This Guide helps specifiers select appropriate fluorescent lamp-ballast systems by showing how different ballast types affect lamp life when the lamps may be switched frequently, such as in occupancy sensor applications. The Guide gives the results of NLPIP's testing of seven 2-lamp F32T8 ballasts from three manufacturers. The ballasts included rapid-start electronic ballasts; instant-start electronic ballasts; and rapid-start, energy-efficient magnetic ballasts. Results show that the magnetic ballasts had the lowest system efficacies, and the instant-start electronic ballasts had greater system efficacies than the rapid-start ballasts because of their lower active power. The Guide also describes a new metric, the Rh/Rc ratio, which may be a predictor of lamp mortality. |