Resolving Unidentified PROFIBUS PA Field Devices in SIMATIC PDM Lifelist via Device Integration Manager

In SIMATIC PDM (Process Device Manager V8.1 and V8.2), when PROFIBUS PA field instruments (such as an Endress+Hauser Promag 50H electromagnetic flowmeter or a Siemens SITRANS TH400 temperature transmitter connected behind an FDC 157 DP/PA Coupler or DP/PA Link) appear with red crossmarks ('X') or 'Cannot define device' in the PDM Lifelist, the root cause is missing Electronic Device Description (EDD) files in the local PDM Device Catalog. The Lifelist scan interrogates the device's PROFIBUS identification number (Ident Number), but PDM cannot bind the device without the corresponding manufacturer EDD installed via the SIMATIC PDM Device Integration Manager (DIM). To resolve this, engineers must download the exact EDD package from the device manufacturer or Siemens Industry Online Support, import it using DIM, update the PDM catalog, and assign the device type.

Architecture of SIMATIC PDM Fieldbus Scanning and Lifelist

SIMATIC PDM is the universal, vendor-neutral engineering tool in SIMATIC PCS 7 used to configure, parameterize, calibrate, and diagnose intelligent field devices (HART, PROFIBUS DP, PROFIBUS PA, and PROFINET). When commissioning a fieldbus segment, engineers utilize the Lifelist utility.

The Lifelist scans physical bus addresses (0 to 126), establishes direct Layer 2 communication, and retrieves the device's electronic identifier (Manufacturer ID and Device Revision). For PROFIBUS PA devices connected via an active DP/PA Link (IM 153-2) or FDC 157 coupler, the PDM communication manager routes requests through the AS controller's CP card or a local USB/CP 5711 communication processor into the lower-speed (31.25 kbit/s) PA segment.

Root Cause Analysis: Why Devices Display Red Crossmarks

A field instrument displaying a red 'X' in the Lifelist indicates that while physical electrical communication exists, semantic parameterization is blocked:

Missing EDD File: The SIMATIC PDM Device Catalog does not contain the Electronic Device Description corresponding to the device's Profile or Manufacturer ID.
Partial Catalog Installation: Users often install the generic Siemens PDM Device Library DVD (pdmdevices_cd...zip) assuming it contains all third-party files. However, specialized third-party instruments (such as Endress+Hauser Promag 50H or Emerson Rosemount transmitters) require proprietary EDDs downloaded directly from the OEM portal.
Ident Number Mode Mismatch: Many PA devices support two operating modes: Standard Profile mode (e.g., Profile 3.0 Ident Number 0x9740 for flow) and Manufacturer-Specific mode (e.g., E+H specific Ident Number). If the device hardware is set to manufacturer mode but PDM only has the generic profile EDD, identification fails.

Importing EDD Device Descriptions via Device Integration Manager

To integrate the required device descriptions into SIMATIC PDM:

Obtain EDD Packages: Download the device-specific EDD zip archive from the manufacturer (e.g., Endress+Hauser portal for Promag 50H or Siemens SIOS for SITRANS TH400).
Launch Device Integration Manager (DIM): Close SIMATIC Manager and PDM. Click Start > Siemens Automation > SIMATIC > SIMATIC PDM > Device Integration Manager.
Scan Source Path: In DIM, select Source > Search Path... and browse to the extracted folder containing the .edd and .info files.
Compile Catalog: Select the detected devices, click Integrate, and confirm the license acceptance prompts. DIM compiles the descriptions into the central PDM device repository.
Update Catalog in PDM: Open PDM (or SIMATIC Manager), navigate to Options > SIMATIC PDM > Update Device Catalog.

Configuring DP/PA Links and Couplers in HW Config and PDM

To establish proper online routing from the ES to the PA field instruments:

HW Config Architecture: Ensure the DP/PA Link (IM 153-2 6ES7153-2BA10-0XB0 or 6ES7153-2BA70-0XB0) is configured on the PROFIBUS DP master line. Behind the IM 153-2, place the FDC 157 coupler (6ES7157-0AC85-0XA0) or standard coupler.
Assign Slot Modules: In HW Config, insert the specific instrument module (e.g., E+H Promag 50H or PA Profile Analog Input) under the PA master line with matching DP addresses.
PDM Network View: In SIMATIC Manager Process Device Network View, open the DP/PA Link object; verify that both the Promag 50H and SITRANS TH400 are visible with assigned PA addresses matching physical field dip-switches.

Comparison of PDM Device Integration Profiles (Standard vs EDD)

The following table compares the capabilities of generic PROFIBUS PA profile drivers versus dedicated manufacturer EDD files in SIMATIC PDM:

| Diagnostic Feature | Generic PA Profile 3.0 Driver | Manufacturer-Specific EDD File |
|---|---|---|---|
| Primary Process Value (PV) | Available (Standard floating point + QC) | Available (Standard floating point + QC) |
| Totalizer / Secondary Variables | Limited access | Full access (Mass flow, temperature, volume) |
| Advanced Diagnostics | Generic NAMUR NE 107 flags | Detailed error logs, sensor coil integrity, electrode health |
| Calibration and Zero-Trim | Not supported | Full interactive calibration wizard |
| PDM Lifelist Identification | Identifies as generic device | Exact model, firmware, and serial displayed |
| Firmware Upgrade via Bus | Not supported | Supported if vendor provides binary package |

Verification

Verify field device identification in SIMATIC PDM:
1. In SIMATIC Manager Process Device Network View, right-click the PROFIBUS DP network and select Start LifeList.
2. Execute the scan; confirm that the Promag 50H and SITRANS TH400 appear with green checkmarks and exact device model names.
3. Double-click the Promag 50H in the device list; verify that SIMATIC PDM opens the online parameter view without 'Device description missing' dialogs.
4. Navigate to the Diagnosis tab in PDM; confirm that live measurement values and device status registers update cyclically.

Limitations and Operational Precautions

Never download parameters to a field instrument while the process unit is actively operating in automatic control, as writing configuration records can cause analog outputs to freeze or enter fail-safe states. Always verify whether the physical instrument's write-protection jumper or software lock is enabled before attempting to write calibration parameters from PDM. When using DP/PA Couplers in stand-alone mode (without an IM 153-2 Link), PDM communication is limited to 45.45 kbit/s or requires specialized DP/PA communication processors.

Engineer FAQ

Where can I find EDD files for third-party devices?

Third-party EDD files must be downloaded from the respective equipment vendor's website (e.g., Endress+Hauser, Emerson, ABB) or from the FieldComm Group portal. Siemens only supplies Siemens device EDDs and standard profile drivers on the PDM DVD.

Why does the Lifelist find the device address but fail to communicate?

This occurs when the physical baud rate on the bus does not match the coupler configuration or when the device's configured Ident Number in HW Config differs from the operating mode configured in the physical instrument.

What is the difference between an EDD and a GSD file?

A GSD file is used by Step 7 HW Config to configure cyclic I/O data exchange and process image sizes. An EDD (Electronic Device Description) is used by SIMATIC PDM for acyclic parameterization, detailed calibration, and diagnostics.