Migration of legacy systems and 3rd party


Control system migration: From old to new - with strategy, experience and understanding!

Control systems only have a finite service life and must be replaced at some point. Most plant operators fear this unavoidable step. The good news: Intelligent control system migrations often save a complete replacement at once. For a transition to a new system that is as economical and risk-free as possible, the renewal, maintenance and adaptation of existing hardware and software can be put into an optimal relationship through experience and planning. Siemens therefore offers comprehensive migration strategies - not only for its own legacy systems, but also for systems from other manufacturers. 

Benefit from further technological developments:

Migration - our experience for your success

With the large number of process control systems in use since the 1980s and 1990s, medium- and long-term migration planning in view of declining support and dwindling know-how becomes a decisive prerequisite for not simply keeping plants running. Rather, it is a matter of modern adaptation of technology to increased requirements with regard to flexibility, product quality, resource savings and documentation. A modern process control system such as SIMATIC PCS 7 offers immense advantages over legacy systems that need to be utilized. We know: Each plant is unique and therefore each migration project has its own specific challenges and constraints. Our experienced migration engineers will work with you to find the right approach to modernizing your legacy systems: in one go, in large or small steps.

Migrations are modernizations that not only aim to secure the availability of the control system for the future, but also to initiate a generational change in the truest sense of the word and thus to profit from the various characteristics and possibilities that a modern system offers today.

Based on a comprehensive analysis of the existing installation(s), we develop and recommend a migration strategy that exactly meets your conditions and goals. It answers some basic questions:

  • Which systems should be migrated primarily to SIMATIC PCS 7, for which there is more time available?
  • Which migration paths (complete exchange or step-by-step migration) are suitable under the given conditions?
  • Which advantages can be generated from a tool-based implementation of the existing engineering?
  • What new possibilities for controlling and optimizing your production processes and the required resources will result from the introduction of a modern control system?
  • What return on investment can you expect from the potentials of SIMATIC PCS 7?

With Siemens as your partner, you can not only master a single migration project, but also work out a comprehensive migration strategy for years and many of your sites that will take you a decisive step further towards the goal of modernizing and standardizing your control system landscape.

Many of the process control systems installed worldwide are approaching the end of their life cycle. These include systems such as TELEPERM M, APACS+/QUADLOG, TI505, Bailey INFI 90, PMC/OpenPMC, SIMATIC S5 and other systems from other manufacturers. Since individual components have become obsolete or can no longer be repaired, it is urgently necessary to modernize these systems. Because hardware, application software and the know-how of the operating and maintenance personnel represent an enormous value, we offer you individual migration solutions. However, a step-by-step migration is often preferred over a complete replacement of the system (Rip-out and Replace).


The following basic migration scenarios can be differentiated:

  • The ideal solution for modernizing the operating level of all systems that provide an OPC server: In such cases (this includes third-party process control systems as well as control systems), the existing operating system can be conveniently replaced by PCS 7/OpenOS - whether in the course of a modernization or to integrate existing controllers into an automation solution with SIMATIC PCS 7.
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  • Replacing older controllers with modern PCS 7 controllers: This gives you a clear improvement in performance and functionality. An examination of whether the use of our powerful implementation tools for controller engineering can save a considerable amount of time and money is essential for this step. Our experts implement your engineering, optimized over many years, on SIMATIC PCS 7 in such a way that it does not differ from a new engineering: Not building block by building block, but on the level of technological functionality. Thus you preserve the valuable know-how from the old system, and nevertheless all functions of the new control system are available to you without restriction.
  • Replacing I/O modules and the associated wiring with thousands of process signals is extremely time consuming and costly. Discover our I/O modules that can be easily and flexibly integrated into existing systems. 
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TELEPERM M is a process control system that set standards until the mid-90s. Despite various modernization measures, many system components are already outdated and no longer meet today's requirements. In order to be able to produce at a high quality level in the long term, it will sooner or later be necessary to switch to a new system generation. The successor system SIMATIC PCS 7 is established in all industries and is reliably able to replace TELEPERM M without interruption.

Since 1999, a comprehensive range of migration services has facilitated the step-by-step transition to the new SIMATIC PCS 7 system platform. The complete replacement of the installed base by SIMATIC PCS 7 system components with new software has been largely completed. Selected components from this product range as well as technical support are, however, still available under a service agreement. With this offer, the operation of an existing plant up to a planned modernization is ensured and thus a contribution to investment protection is available.


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The OpenPMC Operator System has been on the market for several years and, taking into account its product life cycle, we are paving the way for you today to our future-proof and proven SIMATIC PCS 7 control system. With this innovative and powerful process control system, you are on the safe side in regards today's and tomorrow's requirements. It goes without saying that we support you during the migration with our experience.


For further information please contact the regional contact person. 

The migration of a process control system based on APACS+/QUADLOG controllers with the innovative SIMATIC PCS 7 OS operating and monitoring systems from Siemens offers the opportunity to preserve proven features and at the same time significantly increase functionality and performance through specific modernization. Existing operator and engineering systems can be modernized with SIMATIC PCS 7 while retaining the APACS+/QUADLOG controllers and the underlying I/O level. This enables customers to migrate their existing system efficiently and economically without having to replace controllers, I/O devices or their wiring and abandon the associated investment in system configuration.
With the SIMATIC PCS 7 automation systems AS 410, you also have excellent alternatives on the controller level, especially for plant expansions. These are supported by controller-controller communication via Industrial Ethernet Modules (IEM) and by SIMATIC PCS 7/APACS+ operator systems, which can communicate via DualChannel with APACS+/QUADLOG controllers as well as with AS 410 systems.

The migration strategy developed by Siemens on the basis of the innovative SIMATIC PCS 7 process control system supports a variety of scenarios that enable you to minimize the investment requirements for your individual automation project. By modernizing process control with SIMATIC PCS 7, the functionality and performance of existing Bailey INFI 90/NET 90 systems can be significantly increased without replacing the controllers and the underlying I/O level. Plant extensions also offer you the option of using SIMATIC PCS 7 AS 41x automation systems and SIMATIC process peripherals.

The extensive controller portfolio of SIMATIC S5 was the first choice for the most diverse control tasks in the process industry and in production automation for two decades. As the S5 product line ages, maintenance of these control systems becomes more difficult and costly. At the same time, accelerated technical change and more stringent market requirements place high demands on today's automation systems. A migration from SIMATIC S5 controllers to SIMATIC PCS 7 and the current controller generation is a sensible step.

For further information please contact the regional contact person.

SIMATIC PCS 7 in the Metals Industry – More than Doubling the Capacity without Stopping Production

SIMATIC PCS 7 and Finze & Wagner – Optimum Cooperation for Process Automation at Nestlé

Migration of the process control system to SIMATIC PCS 7 at Janssen Pharmaceutica

Many installed process control systems worldwide are approaching the end of their life cycle. For long-term economic plant operation, they must be partially or completely modernized. Siemens is not only your competent partner for the modernization of our own systems. Here is a selection of successfully migrated systems to SIMATIC PCS 7:

ABB Contronic P, Symphony, System6 and Sattline, Emerson RS/3 and Provox, Honeywell TDC 2000 and 3000 - these are just some of the process control systems from other manufacturers for which we offer effective migration solutions. PLC/SCADA systems such as AEG Modicon, or controllers from Rockwell and other suppliers can also be migrated to SIMATIC PCS 7.

Depending on the system and conditions of your plant, different migration approaches are possible, e.g.

  • Modernization of the HMI level,
  • Controller migration with or without integration of existing I/Os,
  • Cable solutions to maintain existing field wiring,
  • tool-supported migration of engineering data,
  • or a total replacement of the existing system.

For further information please contact the regional contact person.



Learn more…

Learn more about the extensive possibilities for the individual modernization of your control systems. The documents in the download area deepen certain aspects and inform you about special functions.

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