Siemens 6ES7155-6AU01-0BN0 — ET 200SP PROFINET Module Buyer Review

By Abdullah Zahid
13 min read
Siemens 6ES7155-6AU01-0BN0 PROFINET Interface Module IM 155-6PN Standard for SIMATIC ET 200SP distributed I/O rack

Siemens 6ES7155-6AU01-0BN0 PROFINET Interface Module IM 155-6PN Standard — Complete Specs, Applications, and Selection Guide

Controls engineers specifying distributed I/O for PROFINET-based systems frequently arrive at the Siemens 6ES7155-6AU01-0BN0 after confirming they need a high-density, hot-swappable interface module within the SIMATIC ET 200SP architecture. This module — officially the SIMATIC ET 200SP, PROFINET Interface Module IM 155-6PN Standard — supports up to 32 I/O modules and 16 ET 200AL modules per station, communicates at 100 Mbps full-duplex over a 2-port RJ45 switch, and runs on a 24 V DC supply with built-in reverse polarity and short-circuit protection. Whether you are commissioning a new assembly line or replacing an aging interface card, the specification details below will confirm whether this is the correct part for your system.

If you have already confirmed this is the right part, check current pricing and availability at LeadTime.ca — ships worldwide.

Who Should Buy the 6ES7155-6AU01-0BN0 — and Who Shouldn't

The Siemens 6ES7155-6AU01-0BN0 is the right choice for engineers deploying modular distributed I/O over a PROFINET network where station density and PROFIsafe capability are both required. Confirm all of the following before ordering:

  • Your controller supports PROFINET as the communication standard — this module does not support PROFIBUS or other fieldbus protocols
  • Your application fits the SIMATIC ET 200SP architecture specifically — ET 200M, ET 200S, and other ET 200 families use different interface modules
  • Your station requires up to 32 standard I/O modules plus up to 16 ET 200AL modules — stations requiring fewer modules may be better served by a lower-cost variant
  • Your power supply delivers 24 V DC within the 19.2 V to 28.8 V range and can sustain a maximum of 550 mA steady-state plus a 3.7 A inrush at startup
  • Your configuration toolchain runs STEP 7 TIA Portal V14 or later, or STEP 7 V5.5 SP4 or later for legacy projects
  • Your network topology supports a 2-port RJ45 Ethernet switch configuration with autonegotiation at 100 Mbps

If isochronous real-time mode is mandatory for synchronized motion control, or if you need more than 2 IO Controllers sharing the same I/O station, this module is not the correct fit — review the 6ES7155-6HB02-0AB0 (IM 155-6PN HF) for higher real-time determinism, or consult the variant comparison table further below.

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What the 6ES7155-6AU01-0BN0 Actually Does in a Live System

The Siemens 6ES7155-6AU01-0BN0 is not a standalone controller. It is a PROFINET gateway and interface module — the communication hub that connects a modular rack of SIMATIC ET 200SP I/O modules to a PROFINET-capable PLC or controller. Every digital input card, analog output card, and safety module in the ET 200SP station depends on this interface module to exchange data with the central controller over the PROFINET network.

Within a single station, the 6ES7155-6AU01-0BN0 manages up to 256 submodules distributed across 32 standard I/O modules and 16 ET 200AL modules. The integrated 2-port RJ45 switch allows the module to participate in a PROFINET line or ring topology without requiring an external unmanaged switch at every node. PROFIsafe and PROFIenergy protocol support means the same interface module handles safety-rated emergency stop circuits and power consumption monitoring without additional communication hardware. The module ships with an included server module (6ES7193-6PA00-0AA0), which occupies the right-hand termination slot of the ET 200SP rack.

Hot-swap support for individual I/O modules is a practical operational feature: a technician can remove and reinsert a single I/O module while the interface module remains powered and the controller continues running — a meaningful capability in high-availability production environments where planned downtime is unacceptable.

Typical System Architecture: Where This Module Sits in the Signal Chain

The 6ES7155-6AU01-0BN0 occupies the interface layer between the PROFINET controller and the physical I/O devices mounted in the ET 200SP base frame. It is never the first or last device in the network — it is always the bridge between them.

  • Central PLC or controller (SIMATIC S7-1500, S7-300, or equivalent PROFINET IO Controller) originates all process commands and receives I/O data over the PROFINET network
  • PROFINET network (100BASE-TX, Category 5e or higher cabling) carries cyclic I/O data and acyclic diagnostic frames to and from the interface module via RJ45 ports on the BusAdapter
  • 6ES7155-6AU01-0BN0 receives network frames, coordinates I/O module data exchange, and manages station-level diagnostics including LED status indication
  • ET 200SP I/O modules (digital inputs, digital outputs, analog inputs, analog outputs, safety modules) mount directly onto the base units in the rack and communicate with the interface module via the internal backplane
  • Field devices — sensors, actuators, motor drives, valve terminals — connect directly to the I/O module terminals at the field wiring level

Industries and Applications Where This Module Is Specified

Automotive assembly lines are a primary application. Distributed sensor arrays and pneumatic actuator outputs across multiple work stations are each served by an ET 200SP station with the 6ES7155-6AU01-0BN0 at its head. The 32-module capacity allows a single station to aggregate enough I/O to serve an entire assembly cell without running individual home-run cables back to the main panel.

Food and beverage bottling machinery frequently specifies this interface module for its wide operating temperature range — up to 60°C in horizontal installation — and for PROFIenergy support, which enables centralized energy consumption monitoring across all distributed I/O nodes in a production facility.

Safety-critical applications in packaging and pharmaceutical manufacturing use the PROFIsafe capability to integrate emergency stop circuits and light curtain inputs directly into the ET 200SP station without separate safety relay modules or a second safety fieldbus.

Material handling conveyor systems and high-availability process lines specify the hot-swap capability specifically. When a field I/O module fails, a technician can replace it without powering down the station, eliminating an unplanned production stop that could cost far more than the module itself.

Application Typical Deployment
Automotive assembly line Distributed ET 200SP stations per work cell; 20–32 I/O modules per station aggregating sensor and pneumatic actuator signals
Food and beverage bottling Single interface module per production zone; PROFIenergy enabled for power monitoring; 60°C ambient tolerance for oven or wash-down adjacent areas
Safety-critical machinery PROFIsafe-enabled ET 200SP station integrating emergency stop, light curtain, and safety door inputs without separate safety fieldbus
Material handling conveyors Hot-swappable I/O modules on active conveyor lines; module replacement during operation with zero controller downtime
Chemical batch processing Distributed analog I/O for temperature, pressure, and flow transmitters; configuration control via dataset for recipe-driven processes
OEM machine builder Compact rack with 20+ mixed I/O channels replacing multiple discrete I/O blocks; native STEP 7 TIA Portal integration reducing panel design time

Purchase-Decision Specifications at a Glance

Parameter Value
Rated Supply Voltage 24 V DC (range: 19.2 V to 28.8 V DC)
Maximum Current Consumption 550 mA (rated: 450 mA); inrush max 3.7 A
Maximum Standard I/O Modules per Station 32
Maximum ET 200AL Modules per Station 16
Maximum Submodules per Station 256
PROFINET Interface 100 Mbps full-duplex (100BASE-TX), 2-port RJ45 switch with autonegotiation and autocrossing
Protocol Support PROFINET IO, PROFIsafe, PROFIenergy, PROFIBUS
IRT Frame Times 250 µs to 4 ms in 125 µs increments
Operating Temperature 0°C to 60°C (horizontal); 0°C to 50°C (vertical); max altitude 5,000 m
Dimensions (W × H × D) 50 mm × 117 mm × 74 mm; weight 147 g (without BusAdapter)

Full technical specifications are available on the product page at LeadTime.ca.

6ES7155-6AU01-0BN0 vs. IM 155-4PN ST vs. IM 155-6PN HF: Which One Do You Actually Need?

Specification 6ES7155-6AU01-0BN0 (IM 155-6PN ST) 6ES7155-4BA02-0AB0 (IM 155-4PN ST) 6ES7155-6HB02-0AB0 (IM 155-6PN HF)
Max Standard I/O Modules 32 16 32
Max ET 200AL Modules 16 8 16
Max Submodules per Station 256 128 256
PROFINET Standard 100 Mbps full duplex 100 Mbps full duplex 100 Mbps full duplex (IRT optimized)
IRT Real-Time Capability 250 µs to 4 ms 250 µs to 4 ms Deterministic, lower jitter
PROFIsafe Support Yes Yes Yes
Hot Swapping Yes, single Yes, single Yes, single
Price Relative to This Module Baseline 20–30% lower 30–50% higher
Best Use Case Standard modular I/O; cost-effective high-density Smaller distributed systems; cost-sensitive builds High real-time determinism; synchronized motion control

If your architecture demands full 32-module density with PROFIsafe at a baseline cost, the 6ES7155-6AU01-0BN0 is the correct choice — check current availability at LeadTime.ca.

Expert Verdict: Honest Assessment for Engineers Evaluating This Part

The Siemens 6ES7155-6AU01-0BN0 earns its place as the workhorse interface module in the SIMATIC ET 200SP family. The combination of 32-module capacity, 256 submodule support, PROFIsafe, PROFIenergy, and hot-swap capability in a 50 mm wide housing addresses the majority of distributed I/O requirements in discrete and process manufacturing without requiring a premium module. The integrated 2-port switch eliminates the need for external Ethernet switches at each station, which reduces panel real estate and wiring cost on multi-drop PROFINET lines. The included server module (6ES7193-6PA00-0AA0) and native STEP 7 TIA Portal V14 integration mean that a controls engineer familiar with the SIMATIC ecosystem can have a station configured and communicating in a single session.

The honest limitations are worth stating plainly. This module does not support isochronous mode for synchronized multi-axis motion control — if your machine requires true isochronous real-time (IRT) with the deterministic jitter performance that servo drive synchronization demands, you need the 6ES7155-6HB02-0AB0 (IM 155-6PN HF) and should budget 30–50% more accordingly. The shared device support caps at 2 IO Controllers, which limits use cases involving redundant or multi-controller architectures. And while the 3.7 A inrush current at startup is normal for this class of module, specifying a power supply without adequate headroom is a common commissioning mistake that trips upstream protection devices — something to size for explicitly.

From a procurement standpoint, new units typically carry lead times of 4 to 8 weeks through standard channels, with express sourcing available at a 10–15% premium. Volume orders of 5 or more units typically qualify for pricing breaks. Remanufactured units are available at 40–75% of new list price from verified industrial parts suppliers offering 2-year warranties, which makes this module an attractive candidate for MRO spares programs or cost-sensitive OEM builds. If your application requires current firmware (V4.2) and you are sourcing remanufactured units, verify the firmware version before acceptance. If this matches your system requirements, view current stock and pricing at LeadTime.ca.

For volume pricing or to confirm lead time before committing to a build, contact the LeadTime.ca team directly — we ship worldwide.

Wiring and Installation: What to Verify Before You Commission

  • Confirm your 24 V DC supply is regulation-capable, sized for a sustained 550 mA draw plus downstream I/O module current, and can absorb a 3.7 A inrush at module startup without tripping upstream protection — reverse polarity protection is built into the module, so no external series diode is needed on the supply rail
  • Connect PROFINET cables (Category 5e or higher) to the 2-port RJ45 ports on the BusAdapter; autonegotiation and autocrossing are both enabled, so crossover cables are not required and cable polarity at the RJ45 is handled automatically
  • Keep PROFINET cabling physically separated from 24 V switching load cables and AC power conductors to avoid electromagnetic interference that can cause intermittent LINK TX/RX faults
  • Insert I/O modules into the ET 200SP base units until each module clicks and seats fully — mechanical keying prevents reverse insertion, and the GSD configuration in STEP 7 will validate the module type on the first download
  • Verify installation orientation before mounting: horizontal installations support operation up to 60°C ambient, while vertical installations limit maximum ambient temperature to 50°C — confirm your panel thermal environment matches the selected orientation

Compatible Modules and System Expansion Within SIMATIC ET 200SP

The 6ES7155-6AU01-0BN0 is the interface head for the SIMATIC ET 200SP modular I/O ecosystem. The following modules and accessories are directly compatible within the same station:

  • 6ES7193-6PA00-0AA0 — Server module included with the interface module; occupies the right-hand termination position of the ET 200SP rack and is required for station completion
  • SIMATIC ET 200SP I/O modules — Digital input, digital output, analog input, analog output, and technology modules that mount onto ET 200SP base units; up to 32 standard modules per station
  • SIMATIC ET 200AL modules — Compact distributed I/O modules connectable via ET-Connection from the ET 200SP station; up to 16 per station supported by this interface module
  • ET 200SP BusAdapter (BA 2xRJ45 or equivalent) — Required accessory providing the physical RJ45 PROFINET ports; the 2-port switch configuration enabling line and ring topologies is delivered through the BusAdapter, not the base module body
  • F-modules (PROFIsafe-rated I/O modules) — Safety input and safety output modules that integrate directly into the ET 200SP rack and are coordinated by the interface module using the PROFIsafe protocol stack supported by the 6ES7155-6AU01-0BN0

Wrong-Part Prevention Checklist Before You Order

Run through every item below before submitting an order or RFQ for the Siemens 6ES7155-6AU01-0BN0 — these are the most common causes of wrong-part returns and commissioning delays:

  1. Confirm your controller or PLC supports PROFINET as the communication standard (not PROFIBUS or other protocols)
  2. Verify the application requires ET 200SP architecture; if using ET 200M, ET 200S, or other ET 200 families, different interface modules apply
  3. Check that your power supply can deliver 24 V DC at 550 mA maximum (or 450 mA typical), plus startup inrush of 3.7 A
  4. Confirm the number of I/O modules needed does not exceed 32 standard modules + 16 ET 200AL modules
  5. Verify STEP 7 software version (TIA Portal V14+ or STEP 7 V5.5 SP4+) is available for your configuration toolchain
  6. Ensure your network topology and cabling support 2-port RJ45 Ethernet switch configuration with autonegotiation
  7. Check installation orientation—vertical installations have lower max ambient temperature (50°C) vs. horizontal (60°C)

If any item on this checklist raises a question, contact the LeadTime.ca team before ordering — our technical team can verify compatibility against your system requirements before you commit to a purchase.

Frequently Asked Questions

Does the 6ES7155-6AU01-0BN0 support isochronous mode for motion control applications?

No. The IM 155-6PN Standard does not support isochronous mode. IRT frame times of 250 µs to 4 ms in 125 µs increments are supported for real-time I/O exchange, but applications requiring deterministic isochronous real-time synchronization for servo drives or synchronized motion axes should specify the 6ES7155-6HB02-0AB0 (IM 155-6PN HF) instead, which carries a 30–50% price premium over this module.

How many I/O modules can one 6ES7155-6AU01-0BN0 station support?

A single station supports up to 32 standard I/O modules and up to 16 ET 200AL modules, with a maximum of 256 submodules per station. If your application requires more than 32 standard I/O modules at a single network node, you will need to split the application across two separate ET 200SP stations, each with its own interface module.

What STEP 7 software version is required to configure the 6ES7155-6AU01-0BN0?

STEP 7 TIA Portal V14 or later is the recommended configuration environment. Legacy support is available for STEP 7 V5.5 SP4 or later. The module uses GSDML V2.35 for PROFINET device integration. If your toolchain runs an earlier version of STEP 7, a software upgrade will be required before commissioning.

Can I replace an I/O module in an ET 200SP station while the system is running?

Yes. The 6ES7155-6AU01-0BN0 supports single hot swapping of I/O modules during operation. This means a single module can be removed and a replacement inserted while the interface module remains powered and the PROFINET controller continues running. Note that hot swapping applies to one module at a time; simultaneous removal of multiple modules is not supported under this configuration.

What is the inrush current at startup and why does it matter for my panel design?

The maximum inrush current at startup is 3.7 A. If multiple ET 200SP stations are powered from the same 24 V DC bus simultaneously — for example, after a power restoration event — the combined inrush across multiple interface modules can trip upstream fuses or circuit breakers that are correctly sized for steady-state current only. Panel designers should verify that upstream protection devices are rated for the total inrush scenario, or stagger power-up sequences where necessary.

Is remanufactured stock a viable option for the 6ES7155-6AU01-0BN0?

Remanufactured units are available at 40–75% of new list price from reputable industrial parts suppliers. For MRO spares or cost-sensitive OEM builds, this is a practical sourcing option — provided the supplier offers a minimum 2-year warranty and can confirm the firmware version is V4.2 or later to match current STEP 7 TIA Portal requirements. For applications requiring a current hardware functional status (from FS03 onward), verify the hardware revision before accepting delivery.

Why Engineers Order This Part Through LeadTime.ca

  • Global shipping — LeadTime.ca sources and ships the Siemens 6ES7155-6AU01-0BN0 to customers worldwide, not limited to any single country or region
  • Hard-to-find and short lead time stock — LeadTime.ca specializes in locating industrial automation parts with compressed lead times, including modules with 4–8 week standard availability windows
  • Volume pricing — Orders of 5 or more units are eligible for quantity-based pricing discussion; contact the team with your build quantity before submitting an RFQ
  • Remanufactured and new options — Both new and verified remanufactured stock options are available to match your budget and warranty requirements
  • Technical pre-sales support — The LeadTime.ca team can verify part compatibility against your specific system architecture before you commit to an order

At-a-Glance Summary

  • Official product name: SIMATIC ET 200SP, PROFINET Interface Module IM 155-6PN Standard
  • Catalog number: 6ES7155-6AU01-0BN0
  • Maximum I/O capacity: 32 standard I/O modules + 16 ET 200AL modules = 256 submodules per station
  • Communication: PROFINET 100 Mbps full-duplex (100BASE-TX) via 2-port RJ45 switch with autonegotiation and autocrossing
  • Power supply: 24 V DC, 19.2 V to 28.8 V range; 450 mA rated, 550 mA maximum, 3.7 A inrush; reverse polarity and short-circuit protection built-in
  • Protocol support: PROFINET IO, PROFIsafe, PROFIenergy, PROFIBUS
  • IRT real-time frame times: 250 µs to 4 ms in 125 µs increments (isochronous mode not supported)
  • Operating temperature: 0°C to 60°C horizontal; 0°C to 50°C vertical; maximum altitude 5,000 m
  • Dimensions: 50 mm × 117 mm × 74 mm; weight 147 g without BusAdapter
  • Configuration software: STEP 7 TIA Portal V14+; legacy STEP 7 V5.5 SP4+; GSDML V2.35; firmware V4.2
  • Hot swap: Single I/O module hot swapping supported during operation
  • Includes server module: 6ES7193-6PA00-0AA0
  • Variant alternatives: 6ES7155-4BA02-0AB0 (half density, 20–30% lower cost) and 6ES7155-6HB02-0AB0 (IRT optimized, 30–50% higher cost)