Updating STEP 7 HW Config and PROFIBUS DP Drives in BRAUMAT/SISTAR V5.3 Installations

In legacy BRAUMAT/SISTAR V5.3 systems running on S7-400 CPUs, replacing obsolete PROFIBUS DP inverter drives requires strict alignment between STEP 7 HW Config and the BRAUMAT process image database. After installing the replacement drive's GSD file in HW Config, the new drive must be assigned the exact same PROFIBUS station address, identical PPO/telegram structure (PPO1-PPO5 or Standard Telegram), and identical peripheral I/O byte addresses as the legacy drive. Because BRAUMAT maps drive control and status words directly through fixed data blocks (DBs) and AREA.INI configurations, shifting I/O addresses breaks the BRAUMAT ICM driver interface. Validate drive replacement selections with an authorized Siemens distributor or the Siemens Industry Mall.

Executive Summary

BRAUMAT/SISTAR Classic V5.3 is Siemens' specialized process automation platform widely deployed in breweries and beverage plants worldwide. Maintenance engineers frequently need to replace failed, obsolete variable frequency drives (such as legacy Micromaster or third-party Danfoss drives) on active PROFIBUS DP lines with modern drives (such as SINAMICS G120). While updating hardware in standard STEP 7 is routine, BRAUMAT relies on tight coupling between peripheral I/O addresses and specialized PCU (Process Control Unit) data blocks. Incorrectly configuring the new drive causes BRAUMAT Individual Control Modules (ICMs) to lose feedback, halt recipe sequences, and generate false drive faults. This guide outlines the precise workflow to update HW Config without disrupting BRAUMAT runtime operations.

Architecture and Fundamental Mechanics

The BRAUMAT V5.3 architecture couples STEP 7 hardware configurations with specialized automation subsystems:
1. The BRAUMAT PCU and ICM Model:
In BRAUMAT, drives and valves are managed as Individual Control Modules (ICM_DRV, ICM_VALVE) running inside S7-400 PCU controllers. Unlike PCS 7 APL, which uses CFC channel driver blocks, BRAUMAT uses centralized scatter/gather communication routines that read and write fixed peripheral process image slices (PIW / PQW) mapped directly to PCU data blocks.
2. Dependency on Fixed I/O Addressing:
BRAUMAT configuration files (AREA.INI, SYSCOMP, and the hardware address table) define which peripheral address corresponds to each technological drive index. If a replacement drive in HW Config is assigned a different starting address (e.g., changing from PIW 512 to PIW 520), the BRAUMAT driver continues reading PIW 512, resulting in permanent communication timeout faults.
3. PPO and Telegram Consistency:
PROFIBUS drives communicate via Parameter-Process Data Object (PPO) types or standard telegrams (e.g., PPO 1, PPO 2, or Telegram 1 / 20 / 352). The replacement drive must be configured in HW Config with the exact same PZD (Process Data) length and word layout so that Control Word 1 (STW1) and Status Word 1 (ZSW1) align with the BRAUMAT drive block.

Step-by-Step Implementation Procedure

Document Existing Drive Configuration in HW Config:
a. Open the S7-400 station in STEP 7 HW Config.
b. Locate the legacy drive on the PROFIBUS DP line.
c. Note the exact PROFIBUS Station Address (e.g., Address 12).
d. Note the configured PPO type (e.g., PPO Type 1: 4 PKW / 2 PZD or PPO Type 3: 0 PKW / 2 PZD).
e. Note the exact input address range (e.g., PIW 512..515) and output address range (e.g., PQW 512..515).
Install New Drive GSD File:
a. Obtain the official GSD file for the replacement drive from the manufacturer.
b. In HW Config, select Options -> Install GSD File... and browse to the extracted GSD.
c. Refresh the catalog: confirm that the new drive model appears under PROFIBUS-DP -> Additional Field Devices -> Drives.
Replace the Drive Node on the PROFIBUS Line:
a. Right-click the old drive node on the PROFIBUS line and select 'Delete' (or use Replace if compatible).
b. Drag the new drive model from the catalog and drop it onto the PROFIBUS line.
c. Set the PROFIBUS address to match the original unit (e.g., Address 12).
d. Insert the matching PPO or telegram module into the drive's virtual rack slot.
e. In the module properties, manually edit the starting I/O addresses to match the exact original address range (e.g., Input 512, Output 512).
Parameterize the Physical Replacement Drive:
a. Set the physical PROFIBUS station address on the new drive using DIP switches or the operator keypad.
b. Configure drive telegram parameters to match the configured PPO structure.
c. Set motor nameplate parameters, ramp times, and fieldbus control source (p1070 = Fieldbus).
Save, Compile, and Download HW Config:
a. In HW Config, execute Station -> Save and Compile.
b. Ensure a maintenance window where the target process cell is empty.
c. Download the hardware configuration to the S7-400 CPU (PLC -> Download to Module).
d. If required by BRAUMAT V5.3, reload the PCU address tables or cycle power to restart communication buffers.

Verification

Verify that the PROFIBUS BF (Bus Fault) LED on the new drive and S7-400 CPU turns OFF.
In HW Config online test mode, open 'Module Information' for the drive: verify operational status.
From the BRAUMAT operator station, open the drive faceplate in the process overview picture.
Issue a manual start command from BRAUMAT: verify that the physical drive starts, ramps up, and feedback speed updates accurately on the screen.

Limitations and Operational Precautions

Changing the telegram layout or I/O address boundaries requires reconfiguring the BRAUMAT AREA.INI and PCU database tables; always preserve original addressing to avoid extensive database re-engineering.

Engineer FAQ

Can I replace an old Micromaster with a SINAMICS drive in Braumat V5.3?

Yes. By installing the SINAMICS GSD file and matching the original PPO type and peripheral addresses, the replacement is completely transparent to BRAUMAT.

Why is preserving the I/O address range so critical in BRAUMAT?

BRAUMAT maps drive variables directly to hardware addresses configured in internal configuration tables; changing addresses disconnects the BRAUMAT ICM software driver.

What is a PPO type in PROFIBUS drive communication?

Parameter-Process Data Object: a standardized data frame containing parameter values (PKW) and cyclic process data (PZD) such as control words and speed setpoints.