INRUSH CURRENT OF LAMP

AbstractLighting systems pass through big change in terms of light source recently. LED replace discharge lamp and thischange represent change of electrical parameters and influence to installations. Lighting systems with dischargelamp use inductive ballasts with choke and starter or electronic ballasts. Lamps with LED use drivers which areswitching sources. The drives include rectifier, high frequency oscillator, transformer and capacitors. Typically,rectifier has impact to distortion of luminaire current and capacitor has impact to inrush current. Over the lastyears, problem increases with inrush current. Public lighting networks reconstruct with LED luminaires. Oftenincrease inrush current and circuit-breaker must be changed for stronger. This change cause increasing ofpayment for energy distribution and sometime is necessary change installation. Aim of this paper is describedifference between luminaires from point of view inrush current. Size and duration of inrush current depends onconstruction of driver and on phase of supply voltage. In paper are analyzed amplitudes, durations and behaviorof electrical parameters various LED luminaires.Key wordsLED, lamp, driver, inrush curren

INFLUENCE DIMING OF LED LAMPS TO ELECTRICAL PARAMETERS

AbstractLighting systems are currently one of the main uses of electricity. The most popular option for reducing ofelectricity consumption is the use of dimming. Dimming is a type of regulation in which we can regulate luminousflux of a lamps and luminaires. This system of regulation is used in the road lighting industry, but also inhouseholds. Dimming allows adaptation of the lighting system according to specific requirements and variousambient conditions such as traffic density, daylight, etc. The regulation of the luminous flux de-pending on thedimming system can affect the electrical parameters of the luminaires such as the power factor. The article dealswith the electrical parameters of luminaires with various lamps at different types of dimming.Key wordsLED, Power factor, total harmonic distortio

INFLUENCE OF ROTATION ANGLE OF LUMINAIRES WITH ASYMMETRICAL LUMINOUS INTENSITY DISTRIBUTION CURVE ON CALCULATED PHOTOMETRIC PARAMETERS

AbstractLighting systems often use square LED panels or spherical luminaires, which may not always have an exactlysymmetrical luminous intensity curve, even if they appear to be symmetrical. A problem with these luminaires canalready arise when measuring luminous intensity distribution curves in a photometric laboratory due to incorrectsymmetry determination. For design reasons, many times it is very complicated or even impossible to determinethe photometric axes of the luminaire in the case of both spherical and square luminaires. This fact may cause adifference in the angle of rotation of the luminaire in light design software and real lighting systems and thus cancause a situation that the lighting system does not meet the requirements of standard STN EN 12464-1. Such asituation is, of course, undesirable and can cause considerable financial losses. Considering the uncertainties ofmeasuring the parameters entering the lighting system calculation and other influences that cause the differencebetween the calculated and measured parameters, it is necessary to oversize the system to a certain extent, butthere is an upper limit defined by Act no. 555/2005 on the energy performance of buildings. This article dealswith the problem that can be caused by an incorrect angle of rotation of the luminaire with an asymmetricalluminous intensity curve when installing the lighting system.Key wordsLED, Lighting design software, luminaire

PHOTOMETRIC PARAMETERS OF LED LUMINAIRES WITH SWITCHABLE CORRELATED COLOUR TEMPERATURE

AbstractAt present, there are lights on the market that are capable of emitting white light with an adjustable correlatedcolor temperature. The advantage of these luminaires is the possibility of changing the correlated colortemperature, for example, due to a change in the function of the room in which they are installed, with noreplacement of the lamps. The disadvantage of such a correlated color temperature setting is that this setting isperformed directly on the luminaire and it is not possible to set the correlated color temperature with the controlsystem. When changing the color temperature, in most cases, it is undesirable to change the other photometricparameters. In this paper, attention is paid to changes of the photometric parameters caused by changing thecorrelated color temperature.Key wordsLED, correlated colour temperature, luminous flux, tunable-whit