in the V14 hardware catalog. There are two parts to the answer: (a) the module is mechanically and electrically compatible, and (b) it can be added to the V14 project by installing the matching GSDML file.

2. Identifying the Hardware: Order Numbers, MLFB Structure, and Functional Class

Siemens SIMATIC module order numbers are encoded in a structured MLFB. Decoding the three numbers used in the station clarifies what each module is and what feature class it belongs to.

Decoding the two DI modules shows that they share the same functional channel count and signal polarity, and differ only in the trailing digits:

• 6ES7 131-6BH00-0BA0 - "6BH00" identifies the high-feature 16-input 24 V DC variant. "HF" stands for "High Feature" and is the designation used in the Siemens module faceplate. The HF module is documented in the SIMATIC ET 200SP digital input modules datasheet and supports per-channel wire-break / short-circuit diagnostics, value status (Quality Information), and isochronous mode on capable head modules.
• 6ES7 131-6BH01-0BA0 - "6BH01" identifies the Basic 16-input 24 V DC variant. The BA module has identical pin-out and slot footprint to the HF module but a reduced feature set, optimized for cost-sensitive applications that do not need per-channel diagnostics, value status, or isochronous mode.

Both modules use the same BaseUnit family (BU type A0 / light-colored BaseUnit, suitable for 24 V DC inputs). The module front connectors are the same push-in or screw-type terminal blocks used by the HF module. See the module family overview on Mouser: Siemens SIMATIC ET200SP I/O Modules.

3. Hardware Compatibility: Mixing HF and BA Modules in One Station

The ET 200SP system allows heterogeneous mixing of I/O modules in a single station, as long as the BaseUnit types match and the total count stays within the head-end limit. Mixing a 6BH00 HF with a 6BH01 BA in the same station is fully supported. The IM 155-6 PN ST handles each module as an independent PROFINET slot; the value status of the BA module simply stays at "good" (or is not mapped) and the slot-level diagnostics are reported by the head-end only for the events that the BA module can actually generate.

There is no requirement that all DI modules in a station belong to the same feature class. Common mixed configurations include HF modules for high-priority sensor feedback (with diagnostics) and BA modules for non-critical auxiliary signals (e.g. cabinet door switches, contactor auxiliary contacts). The slot index and the I/O address range in the PROFINET frame are unique per module, so the application program can address the HF and BA modules independently.

4. Feature Comparison: DI 16x24VDC HF (6BH00) vs BA (6BH01)

Although the channel count, polarity, and rated voltage are identical, the HF and BA variants have very different on-module intelligence. The table below summarizes the most commonly used selection criteria.

The two consequences of choosing a BA module are the loss of per-channel diagnostics and the absence of value status. From a control program perspective, the BA module behaves like a "flat" 16-bit input image: bit 0 = channel 0, bit 15 = channel 15, no per-bit quality. Programs that rely on value status (for example to switch over a redundant sensor or to flag a degraded measurement) will see value status as always-valid on BA slots, which is acceptable for plain digital status bits but unsuitable for any signal that is to be treated as "good / bad".

5. TIA Portal Catalog vs GSDML-Based Configuration

Every TIA Portal version ships with a hardware catalog that contains the modules and head-ends released at the time that TIA Portal's Hardware Support Package (HSP) was frozen. When a new module is added to the catalog after a TIA Portal version is released, it normally appears:

• in the next TIA Portal release (for example, the 6BH01 first appears in the V15.1 catalog, as the engineer observed);
• as part of an HSP for an already-released TIA Portal version, downloadable from Siemens Industry Online Support;
• as a GSDML file that can be installed in any TIA Portal version that supports PROFINET GSDML devices (V14 and later, including V13 SP2 with limitations).

For the V14 project described in the question, the practical approach is the third option: install the GSDML for the ET 200SP family (or the specific GSDML that lists 6BH01) on the maintenance laptop, then add the module as a PROFINET device / GSD-based I/O module behind the IM 155-6 PN ST. The same approach works for the office machine.

The reason for using a GSDML-based device rather than a HSP is that an HSP is tied to a specific TIA Portal major version. If the maintenance team is permanently on V14 and the company is not ready to upgrade, an HSP upgrade on V14 is also possible, but in many plants the GSDML route is the smallest, most reversible change. Siemens describes the general flow in the TIA Portal help on "Installing PROFINET GSD files" and the corresponding GSDML download page (see the next section).

6. Locating the Correct GSDML File on Siemens Support

The PROFINET GSD files for SIMATIC ET 200SP are published on Siemens Industry Online Support. The article is searchable by the term "ET 200SP GSD" or by article ID. The download page is at:

• SIMATIC ET 200SP PROFINET GSD files (Siemens Support, article ID 109750254)

Each release of the GSDML package corresponds to a specific PROFINET GSDML schema version. The file name follows the PROFINET naming convention:

GSDML-V<GSDML version>-<date yyyymmdd>-Siemens-ET200SP.xml

Typical examples found in the support download package:

GSDML-V2.31-20131106-Siemens-ET200SP.xml
GSDML-V2.32-20140113-Siemens-ET200SP.xml
GSDML-V2.33-20150629-Siemens-ET200SP.xml
GSDML-V2.34-20181112-Siemens-ET200SP.xml

For TIA Portal V14 (which uses the PROFINET GSDML schema 2.31 / 2.32 / 2.33 layer), GSDML-V2.3x files are imported without schema conversion. TIA Portal will refuse to import a GSDML with a schema version it does not support, so always pick the newest GSDML whose schema is still compatible with V14. The newest GSDML in the package is normally safe to import - it is backward compatible in terms of module definitions.

The download package also contains readme files, device description texts, and, in some packages, a sample project. Unzip the package to a local folder before installing.

7. Installing the GSDML in TIA Portal V14 (Step-by-Step)

1. Open TIA Portal V14 on the maintenance laptop.
2. Open the station project (or just leave the portal open; the GSDML import is global, not project-bound).
3. From the Options menu, choose Manage general station description files (GSD).
4. In the "Source path" field, browse to the folder that contains the unzipped GSDML .xml file(s).
5. Select the GSDML that lists the 6ES7 131-6BH01-0BA0 module (the module appears in the right-hand list of Devices as "DI 16x24VDC BA" under the ET 200SP sub-folder).
6. Click Install. Wait until the status text confirms successful installation. TIA Portal closes and reopens the device catalog in the background.
7. Close the GSD management dialog. The GSDML device is now available under Devices & Networks > Other field devices > PROFINET IO > ET 200SP in the hardware catalog.

If multiple GSDML files are installed, the newest one is shown at the top of the catalog tree; older ones remain as a fall-back. Removing a GSDML is done from the same dialog. Note that TIA Portal requires the project to be closed for some GSDML operations if the file is part of an active device configuration.

8. Adding the 6BH01 Module to the Device Configuration

Once the GSDML is installed, the new module can be added to the ET 200SP station. The exact path depends on whether the station is configured as an IO device of an S7-1200 / S7-1500 or whether it is configured behind its own CPU.

1. Open the project that contains the existing IM 155-6 PN ST (6ES7 155-6AR00-0AN0).
2. In the project tree, expand Devices & Networks and double-click the ET 200SP station.
3. Open the Device view of the IM 155-6 PN ST. The current modules are shown in the slot table.
4. Identify the first free slot. The free slot must be physically equipped with a BaseUnit of type A0; if not, the slot is marked as "not occupied" and the new module will be flagged as a configuration error during compile.
5. In the hardware catalog, navigate to Other field devices > PROFINET IO > ET 200SP > DI > DI 16x24VDC BA (6ES7 131-6BH01-0BA0). Drag and drop it onto the free slot.
6. If TIA Portal asks for a submodule / channel configuration, accept the default (16 DI, no diagnostics) for the BA module.
7. Compile (rebuild) the project. The compile result should show no new errors related to the new slot.
8. Download the configuration to the IO controller (S7-1200 or S7-1500). The IM 155-6 PN ST is re-parameterized; the new slot is enabled and the BA module starts reporting cyclic input data.

For GSD-based I/O modules, the slot can also be added directly to the IM by right-clicking the IM in the network view, choosing Properties > Device configuration, and then dragging the module from the catalog. The catalog tree entry for the GSD-based 6BH01 is the same as for HSP-based modules, but the icon is flagged with a small GSD overlay.

9. Parameter Assignment and I/O Address Mapping

The DI 16x24VDC BA module exposes one input word of process data (16 bits, 2 bytes). TIA Portal assigns the I/O addresses automatically when the module is dropped into the slot, but the addresses can be overridden in the module's properties dialog. For mixed HF/BA stations, address planning is the main area to watch.

The HF module's input area in the PROFINET frame is 2 bytes of process data plus 1 byte for the value status (QI). The BA module's input area is 2 bytes of process data only. The total input payload in the PROFINET cyclic frame therefore grows by 2 bytes per BA module (no QI byte) and by 3 bytes per HF module (process data + QI). For an S7-1200 / S7-1500 IO controller, this is well within the limits of the device, but for very small IO controllers (e.g. S7-1200 CPU 1211 / 1212) the maximum number of I/O modules per PROFINET device is still bounded by the controller's process-image size and the field-device count. The IM 155-6 PN ST supports up to 32 I/O modules per station in the Standard performance class and up to 64 modules in the High Feature (HF) performance class.

The BA module's parameter dialog is intentionally short. The user-configurable options are limited to:

• Input delay (where the BA module offers a choice between a small set of fixed values, typically one or two options for fast / standard sensors);
• Channel-granular enable / disable (each of the 16 inputs can be turned off individually to suppress noise on unused channels);
• Module-level behavior on loss of PROFINET connection (substitute value behavior, but for digital inputs "substitute value" is a per-channel 0/1 setpoint rather than a hold-last-value).

No per-channel diagnostics are exposed. The PROFINET alarm "Channel diagnosis" is therefore not generated by the BA module, which is one of the reasons Siemens recommends the HF module for safety-relevant or diagnostic-relevant feedback.

10. Commissioning, Online Diagnostics, and Verification

After downloading the new configuration, the following checks confirm that the BA module is correctly integrated.

1. Topology check: in TIA Portal, open Online & Diagnostics for the IM 155-6 PN ST. The "Module status" tab should show all configured modules as OK. The new BA slot is listed with its order number and module name.
2. Process data check: in the IM 155-6 PN ST's IO tags view (or the project tags for the PROFINET device), force the inputs of the new module one by one and watch the I-address area move. The PLC tag table should show the correct bit changes.
3. PROFINET frame check: in the PROFINET diagnostics of the IO controller, confirm that the cyclic frame length has grown by 2 bytes (BA module payload). If the frame is unchanged, the slot is not being included in the cyclic data exchange; the most common cause is a mismatch between the configured slot and the physically populated BaseUnit.
4. Diagnostic buffer: read the diagnostic buffer of the S7-1200 / S7-1500 CPU. There should be no "station failure", "module failure", or "submodule mismatch" entries for the ET 200SP station. Any error message that points to the new slot is almost always a slot indexing or BaseUnit-type problem, not a BA/HF compatibility problem.
5. Wire-break / short-circuit: deliberately induce a wire break on one of the BA channels. The HF module would raise a per-channel diagnostic alarm and the value status bit would clear; the BA module will simply report the input as 0 (or hold last valid state) without raising a diagnostic alarm. Confirm that the application handles the BA module's "no value status" behaviour correctly.

11. Multi-Version TIA Strategy: V13, V14, and V15.1 on the Same Site

The maintenance laptop situation described in the source question is common in mid-sized plants: the office has the latest TIA Portal, the maintenance team is one or two versions behind, and updates are not approved because they would require retesting programs on every station. A few practical guidelines help in this mixed environment.

• TIA Portal V14 and V15.1 can coexist on different machines; projects saved in V14 can be opened in V15.1 (with a one-way upgrade prompt) but cannot be saved back as V14. The maintenance laptop's projects must stay in V14.
• GSDML files are cross-version: a GSDML installed in V14 is also available in V15.1 (and vice versa) because the catalog files are read from the user profile. The GSDML that lists 6BH01 in V15.1 can be back-ported to V14, but the GSDML file's PROFINET schema must be supported by V14.
• HSPs are version-bound: an HSP installed under V15.1 is invisible to V14. The maintenance laptop must install a V14-compatible HSP if the GSDML route is not used.
• Project format: V14 and V15.1 use different binary project formats. The same physical station can have two project files, one per TIA Portal version, but they cannot be merged. A common practice is to keep the V14 project as the production baseline and a parallel V15.1 project for the office engineers.
• Firmware: when the IM 155-6 PN ST firmware is updated on the head-end, both projects must be updated to match. The recommended practice is to align the office and maintenance projects to the same PROFINET device name and IP address plan, so the firmware update is the only variable.

For the V14 maintenance laptop, the steps in section 7 of this document are sufficient: install the GSDML, add the BA module to the slot, compile, and download. The office laptop, which already has V15.1, will display the same module out of the catalog and can re-validate the program at leisure.

12. Design and Migration Notes for Future Expansion

The decision to use a BA module in a station that started as an all-HF station is sometimes forced by stock availability. A few design notes help to keep future expansions clean:

• Reserve at least one HF slot for diagnostics. If the station grows further, having a spare HF module for "important" signals is far easier than migrating BA to HF later.
• Keep a paper inventory of the IM 155-6 PN ST firmware version. The IM 155-6 PN ST has gone through several firmware revisions (e.g. V1.0, V1.1, V2.0, V3.0, V4.0, V4.2 for newer revisions). Newer modules can require a minimum head-end firmware; an old IM might not accept a newer BA module if the firmware matrix says so.
• Document the GSDML version used in the project. The TIA Portal Project tree > Common data > GSD files view shows the GSDML files that are referenced by the project. Pin the version in the project readme so that the next engineer does not have to guess which GSDML is currently installed.
• Use Type / Instance concept: in V14 and later, both HF and BA DI modules can be configured as type / instance. This makes it easier to add additional stations with the same module mix without re-entering the parameters.

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