Find Siemens S7-400 Parts — Obsolete, Discontinued & Hard-to-Find

Looking for a Siemens S7-400 CPU, I/O module, power supply, communication processor, rack or other component that is no longer readily available?

S7Automation supplies new, surplus and professionally refurbished Siemens S7-400 parts for industrial maintenance, emergency replacement and long-term spare-parts requirements.

We help companies keep existing S7-400 automation systems running without immediately replacing an entire PLC installation.

Can’t find your part?

Send us the complete Siemens part number, a photograph of the module or your equipment requirements.

Request a Quotation today

Siemens S7-400 Obsolete Parts

The Siemens SIMATIC S7-400 was designed for demanding industrial automation and process-control applications where high performance, large configurations and extensive communication capabilities were required.

Many S7-400 systems remain installed in factories, process plants, power facilities, infrastructure and other critical industrial applications.

As individual S7-400 components enter product phase-out or cancellation stages, sourcing replacement hardware through conventional distribution channels can become increasingly difficult.

S7 Automation specializes in sourcing obsolete, discontinued and hard-to-find Siemens automation components, including S7-400 products.

When a critical component fails, sourcing the original part can often be considerably faster and less disruptive than immediately migrating the entire control system.

Siemens S7-400 Parts We Supply

Our S7-400 inventory can include a wide range of original Siemens components, depending on current stock.

S7-400 CPUs

We can source Siemens S7-400 CPU modules including:

6ES7412-1XF02-0AB0 — CPU 412-1
6ES7413-1XG02-0AB0 — CPU 413-1
6ES7413-2XG02-0AB0 — CPU 413-2 DP
6ES7414-1XG02-0AB0 — CPU 414-1
6ES7414-2XG02-0AB0 — CPU 414-2 DP
6ES7414-2XJ01-0AB0 — CPU 414-2 DP
6ES7414-3XM07-0AB0 — CPU 414-3 DP
6ES7414-3EM07-0AB0 — CPU 414-3 PN/DP
6ES7416-1XJ02-0AB0 — CPU 416-1
6ES7416-2XK01-0AB0 — CPU 416-2 DP
6ES7416-2XL01-0AB0 — CPU 416-2 DP
6ES7416-2XP07-0AB0 — CPU 416-2 DP
6ES7416-3XL04-0AB0 — CPU 416-3
6ES7416-3XS07-0AB0 — CPU 416-3 DP
6ES7416-3ES06-0AB0 — CPU 416-3 PN/DP
6ES7416-3ES07-0AB0 — CPU 416-3 PN/DP
6ES7417-4XL00-0AB0 — CPU 417-4
6ES7417-4XL04-0AB0 — CPU 417-4
6ES7417-4XT07-0AB0 — CPU 417-4

Siemens documentation confirms these S7-400 CPU order numbers and their associated CPU variants.

Siemens S7-400 H-CPU & Redundant Systems

S7-400H systems are used in applications where high availability and redundancy are critical.

S7Automation can help source original and refurbished H-CPU components, including:

6ES7412-3HJ14-0AB0 — CPU 412-3H
6ES7414-4HJ00-0AB0 — CPU 414-4H
6ES7414-4HM14-0AB0 — CPU 414-4H
6ES7417-4HL00-0AB0 — CPU 417-4H
6ES7417-4HL01-0AB0 — CPU 417-4H
6ES7417-4HT14-0AB0 — CPU 417-4H

These CPUs are particularly important for process industries and other installations where PLC redundancy and availability are critical. Siemens documentation identifies these exact order numbers for S7-400H CPUs.

Siemens S7-400 Power Supply Modules

We can also help source obsolete and replacement S7-400 power supplies.

Common S7-400 power supply order numbers include:

6ES7405-0KA02-0AA0
6ES7405-0KR02-0AA0
6ES7405-0RA02-0AA0
6ES7407-0DA02-0AA0
6ES7407-0KA02-0AA0
6ES7407-0KR02-0AA0
6ES7407-0RA02-0AA0

These include PS 405 and PS 407 families used in S7-400 installations. Siemens’ S7-400 module documentation lists these exact order numbers.

Need a replacement power supply?

Send us your complete Siemens MLFB number.

We can check for:

Original part → New surplus → Refurbished original → Siemens successor

Siemens S7-400 Digital Input Modules

S7Automation can source S7-400 SM 421 digital input modules, including:

6ES7421-1BL00-0AA0 — SM 421, 32 DI, 24 VDC
6ES7421-1BL01-0AA0 — SM 421, 32 DI, 24 VDC
6ES7421-1EL00-0AA0 — SM 421, 32 DI, 120 V
6ES7421-1FH00-0AA0 — SM 421, 16 DI, 120/230 V
6ES7421-1FH20-0AA0 — SM 421, 16 DI, 120/230 V
6ES7421-7BH00-0AB0 — SM 421, 16 DI, 24 VDC
6ES7421-7BH01-0AB0 — SM 421, 16 DI, 24 VDC
6ES7421-7DH00-0AB0

Siemens documentation confirms these S7-400 digital-input MLFB numbers.

Siemens S7-400 Digital Output Modules

Available S7-400 SM 422 families can include:

6ES7422-1BH11-0AA0
6ES7422-1BL00-0AA0
6ES7422-1FH00-0AA0
6ES7422-1HH00-0AA0
6ES7422-7BL00-0AB0

These modules cover different S7-400 digital-output configurations and are documented in Siemens’ S7-400 module data.

Siemens S7-400 Analog Input Modules

S7-400 analog input modules include several SM 431 variants.

Examples include:

6ES7431-0HH00-0AB0
6ES7431-1KF00-0AB0
6ES7431-1KF10-0AB0
6ES7431-1KF20-0AB0
6ES7431-7KF00-0AB0
6ES7431-7KF10-0AB0
6ES7431-7QH00-0AB0

These modules cover different analog input configurations used throughout S7-400 systems.

Siemens S7-400 Analog Output Modules

S7-400 analog output modules include:

6ES7432-1HF00-0AB0

The 6ES7432-1HF00-0AB0 is an S7-400 analog output module and is included in Siemens’ official module documentation.

Siemens S7-400 Interface & Expansion Modules

S7-400 systems can use a range of interface and expansion modules.

Examples include:

6ES7460-0AA01-0AB0
6ES7460-1BA00-0AB0
6ES7460-1BA01-0AB0
6ES7460-3AA01-0AB0
6ES7461-0AA01-0AA0
6ES7461-1BA00-0AA0
6ES7461-1BA01-0AA0
6ES7461-3AA01-0AA0

These are listed in Siemens’ S7-400 module documentation.

Siemens S7-400 Communication & Networking

S7-400 installations may also contain communication processors and networking modules from the Siemens CP 443 and related families.

Typical search terms include:

Siemens CP 443-1
Siemens CP 443-1 IT
Siemens CP 443-2
Siemens CP 443-5
Siemens CP 443-5 Extended
Siemens IM 467
Siemens S7-400 PROFIBUS modules
Siemens S7-400 Industrial Ethernet modules
Siemens S7-400 PROFINET modules

For communication components, always provide the complete MLFB number, because multiple hardware revisions can exist within the same product family.

Siemens S7-400 Racks & Hardware

S7Automation can also help source S7-400 rack and system hardware.

Relevant S7-400 families include:

6ES7400
6ES7401
6ES7403
6ES7490
S7-400 UR racks
S7-400 CR racks
S7-400 ER racks
Central racks
Expansion racks
Rack accessories
Bus and connection components

Examples of documented S7-400 rack-related order numbers include:

6ES7400-1TA11-0AA0
6ES7400-2JA00-0AA0
6ES7400-2JA10-0AA0
6ES7401-1DA01-0AA0
6ES7401-2TA01-0AA0
6ES7403-1JA01-0AA0
6ES7403-1JA11-0AA0

Siemens’ official S7-400 module documentation lists these product numbers.

S7-400 Obsolete Part Number Search

If you are searching for a specific Siemens S7-400 component, use the complete MLFB / order number.

Examples:

6ES7414-3XM07-0AB0

6ES7416-2XP07-0AB0

6ES7417-4XT07-0AB0

6ES7407-0DA02-0AA0

6ES7421-1BL01-0AA0

6ES7422-1BL00-0AA0

6ES7431-1KF00-0AB0

6ES7432-1HF00-0AB0

The complete order number is important because different hardware revisions and versions can have different MLFB numbers.

S7-400 CPU Replacement Parts

A failed S7-400 CPU can result in significant production downtime.

Rather than immediately replacing an entire control system, the first step is to identify whether the exact CPU or an appropriate replacement is available.

S7Automation can help source original S7-400 CPUs in different conditions, including new surplus and professionally refurbished units.

Looking for a replacement?

Send us your complete Siemens MLFB.

We can investigate:

Exact original

The same Siemens order number, where available.

Newer Siemens replacement

A documented successor where one exists.

Refurbished original

A professionally tested original S7-400 CPU.

Alternative solution

Another technically suitable option where appropriate.

System migration

For installations reaching the end of their useful life, we can help you investigate modernization options.

[ FIND MY S7-400 REPLACEMENT ]

New, Surplus or Refurbished S7-400 Parts

Depending on the product and current inventory, S7Automation may offer several purchasing options.

New

Original Siemens components in new condition where available.

New Surplus

Genuine Siemens equipment sourced from surplus industrial inventory.

Professionally Refurbished

Previously used components that have been inspected and tested before shipment.

24-Month Warranty

Eligible S7Automation products are supplied with a 24-month warranty.

Why Buy S7-400 Parts from S7Automation?

Obsolete Siemens Expertise

We specialize in sourcing Siemens automation components that are difficult to obtain through conventional channels.

Large Inventory

Our inventory includes a wide range of Siemens PLC, HMI, drive and industrial automation components.

24-Month Warranty

Eligible parts are supplied with a two-year warranty.

Technical Support

Our team can help identify the correct Siemens part number and investigate replacement options.

European Stock Network

S7Automation works with a network of European partner warehouses.

Worldwide Supply

We supply industrial customers internationally.

S7-400 Parts for Industrial Maintenance

S7-400 systems remain installed across many industries where reliability and continuity of production are critical.

Our customers use S7-400 replacement components in:

Oil & Gas
Refineries
Petrochemical plants
Chemical processing
Power generation
Water treatment
Manufacturing
Automotive
Marine
Food & Beverage
Pharmaceutical production
Mining
Infrastructure
Process automation

Don’t Replace the Entire S7-400 System Yet

A failed module doesn’t necessarily mean that the entire automation system needs to be upgraded.

A complete PLC migration can involve:

New hardware
Engineering
PLC programming
HMI modifications
Panel modifications
Communication changes
Factory acceptance testing
Site commissioning
Production downtime
Operator training

For an urgent failure, finding the original S7-400 component may be the fastest way to restore production.

You can then plan a modernization project on your own schedule, rather than being forced into an emergency migration.

S7-400 Obsolete Part Identification Service

Don’t know the exact part number?

We can help.

Send us:

Siemens Part Number

For example:

6ES7414-3XM07-0AB0

Photograph

Send a clear photograph of the Siemens label.

Quantity

Tell us how many units you require.

Application

Tell us what the component does if the part number isn’t available.

Urgency

Let us know if the machine or production line is currently stopped.

[ SEND YOUR S7-400 PART NUMBER ]

Frequently Asked Questions

Is the Siemens S7-400 obsolete?

The S7-400 platform is a mature automation platform, and individual products have different lifecycle statuses. Some components have been discontinued or phased out while others have defined successor products.

Always check the lifecycle status of the exact MLFB number, rather than assuming that every S7-400 product has the same status.

Can I still buy Siemens S7-400 CPUs?

Yes. Availability depends on the exact MLFB and current market inventory. S7Automation supplies selected S7-400 CPUs as new, surplus or refurbished products.

Do you sell refurbished S7-400 parts?

Yes. Selected S7-400 components can be supplied professionally refurbished and tested, subject to availability.

Do refurbished S7-400 parts have a warranty?

Eligible S7Automation products are supplied with a 24-month warranty.

Can you find discontinued S7-400 parts?

Yes. Send us the complete Siemens part number and we can check available inventory and sourcing options.

Can you identify an S7-400 module from a photograph?

In many cases, yes. Send a clear photograph showing the Siemens label and order number.

Can you find a replacement for my discontinued S7-400 CPU?

Yes. We can investigate the original part, Siemens successor, refurbished replacement and other available options.

Do you supply S7-400 parts internationally?

Yes. S7Automation supplies Siemens automation components to customers internationally through its European stock and partner warehouse network.

Should I replace my S7-400 with an S7-1500?

Not automatically. If a critical component has failed, replacing the individual component may be the fastest and least disruptive solution. A migration can be evaluated separately based on the age and requirements of the installation.