In Focus
April 2, 1958 – Siemens registers SIMATIC trademark at German Patent Office / Launch of one of the world’s most successful automation systems
SIMATIC component, 1959
Erlangen, 1956. A small team of experts is gathered at the Siemens-Schuckert plant. Their job is to find out what the recently invented transistor can do for the electric power industry. The team is given free rein and develops something entirely new. At the Paris machine tool fair in 1959, Siemens proudly presents the first generation of its Building-Block System for Solid-State Controls: the SIMATIC G. These controls performed many functions, from summoning elevators when the "up" and "down" buttons were pushed, to directing machine tools to perform work according to a programmed sequence. Switching elements in that era’s conventional electromechanical systems were relays and contactors. But in the SIMATIC G, transistors performed these functions. Their advantage was that they were smaller and not subject to wear and tear. That’s why SIMATIC G was at first mainly used where highly reliable control elements were needed: in transformer substations and power plants.
A factor that helped SIMATIC gain ground was the very positive response to the arc control system developed in the early 1960s. Siemens equipped many transformer substations with this system, because these facilities often suffered short circuits caused by arcs resulting from operator errors in using the switchgear or from voltage surges due to lightning. The resulting damage was enormous and caused prolonged power blackouts. Arc extinction systems had to convert an arc into a harmless short circuit in a matter of milliseconds, which SIMATIC G could do thanks to its fast switching times.
The era of programmable logic controls (PLCs) began in the early 1970s. Their functions were not determined by hardware connections but by software, which made programming a lot easier. At the same time, computing power increased sharply. In 1965, a SIMATIC N module could perform 20 transistor functions and consequently 15 instructions per second. In the S5 module of 1988, the numbers had soared to about four million transistor functions and 32,000 instructions per second. As a result, SIMATIC could now perform higher-level tasks as well as control functions.
Sales quintupled in the two years following the market launch of the S5 systems in 1979. The S5 could manage automation, programming and documentation functions. The first so-called bus systems – which are indispensable for exchanging data and commands – were introduced shortly thereafter. These systems combined a large number of separate controls to form a single high-performance data network. In the 1990s, SIMATIC went on to become the core of a process control and management system that covered all automation tasks from the signal level to the control room terminal.
Since the launch of the first SIMATIC G, there have been a total of five generations of SIMATIC controls, each boasting an expanded range of functions. While the first generation was designed solely for programmed control functions, today’s SIMATIC-S7 system, as the core of Totally Integrated Automation (TIA), performs virtually every conceivable industrial automation task, from managing electric power generation to waste treatment, and from controlling transportation systems to manufacturing plants. Introduced in 2009, the TIA portal provides users with uniform access to all automation tasks.
Abridged version of an article by Luitgard Marschall; in: Pictures of the Future, Spring 2005
Further reading
Heinz Eisenbeiss, 50 Jahre Simatic – eine kleine Geschichte der Zeit; in: IT&Produktion, Zeitschrift für industrielle Informationstechnologie, Ausgabe HMI-Special 2008, pages 53–57
(in German only)
Rolf Hahn, Simatic Erfolg mit System. Vom Transistor zur Totally Integrated Automation, Munich 2001 (in German only)
Arnold Zankl, Meilensteine der Automatisierung. Vom Transistor zur Digitalen Fabrik. Erlangen 2006 (in German only)