DISCOVER May 1/2005 CPUs in teaching and research A CPU for all Occasions In France and Germany, CPUs from the Simatic S7-300 product range are also gaining in popularity in the world of higher education. Given their versatile capabilities, this comes as no surprise. The safety professional: CPU 315F-2 DP At the new European Competence Center for Safety Technology at ENSAM University in Metz, France, Simatic S7-300F has already become a fixed variable. At level 3 of the "Safety Integrated" security concept, alongside S7-400F, this CPU is realized as a standard control with integrated safety function. If an error occurs, safe Simatic controls are used to ensure the Young engineers using Siemens systems for safety engineering training at the European Competence Center application is flexibly transferred into or kept in a safe mode. For this purpose, the fail-safe CPU 315F-2 DP features comprehensive autonomous testing and self-diagnosis functions. It also offers functions such as the processing of standard and fault-tolerant programs on one CPU, fail-safe slave-to-slave communication between intelligent DP slaves, as well as the usual diagnosis and alarm functions of the standard Simatic S7-CPU. All programming is performed using step 7 in the standard languages LAD and FBD. The software package "S7 Distributed Safety" supports the failsafe I/Os for parameterization and supports programming with readymade certified modules. Fit for PROFINET: CPU 315-2 PN/DP A CPU 315-2 PN/DP is currently being used in the University of Duisburg-Essen (Germany). Profi- net is one of the technologies being studied as part of an experiment on "networked" systems for control and error diagnosis. The study is using Profinet communication between an ET 200 and S7-315 PN. The CPU enables the connection of I/O and field devices via Profinet, such as the distributed I/O Simatic ET 200S with Profinet interface connection. The additional integrated Profibus interface can also be used to connect field devices as before – and the Profinet interface is then used for communication at cell level. The Profinet CPU can be programmed using a central programming device or PC via Industrial Ethernet with Step 7. The necessary driver is included in Step 7. The devices of the underlying Profibus can also be accessed from here without the need to reconnect the programming device. The highlights of the CPU include integrated interfaces, which prevent the need for additional modules. The CPU also features continuous communication from control level to field level, an application option as a gateway from Profinet/Ethernet to Profibus, and flexible maintenance using the innovative Micro Memory Card. Scalable for Motion Control: CPU 315T At the University of Wuppertal (Germany), the automation of a guideway grinding machine using a CPU 317T is currently the subject of a dissertation in the faculty of Electronics, Information and Media Technology. The CPU 315T combines the Simatic standard CPU and the high-performance PLCopen- certified Motion Control functions: Fast, deterministic controller cycles enable the high performance control of up to eight axes – in isochronous mode. Like the CPU 317T, the CPU 315T also possesses a fast local digital I/O device and two Profibus interfaces. The underlying technology structure of the control includes 32 technology objects. These are composed of a maximum of eight axes, 16 cams, 16 output cams, and eight measuring probes and external sensors. A range of features make the CPU interesting for education: simplified and fast engineering through the integration of technology and motion control in Step 7, easy-to-understand motion functions based on the international standard PLCopen, the initial operation tool "axis control panel" for moving the axes without the S7 program, the trace tool for continual recording or real-time monitoring of target and actual values, as well as the fast Fourier transformation for analysis of the frequency spectrum.