Systems Comparison and Performance Luminaire light output and ballast input wattage are affected by the thermal operating point of the lamps. This, coupled with the total lumens available, the ability of the ballast to deliver lumens, plus the optical efficiency of the luminaire itself, determines the final lumen output of the luminaire. Once photometry was completed, the relative light output compared to the base system was determined. Efficiency - Using relative light output and input watts, an efficiency rating was determined compared to the base system. This evaluation of lumens per watt provides a useful comparison since all components are evaluated to the base system.
System lumens - System lumens represents total rated lumens of the lamps installed.
Luminaire efficiency - The photometric measurement of luminaire efficiency is the percentage of lumens leaving the luminaire compared to rated lumens installed. In this report it is an indicator of the gains made through the reduction of lamp diameter in this particular luminaire. Input power was 88 watts. Present day fluorescent lighting efficacies have been improved by phosphor technology that emits light in the red,blue and green portions of the visible spectrum. These new phosphors can withstand higher power loading and exhibit less depreciation over time compared to standard colour halophospates.