ANSI IESNA LM-73-2004 pdf download IESNA Guide forPhotometric Testing ofEntertainment Lighting Luminaires Using Incandescent Filament Lamps orHigh Intensity Discharge Lamps
2.2 Ambient Temperatures The ambient temperature of the photometric labora- tory shall be maintained at 25°C ±5°C (77°F ±9°F).
2.3 Test Lamp Selection and Seasoning Test lamps shall be selected for conformance to man- ufacturer’s design dimensions and constructions. The lamps shall be seasoned in accordance with LM-54, IESNA Guide to Lamp Seasoning, 3 so that their char- acteristics will be nearly constant during the test.
2.4 Test Lamp Operation Stable lamp operation is necessary. Incandescent fila- ment lamps shall be operated at a constant current corresponding to the current required to produce approximately 75 percent of rated lumen output. A stabilization time of 10 minutes is usually sufficient for incandescent lamps. Discharge lamps shall be operat- ed at their rated wattage and shall be run until their light output is stable.
4 Identical operating conditions must be used for the luminaire test and for lamp calibration. If absolute measurements are required, incandescent lamps (including tungsten-halogen), shall be operat- ed at full rated voltage, and HID lamps shall be oper- ated at full rated wattage. As an alternative method, for situations where lamp wattage cannot be conveniently measured, discharge lamps may be operated on the manufacturer’s speci- fied ballast and at rated voltage for both the luminaire test and lamp calibration. This technique must be noted on the test report, and may produce results slightly different from those obtained when stabiliza- tion is based on lamp wattage.
2.5 Test Distance The distance between the luminaire and the detector shall be sufficiently large so that the inverse square law (ISL) can be applied at this and all greater distances. This minimum test distance shall be deter- mined by taking illuminance readings over a series of increasing distances and then computing intensities using the ISL. Beyond a certain distance, the com- puted intensities will become constant. If it is more appropriate for the luminaire and its typical applica- tion, measurement can be made at a lesser distance; however, the limitations on the ISL shall be stated. Note: The minimum distance where the ISL applies to entertainment luminaires is often much greater than “five times effective aperture,” the common minimum distance suggested for general lighting luminaires.