What is Lamp Lumen Depreciation (LLD)
Lamp lumen depreciation (LLD) is the gradual decrease in the amount of light emitted by a lamp over its lifespan which describes the reduction in lumen output over time. LLD is an important factor to consider when designing lighting systems, estimating the lifespan of lamps, and planning maintenance activities. As lamps age and are used, their lumen output naturally diminishes. This depreciation can be influenced by various factors such as the type of lamp, operating conditions, and environmental factors. LLD is typically expressed as a percentage, representing the proportion of lumen output lost over a specific period.
Lighting professionals can accurately design lighting systems that meet the desired illuminance levels throughout the lamp’s lifespan by considering the rate of lumen depreciation. Additionally, monitoring LLD allows for effective maintenance planning, ensuring that lamps are replaced or retrofitted at the appropriate time to maintain desired lighting levels.