J. Hoja, G. Lentka
The paper deals with problems of very high impedance (| Z | < 10 GΩ) measurements in a wide frequency range (10 -5... 10 6 Hz). The measurements are aimed to identify electrical parameters of different anti-corrosion coatings. The construction of the measuring system designed for monitoring the anti-corrosion coatings effectiveness on various types of technical objects is presented. The circuit solutions analysed refer, in particular, to the input adapter, the measuring signal generator, and the phase-sensitive detector. The test results of the whole measuring path are shown and some...
XVI IMEKO World Congress
· TC4
· 2000
· Download
N. Hlupic, M. Kresic, I. Lenicek
Two methods, one approximate and one theoretically (mathematically) exact, for calculation of parameters of measured low frequency sinusoidal signal are thoroughly studied and compared. Both methods perform sampling of measured signal by HP 3458A Digital Multimeter in DC mode in order to achieve the best possible accuracy. Comparison was made firstly on calculated, ideal sinusoid (computer simulation) what has shown us theoretical limits of accuracy due to calculating inaccuracy and approximations. Then a series of measurements in real, laboratory conditions was made to confirm or refute...
XVI IMEKO World Congress
· TC4
· 2000
· Download
I.A. Henderson, L. Jackowska-Strumillo, J. McGhee
The transfer of information theory from data communications to digital measurement in the form of the coding theorems, descriptive languages and data patterns, has provided new digital signals. In this paper, shift keyed symbols are used to design Symbolic Addition (SA), Phase Shift Keyed (PSK) and Frequency Shift Keyed (FSK) signals. These allow different aspects of a frequency response to be investigated with one signal and one experiment. Symmetrical versions of these signals allow a set of Multifrequency Identification Patterns (MIPs) which can capture and monitor different...
XVI IMEKO World Congress
· TC4
· 2000
· Download
J. Gronczynski, J. Mroczka
This paper presents a method of the measurement of resistance that can be used in a simple microcontroller systems. A direct analog-to-digital conversion (without the measurement of any additional values like a voltage or current) was based on the charge balancing scheme. The whole measurement is divided into two stages. The final result is achieved by computing the difference between them. It makes it possible to eliminate theoretically influences of many factors evoking errors such as long time instability and accuracy of a voltage reference source, influences of supply voltage or offset...
XVI IMEKO World Congress
· TC4
· 2000
· Download
F. Galliana, G. Boella
Experimental results concerning the behaviour of some high value resistors versus applied dc voltage are given. The measurements have been carried out at IEN on typical standard resistors, normally available in National and secondary laboratories, in the field 10 MΩ ÷ 1 TΩ by means of the measurement systems described in [1, 2]. The measurement results, with which we tried to determine the voltage coefficients, showed for most of the measured resistors a behaviour versus voltage that is the addition of linear and quadratic components.
XVI IMEKO World Congress
· TC4
· 2000
· Download
M.T. Galewski, M. Woloszyk, S. Wojtas
Paper proposed concerns measurement of inductance in time domain. Authors propose new notions: ‘impulse resistance’, impulse inductance’ and ‘impulse effectiveness of earthing’. The principle of the measuring method is presented, its advantages in respect to frequency methods are discussed. This paper is a continuation of our work on measurements of features of earthing in time domain, with short current impulses.
XVI IMEKO World Congress
· TC4
· 2000
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K. Fujino, K. Fukuo
A compact, low cost harmonics measurement equipment, harmonics monitorTM, has been developed using a DSP based mixed signal ASIC. Each effective current harmonics from the basic frequency up to the 19 th order harmonics and the total harmonics distortion ratio can be obtained in real time. In stead of using a conventional FFT method a 6 th order, digital IIR filtering method was used for the accurate measurement. It allowed the computation to be in real time and the configuration of the main circuitry to be simplified into a single chip, thereby reducing the system cost. To compensate gain...
XVI IMEKO World Congress
· TC4
· 2000
· Download
C. Fosalau, M. Cretu, O. Postolache
The paper presents an instrument designed to measure the period of signal buried in noise and having a high degree of distortions. It works as a virtual instrument implemented on a personal computer that receives the digitized signal from a digital acquisition card or from a digital oscilloscope through the GPIB interface. Its operation principle is based on a new algorithm developed for assessing the period of the input sampled signal by comparing a witness segment of samples with the rest of the samples that compose the signal, till they overlap the best. The method, as well as the...
XVI IMEKO World Congress
· TC4
· 2000
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B. Fock
For the calibration of power meters, it is preferred to use virtual sources that supply voltage and current at their outputs with high accuracy and in a manner that the phase angle between the two electric quantities can be set to the desired value. Due to the direct calibration procedure, these sources are required to be stable and accurate as well. As a transformer is included in the voltage- and current amplification circuits, the inherent nonlinearity of transformers and the handling of problems due to the effect of diffuse parameters (stability, accuracy and distortion) become of great...
XVI IMEKO World Congress
· TC4
· 2000
· Download
L. Ferrigno, C. Liguori, A. Pietrosanto
In the paper a new method for the measurement of R , L , C parameters under non-sinusoidal condition is proposed. The measurement procedure, starting from the consideration that for a non-linear SISO system the discrete transfer function H(z) functionally depends on the applied input, uses the estimated z parameters to obtain the best estimate of the equivalent circuit R , L , C parameters of first and second order systems. The method is implemented by a virtual instrument based on IEEE-1155 and IEEE-488 measurement systems. The realized instrument is vatidated with reference to many...
XVI IMEKO World Congress
· TC4
· 2000
· Download