Why do I need to set minimum brightness? (ELEGRP Smart Rotary Dimmer Switch: DRS10, DRS30)

This dimmer switch has been set by default to dim a broad range of dimmable LED, CFL, incandescent and halogen lights. However, the dimming range of dimmable CFLs and LEDs can vary from bulb to bulb, some bulbs might flicker at low brightness. Adjusting minimum brightness lets you set the optimal dimming range for your bulbs, which ensures you get the best possible dimming experience.