Researchers at Uppsala University are developing a flywheel energy storage device intended to be used in electrical vehicles. Kinetic energy storage technology has potential to make purely electric powertrain both more effective and efficient. While deployment of the third prototype is approaching there has been a request for a more precise and noise-immune circuitry to power active magnetic bearings that hold and stabilise the rotor. A similar circuit designed for powering electromagnets was recently developed at the Uppsala University’s Electricity department and is used as a template in development of the new active magnetic bearing driver circuit. Current measurement integration technique is tested and implemented as a way to increase circuit’s control feedback loop performance. To further boost precision and noise-immunity 0-20 mA current loop signals are adapted as the standard for output signals. Results of this project include a thorough analysis of the electromagnet driver circuit development, implementation of a new current sensing technique including an experimental self-inductance measurement, printed circuit board layout design and a full list of components necessary to power and control two sets of active magnetic bearings consisting of 8 individual electromagnets.

The subject of master´s thesis the problematics of current loop. Within the thesis, the basic components of current loop and the possibilities of its usage are described. There has also been an analysis made of the crucial functions of analyzer which is currently being in the process of development. A focus is put on mode of source and measure. The related functions are crucial in terms of testing and simulation of current loop. Furthermore, the SPI is described and it is used to establish access to the analyzer’s display. The usage of FMEA method has been chosen for the purpose of circuit’s reliability assessment. Practical part describes development of the analyzer and its parts. FMEA method application for selected fault states is presented in final part.

This diploma thesis describes design and development of creating field instrument demonstration kit. Kit is capable of measuring multiple sensors such as thermocouples, RTDs, or pressure sensors, analogue sensor simulation is also provided. Sensor’s side is isolated from output, which is composed of 4 - 20 mA current loop and HART interface. Current loop also provides power supply and kit can communicate via HART also when alarm current (3,2 mA) is set. Basic safety features like open wire detection, over and undervoltage protection are also implemented.

This work is aimed on design of a device for testing of fire detectors and various components of fire detection system, communicating with the fire panel over a fire bus or a loop. The device generates voltages, supplying the detectors, as well as communicating over the bus generating communication waveforms and performing detection of responses measuring voltage and current on the connection. The loop signal is processed by the developed unit and data or result sent to a PC utilizing USB or RS232 connection. All the parts of the equipment are galvanically isolated to the loop circuit.

The dissertation deals with a design of an intelligent transmitter of a standard current signal with an Ethernet output port, an implementation of a web interface and Modbus TCP protocol for providing data protection. The introductory part describes standardized analogue technical signals with their possibilities, and characteristics of industrial Ethernet. The subsequent part provides an overview of alternatives to connect analogue signals to Ethernet while using various modules. The thesis continues with a suggestion of an analogue input side of the transmitter in connection with a digital module of Ethernet based on the Rabbit processor in connection with the RCM3200 module. The key part of the dissertation puts forward a proposal of the firmware transmitter and control web interface, shows ways of providing figures measured by the current loop via Ethernet interface for further processing. The final part is devoted to a description of current transmitter ultimate measurement.

Målsättningen med rapporten är att bestämma på vilket sätt det går att hantera problem med gamla komponenter som går sönder på produktionslinjen som behöver ersättas med modernare utrustning. Att analysera valet till metod och val av passande ersättande komponenter, då valet kan vara kritisk för anläggningens funktion. Att jämföra de kommunikationsgränssnitt som används i arbetet i from av överföringshastigheter, distanser och funktion. Arbetet går igenom kommunikationsgränssnitt som PROFINET, RS-232, HART, Siemens protokollet RK 512 och proceduren 3964R. Hur signalöverföring med Current Loop fungerar. Arbetet visar hur det är möjligt att återfinna gamla data från produkter som installerats decennier tidigare genom litteraturstudie och mångsidig testning. Beroende på vilken situationen är i industrin och planer för framtida maskinuppgraderingar kan lösningsmetoden variera för att framtidssäkra produktionen med ny teknik eller med nya komponenter.  Resultatet av arbetet gav åter igen en fungerande produktionslinje. Kommunikationsgränssnitt som PROFINET är superiör med snabb överföringshastighet, långt kabelavstånd och skydd mot EMC. Vilket gör den till ett framtidssäkert gränssnitt. Till skillnad från äldre gränsnitt som den väletablerade RS232 som har långsam dataöverföring, korta kabelavstånd och är känslig för EMC. HART är ett flexibelt kommunikationsgränssnitt som använder Current Loop för signalöverföring. Eftersom gränssnittet använder ström möjliggör det mycket långa kabelavstånd och skydd mot EMC, men långsam datahastighet. / The aim of the report is to determine how to deal with problems with old components that break on the production line that need to be replaced with modern equipment. To analyse the choice of method and choice of suitable replacement components, as the choice can be critical for the plant's function. To compare the communication interfaces used in the work in the form of transmission speeds, distances, and function. The work goes through communication interface such as PROFINET, RS-232, HART, the Siemens protocol RK 512 and the procedure 3964R. How signal transmission with Current Loop works. The work shows how it is possible to find old data from products that were installed decades earlier through literature study and versatile testing. Depending on the situation in the industry and plans for future machine upgrades, the solution method can vary, as you want to secure the future of production with new technology or with new components. The result of the work once again gave a functioning production line. Communication interfaces such as PROFINET are superior with fast transmission speeds, long cable distances and protection against EMC. Which makes it a future-proof interface. Unlike older interfaces such as the well-established RS232 which has slow data transfer, short cable distances and is sensitive to EMC. HART is a flexible communication interface that uses the Current Loop for signal transmission. Because the interface uses current, it provides very long cable distances and protection against EMC, but slow data speeds.

International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Although PCM/TDM framed data is one of the most prevalent formats handled by flight test ranges, it is often required to acquire and process other types. Examples of such non-standard data types are radar position information and meteorological data from both ground based and radiosonde systems. To facilitate the process and management of such non-standard data types, a micro-processor based system was developed to acquire and transform them into a standard PCM/TDM data frame. This obviated the expense of developing additional special software and hardware to handle such non-standard data types.

This thesis describes the possibilities of local and remote sensors configuration. Summary overview of the most common Fieldbus and protocols for remote configuration is performed. The focus is mainly dedicated to the HART protocol that is analyzed from the physical layer to the application layer. Circuit diagram and printed circuit board (PCB) of smart sensor with thermistor probe Pt1000 was designed. The HART protocol allows the smart sensor parameters setting as well. The functionality of remote configuration was tested in HARTWinConf program. The control elements for local sensor configuration, such as buttons, matrix keyboards and touchscreens, are described in the following chapter. Representation of the measurement values on display module is introduced too. The most important parameters and aspect of character LCD, graphics LCD and OLED displays are described in greater details. The DD12864YO-3A OLED display was selected to use with designed temperature smart sensor module. The display shows the loop current, the percentage of current range and the primary value - temperature. As the last step the EMI and EMS tests for all modules were performed.

This thesis is concerned with the measurement of physical quantities. Thesis describes sensors in general terms and requirements, which delivers latest trends in the field of automation. The main theme of this thesis is sensors for meassuring pressure, and their connection to the automation chain. In the next part thesis describes the design of the converter for connecting SMART sensors for pressure measuring, that use HART communication protocol, to the automation systems managed by a communication protocol IO-link. First will be described in detail various communication standards by their ISO OSI model, and on this theoretical basis will be based design of converter between communication protocol HART and communication protocol IO-Link. The last part will be Designed software for this converter.

In control technique there is evident highly expressive trend of shifting from efficient central managing systems towards smaller systems which are distributed on technology and which are connected by communication bus. There is no need to link all signals to central management system, operation is then distributed and realized directly in individual parts of technology. That’s why these systems are called distributive managing systems. Distributive managing systems are widely used not only in industrial applications but also in buildings, cars, etc..