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Photometry of LED sources

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In this article each luminous intensity curve of LED sources, measured in different photometric distances were compared. It also compares the luminous efficacy, luminance and illuminance provided with LED sources compared to fluorescent sources. It also compares the energy demands of different sources to achieve equivalent illumination. Streszczenie. W artykule porównano rozsyły światłości diod świecących, mierzone w różnych odległościach fotometrowania. Również porównano skuteczności świetlne, luminancje i natężenia oświetlenia uzyskane od źródeł LED w odniesieniu do wyników uzyskanych dla świetlówek. Również porównano charakterystyki energetyczne różnych źródeł w celu osiągnięcia równoważnego natężenia oświetlenia. (Fotometrowanie źródeł LED) Keywords: LED sources, photometry, illuminance. Słowa kluczowe: źródła LED, fotometria, natężenia oświetlenia. Introduction In the context of Regulation No. 244/2009 of 18th March 2009 of the European Commission based on the directive of the European Parliament and Council Directive 2005/32/EC relating to eco-design requirements for omni-directional light sources for households [4] in the EU since 1st September 2009 gradually the import and production of incandescent light sources according to their power are banned, until they are completely stopped on the 1st September 2016. By this step the European Commission plans, provided on the substitution of incandescent light sources with compact fluorescent lamps, to save 40 TWh of electrical power annually (equivalent to average annual electrical energy consumption of 11 million European households in 2008) [1,7]. Efficiency of electrical energy conversion of the first banned (but most effective) 100 W incandescent light source is with the luminous flux Φ = 1350 lm, approximately 2 % (derived from the maximum theoretical efficacy of 683 lm·W-1). Therefore, they are gradually replaced by more efficient light sources, whether based on[...]

Comparison of Electric and Radiometric Methods for Liquid Dielectric Diagnostic DOI:10.15199/48.2019.06.04

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This paper is aimed at creating a comprehensive methodology for comparison the laboratory measured quality of liquid dielectrics by electrical and radiometric or photometric methods. Standard electric parameters diagnostic could be divided on partial discharge measurement according by IEC 60270; DC electric parameters (EN 60247); dissipation factor measurement (EN 61620) and for breakdown voltage measurement can be used the procedure according the standard EN 60156. Conversely radiometric measurement for determining liquid quality used only as an alternative method. An exception is the testing of plant oils intended for food industry. In this case, the oil quality, type of oil and the presence of other substances are determined by optical and radiometric methods. Liquid insulators used in power engineering and energetic are most often tested according to ISO 2049 and EN 60422. The ASTM scale according to standard ISO 2049 for the determination of color of insulating transformer oil or other petroleum product. However, very accurate measuring technology is nowadays offered by optical and light laboratories. The result may be spectral transmittance or absorption measurements in visible, IR and UV area of spectra. Especially the UV area has proved to be very sensitive to small differences in the change in the quality of liquid dielectrics. Also, luminescence measurement is a very interesting method for measuring the quality of liquid dielectrics, thermal degradation and the presence of additives and water content. Liquid dielectrics are used in the energetic and power engineering as insulating and heat transfer medium. Insulating oils are therefore an irreplaceable substance in many energetic systems and equipments such as transformers, some bushings, capacitors, oil cables or power switches and circuit breakers. The quality of liquid dielectrics greatly affects the reliability of the operation of these equipments. For this [...]

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