Northwest Energy Efficiency Alliance commissioned a study to delineate the characteristics of 18 dimming systems as part of its Luminaire Level Lighting Control initiative. In theory, adjusting the light level by dimming 15 percent at the control station will have that intended effect (light level or power consumption reduction) at the light source or driver. In practice, this rarely happens. The study found that each ballast’s response to a linear control signal input varied and was not linear. The variances ranged from minor (plus/minus 2 percent) to significant (plus/minus 18 percent). This has implications for utilities in forecasting the anticipated energy savings of a lighting control system.
