https://etalpykla.vilniustech.lt/handle/123456789/157279 Sat, 11 Apr 2026 18:02:56 GMT 2026-04-11T18:02:56Z https://etalpykla.vilniustech.lt/handle/123456789/157400 Earthing effective length for low and high amplitudes of lightning impulse currents Wojtas, Stanisław Earthings of the electrical power systems can achieve wide sizes. Due to equipotential bondings and a presence of main equipotential bar the earthing system can be connected even to a power transformer neutral point. Evaluation of such wide earthings for lightning protection purposes can not be easy to perform because only a part of the earthing system should be taken into account. This useful part of the earthing is described as its effective length. The paper deals with a method of effective length calculations and in order to explain the notion computer simulations and measurements of a model as well as a real earthing have been performed using impulses of 1, 4 and 10 µs front times. A good convergence investigation results have been obtained. Sun, 01 Jan 2012 00:00:00 GMT https://etalpykla.vilniustech.lt/handle/123456789/157400 2012-01-01T00:00:00Z https://etalpykla.vilniustech.lt/handle/123456789/157399 Electric system and electronic device common surge impedance for surge excitation Wiater, Jarosław Impedance for lightning conditions is different in respect to static one. Fast rising surges forces impedance rise. This paper will present a surge impedance measurement results for residential devices. Measurements were taken during normal work of hand drill, television set, radio, bulb 100W,satellite receiver set laser printer, desktop personal computer. Voltage-current surges (1,2/50 µs - 8/20 µs) were used as an excitation. Surges were putted on power supply line which powers devices. Sun, 01 Jan 2012 00:00:00 GMT https://etalpykla.vilniustech.lt/handle/123456789/157399 2012-01-01T00:00:00Z https://etalpykla.vilniustech.lt/handle/123456789/157398 Overvoltages at LAN network during high voltage surge excitation Wiater, Jarosław This paper presents disturbances measurement results inside the computer network during surge flow in lightning protection system (LPS). Surge was produced by high voltage generator fully isolated from building supply line where computer network LAN (Local Area Networks) exists. Used generator works with nominal capacitor voltage level equal 52 kV. It produced 2,16 kA 10/75 µs current surges. Sun, 01 Jan 2012 00:00:00 GMT https://etalpykla.vilniustech.lt/handle/123456789/157398 2012-01-01T00:00:00Z https://etalpykla.vilniustech.lt/handle/123456789/157397 Analysis of errors caused by input channels amplitude discrepancies in time domain EMI measuring system Valky, Gabriel; Kamensky, Miroslav; Kovac, Karol In this document properties of signal spectrum measured by time domain EMI multi resolution device are discussed with focus on elements of system that influence its dynamic range. Errors being analyzed are introduced by circuits used in parallel input channels typical for multi resolution analog-to-digital (AD) converter system. In ideal case all signal paths should have flat frequency response and similar offset of used AD converters but real systems have not. Sun, 01 Jan 2012 00:00:00 GMT https://etalpykla.vilniustech.lt/handle/123456789/157397 2012-01-01T00:00:00Z