Light sources may be evaluated based upon several photometric characteristics including luminous flux, luminous intensity, and spectral distribution. Luminous flux (measured in lumens) may be the total light production of a source and is the basic photometric quantity from which other quantities for example luminous intensity are defined when it comes to. The spectral distribution or spectral composition details the relative quantity of each wavelength, or color, which a source of light is composed of.
Values to the luminous flux of each and every LED product are obtained by measuring luminous intensity distribution using Goniophotometer. The goniophotometer includes a photometer placed on a motor-driven arm that rotates in plane as well as a set distance relative to the lighting source being tested. Lux (lm/m²) values at every angular step are logged into our custom application in synchronization with the motor actuation.
The scanning resolution of the test setup is a 1.8° longitudinal (vertical) and 90° lateral (horizontal) grid. The fine angle resolution from the vertical plane was used to lower the impact of any non-systematic measurement error by calculating over a large data set. A 90° lateral resolution was sufficient for testing luminaires built to provide symmetrical distribution. As our testing is centered on indoor LED lighting fixtures, light is usually emitted in the forward direction with out light emission was blocked from the test apparatus. To prevent ambient light and temperature variation effecting the outcome, the exam was conducted within a dark and temperature controlled room.
The LED Testing thus permits us to appraise the light production of an LED along a circumferential area on two transverse planes. A procedure of interpolation and integration based on our measurements is calculated, from which the entire light output over a spherical surface, independent of measuring distance, i.e. the luminous flux is obtained. Note: that only one of many two axis are show within the video and also the video is sped up 256 times.
220-240 VAC light fittings are powered from an (Australian standard) AC wall socket. 110-120 VAC lights are supplied coming from a 240 – 115V Isolated Stepdown Transformer. The conventional light fitting installed on our Spectroradiometer is a bayonet fitting. Bulbs with non-B22 fittings are connected via B22 base adaptors.
All MR16 lighting is connected right to an OSRAM Redback 20-60 Watt electronic transformer via standard cables approximately 240 mm in size in order to minimise voltage drop from your 12 VAC transformer output. The OSRAM Redback transformer was selected since the standard transformer for the test procedure according to it’s popular utilize in Australian homes along with the assumption the user would desire to minimise cost by retrofitting LED lights on their existing halogen transformer rather than dexfpky08 the additional cost for any specific transformer recommended from the LED light manufacturer. It should therefore be noted that this measurements gathered for those MR16 lights is specific on the electronic transformer used and satisfaction could differ using other transformers.
Exactly the same power supply configurations were used to examine lumen output, intensity distribution, wattage, power factor, temperature and dimming.