Interface Module 6ES7151-1AA05-0AB0 6ES7 151-1AA05-0AB0 6ES7151-1AAO5-OABO

Siemens 6ES7151-1AA05-0AB0 | SIMATIC ET 200S IM 151-1 Standard — PROFIBUS DP Interface Module, RS-485, 12 Mbit/s, 244 Bytes I/O, DPV0 & DPV1, 63 Modules, 9-Pin Sub-D, Termination Module Included

Overview

The Siemens 6ES7151-1AA05-0AB0 is the IM 151-1 Standard — the PROFIBUS DP interface module that forms the head of an ET 200S distributed I/O station.

In the ET 200S station's physical assembly, the interface module is the first module on the left, followed by a power module and then the electronic I/O modules. Everything the station knows about its PROFIBUS master, its own address, and its cyclic I/O data flows through this single module.

The Standard designation distinguishes this from the High Feature (HF) variant.

Where the HF adds isochronous mode and extended DP V1 acyclic services, the Standard version covers the complete PROFIBUS DP requirement for the vast majority of distributed I/O applications: cyclic I/O exchange at up to 12 Mbit/s, DP V1 for online parameter access and diagnostics, option handling for flexible machine configurations, and direct data exchange (publisher mode) for peer-to-peer I/O data sharing between slaves.

The AA05 is the fifth hardware revision in the IM 151-1 Standard line, replacing AA00 through AA04. Each revision brought incremental improvements — the AA05 adds direct data exchange (publisher) capability and identification data access, extending the original module's functionality while maintaining complete backwards compatibility.

An AA05 physically and functionally replaces any earlier AA variant in an existing ET 200S station without configuration changes.

Key Specifications

PROFIBUS DP V0 and V1 — What Each Layer Provides

PROFIBUS DP V0 is the cyclic layer: the DP master reads output data for this slave from its output image and writes it to the ET 200S station; the station reads its current input data and sends it back to the master.

This exchange happens every bus cycle — automatically, continuously, without any explicit programme instruction. 

The I/O data appears in the master's process image input (PII) and output (PIQ) areas at addresses assigned during hardware configuration.

DP V1 extends this with acyclic services. When the ET 200S station operates in DPV1 mode under a SIMATIC S7 master, the DP master can read data records from individual ET 200S modules (DS_READ) and write parameter data to them (DS_WRITE) during live operation — without interrupting the cyclic I/O exchange.

This is the basis for online modification of analog module scaling parameters, temperature module engineering units, and any module parameter that can be updated without taking the station offline.

The maximum parameter length of 240 bytes per slot in DPV1 mode accommodates the parameter structures of even the most complex ET 200S electronic modules, including motor starters with full parameterisation and function modules with extended configuration data.

Direct Data Exchange — Publisher Mode

Direct data exchange allows this ET 200S station to publish its input data simultaneously to multiple DP masters and DP slaves on the same PROFIBUS segment.

In publisher mode, the station makes its I/O data available on the bus at a defined point in the DP master's bus cycle, and other devices (configured as subscribers) can read this data directly without routing it through the DP master's programme.

This cross-traffic capability has practical value in conveyor and transfer systems where multiple motion controllers share positional or sensor data — rather than routing all data through a central master and redistributing it, the source station publishes directly to the consumers.

The result is reduced master processing overhead and faster effective update times for the subscriber stations.

Option Handling — Flexible Station Configurations

When Option Handling is enabled in the ET 200S station's STEP 7 parameter set, the DP master tolerates module slots that are occupied by RESERVE modules instead of the configured electronic modules — without generating a diagnostic error.

This capability is used in machine designs where the same base machine hardware accommodates multiple product variants: an optional measurement module may be installed for high-end variants and replaced by a RESERVE module for basic variants, without requiring a separate hardware configuration for each variant.

Without Option Handling, the DP master checks every configured slot against the physical station at startup; any mismatch stops the station from entering RUN.

With it, the station starts normally regardless of which optional modules are present, and the programme detects the installed configuration through the status byte of each slot.

FAQ

Q1: The AA05 has been superseded by the AA06. Are they directly interchangeable in an existing station?

Yes, the AA06 is a direct hardware replacement for the AA05. Physical dimensions, mounting geometry, PROFIBUS connector, and functional behaviour are identical.

The AA06 introduced minor firmware and hardware refinements, but the change is transparent to the DP master's hardware configuration and to the STEP 7 project — no reconfiguration is needed when substituting an AA06 for a failed AA05.

Q2: How is the PROFIBUS station address set on the IM 151-1 Standard?

The PROFIBUS address is set via a rotary address selector accessible from the module's front face — typically using a small screwdriver.

The selector sets the station address from 1 to 125 in hardware.

The address must match the value assigned to this slave in the DP master's hardware configuration in STEP 7. 

A mismatch illuminates the BF LED and prevents the station from participating in the PROFIBUS bus cycle until corrected.

Q3: What is the maximum cable length between this module and the PROFIBUS DP master?

Maximum PROFIBUS cable length depends on the configured baud rate.

At 12 Mbit/s, the maximum segment length is 100m; at 1.5 Mbit/s it extends to 200m; at 187.5kbps it reaches 1,000m; at 9.6kbps the maximum is 1,200m. 

These are segment lengths — with repeaters, longer total bus runs are achievable. Standard Siemens PROFIBUS cable (6XV1830-0EH10 or equivalent) with the correct shielding and termination is required at each end of every segment.

Q4: Can the firmware on the IM 151-1 AA05 be updated, and how?

Firmware updates are performed via PROFIBUS DP using STEP 7's firmware update function. The update file (*.UPD format) is distributed by Siemens through the Industry Support portal. During the update, the DP master downloads the firmware image to the interface module over the live PROFIBUS connection; the module applies the update and restarts.

No additional hardware is required. 

Note that firmware updates for the AA05 generation may have limitations compared to the AA06, and Siemens documentation for the specific firmware version should be verified before proceeding.

Q5: What is direct data exchange (publisher), and which ET 200S module data can be published?

In publisher mode, the IM 151-1 AA05 places its input data onto the PROFIBUS bus at a defined slot in the DP cycle, independently from the normal master-slave exchange.

Other DP slaves on the same segment — configured as subscribers — read this data directly. 

The published data is the complete 244-byte input area of the ET 200S station.

Any data that appears in the station's process input image — digital inputs, analog measurements, motor starter feedback — is included in the published data and available to subscribers without master programme involvement.