Z. Watral

Practical validation of a flow meter design environment

There are many methods used for flow measurement. Among them, the electromagnetic method is unique because it is able to conduct measurements in open channels that carry polluted liquids with variable and axially asymmetric velocity profiles. This type of channel is encountered in sewage treatment plants and irrigation systems. The electromagnetic method of flow measurement is also used when the relationship between flow and liquid level is unknown. This paper concentrates on some aspects of designing an electromagnetic flow meter for an artificial channel with a rectangular cross-section a situation often encountered in wastewater treatment plants or irrigation systems.

Selected problems of power sources for wireless sensors networks [instrumentation notes]

The issue of using renewable energy sources to generate electrical power for wireless sensor networks has been the subject of extensive research for at least a decade. The main reason for the dynamic development of this research was the need to supply operating power for wireless sensor networks deployed in areas without access to the electrical grid. Power required to supply each node of the network varies from tens of milliWatts to tens of Watts. This allows you to search for customized solutions in a wide range of phenomena.

Universal Magnetic Circuit for Resolvers with Different Speed Ratios [Instrumentation Notes]

This paper proposes a universal magnetic circuit for resolvers with different speed ratios. A resolver is an electromechanical transducer that converts the angular position of a rotor into an electric signal. The analysis and test results led to the conclusion that by using an appropriate magnetic material and assuring high-precision manufacturing it is possible to obtain high-precision resolvers with electrical error well below 1 minute of arc. Also it was proved that by using a single type of magnetic circuit it is possible to create multipole, two-speed resolvers. This system is used to improve both accuracy and resolution of angle measurement.

The problems of pulse excitation in electromagnetic flowmeters [Instrumentationnotes]

The advent of low cost microcontrollers and the development of DSP technology, intelligent data collection and processing, wireless communication, sharing of system resources, and self-identification has made distributed measurement systems extremely efficient, adaptive, and user friendly. These technologies and systems, however, require energy when operating in off-the-grid conditions, especially in environment monitoring. In such cases, a measurement subsystem of low energy consumption and a hybrid power station equipped with sources of renewable energy is the only reasonable solution.

Development of the substitutive circuit for the electromagnetic flowmeter

The paper presents the results of measurements of the electrical properties of the sensor in the electromagnetic flowmeter. The RC network and its parameters were identified for it. The influence of them on the LS flow velocity estimation in the pulse mode was also examined by simulation. The results showed that using oscillatory excitation gives erroneous results of estimation. Streszczenie. W artykule przedstawiono wyniki pomiarów własności elektrycznych czujnika w przepływomierzu elektromagnetycznym. Wyznaczono dla niego układ zastępczy RC oraz dokonano identyfikacji parametrów. Przebadano również metodą symulacyjną ich wpływ na estymację LS prędkości przepływu w trybie impulsowym. Wyniki dowodzą, że wykorzystanie pobudzania oscylacyjnego jest źródłem błędów estymacji (Budowa schematu zastępczego przetwornika elektromagnetycznego).