Frank Suxdorf

Performance Aspects of PROFINET IO

Recently, the complex PROFINET CBA (component based automation) has been supplemented by the simplified PROFINET IO standard. PROFINET CBA defines a vendor-independent engineering model covering plant-wide automation and uses a component/container approach. Contrary to this, PROFINET IO aims at decentral periphery scenarios. Analogous to PROFIBUS DP it is based on a modular device model. Functionally, PROFINET IO can be considered as an Ethernet-based fieldbus. It is expected that PROFINET IO will play a major role on the PLC market since it is a possible replacement for PROFIBUS DP. The paper introduces the PROFINET technology and discusses performance aspects. Measurement results are presented.

Measurement of real-time aspects of Simatic/spl reg/ PLC operation in the context of physics experiments

Today, most slow control systems for physics experiments at Forschungszentrum Ju/spl uml/lich are implemented with Programmable Logic Controller (PLC) technology and fieldbus systems. In many cases, even deterministic response is required from the PLCs. This raises the question about the real-time performance that can be expected from a PLC. Response-time measurements of Simatic/spl reg/ PLCs-manufactured by the world market leader Siemens-are presented. Influence of program structure and hardware configuration on performance and deterministic behavior of a PLC is discussed.

The high-intensity reflectometer of the Jülich Centre for Neutron Science: MARIA

MARIA is a world class vertical sample reflectometer dedicated to the investigation of thin films in the fields of magnetism, soft matter and biology. With the elliptical vertically focusing guide and a wavelength resolution of Δλ/λ = 10%, the non-polarized flux at the sample position amounts to 1.2 × 108 n (s cm2)−1. Besides the polarized and non-polarized reflectivity mode for specular and off-specular reflectivity measurements, MARIA can also be used to carry out grazing-incidence small-angle neutron scattering investigations.

MWPC-readout with the N110 TDC under Linux using a flexible, low-cost FPGA solution

For X-ray spectroscopy at the plasma physics tokamak TEXTOR in Forschungszentrum Julich three N110 TDC modules (developed by Christian Herve, ESRF, Grenoble) are used for the readout of multi-wire proportional counters (MWPC). An optimized low-cost FPGA-based CompactPCI board was developed, that interfaces the N110 and the TEXTOR timing system. The implemented software consists of a Linux device driver and a measurement application program. The Linux device driver is responsible for the transfer of list-mode detector and timing data via DMA into the main memory of a PC. After each TEXTOR shot the application program transfers the data from RAM to disk and adds administrative shot information automatically. Three boards can be read out by one PC simultaneously at the maximum speed of the N110

MWPC readout with the GPX ASIC

For X-ray spectroscopy at the plasma physics tokamak TEXTOR in Forschungszentrum Julich a TDC module has been developed for the readout of multi-wire proportional counters (MWPC). The new board comes in CompactPCI form factor and is based on the GPX TDC ASIC from acam messelectronic GmbH. In the selected mode I-mode the GPX has 8 input channels with a typical resolution of 81 ps. The implemented software consists of a Linux device driver and a measurement application program. The Linux device driver is responsible for the transfer of list-mode data via DMA into the main memory of a PC. After each TEXTOR shot the application program transfers the data from RAM to disk and automatically adds administrative shot information.

Towards wide-angle neutron polarization analysis with a 3He spin filter for TOPAS and NEAT: Testing magic PASTIS on V20 at HZB

An XYZ polarization analysis solution has been developed for the new thermal time-of-flight spectrometer TOPAS [1], to be operated in the coming east neutron guide hall at the MLZ. This prototype is currently being prepared to use on NEAT at HZB [2]. Polarization Analysis Studies on a Thermal Inelastic Spectrometer, commonly called PASTIS [3], is based on polarized 3He neutron spin filters and an XYZ field configuration for the sample environment and a polarization-preserving neutron guide field. The complete system was designed to provide adiabatic transport of the neutron polarization to the sample position on TOPAS while maintaining the homogeneity of the XYZ field. This complete system has now been tested on the polarized time-of-flight ESS test beam line V20 at HZB [4]. We present results of this test and the next steps forward.

Neutron Detector Data Acquisition for a Spin Echo Instrument at a Spallation Source

For a spin echo instrument installed at the SNS (Oak Ridge, TN) a position sensitive detector based on the MWPC principle is being used. The data acquisition electronics is based on a development for X-ray spectroscopy, using delay lines and N110 TDCs (ESRF, Grenoble, France). Some modifications were necessary to adapt to the timing requirements at the pulsed neutron source. The design of the data acquisition system and the interface to the SNS timing system is described.