2CSM229921R1341

The ABB TL1 Twilight Switch (2CSM229921R1341) is an automatic light-sensitive switching device designed to control electrical lighting based on ambient illumination. It operates with an external light sensor included in the package and provides adjustable switching thresholds from 2 to 200 lux. The device automatically switches connected lighting circuits ON when the ambient light falls below the selected threshold and OFF when the light rises above the configured level.

The TL1 features an adjustable light-sensitivity setting, a switching delay of approximately 23 seconds to help prevent unwanted switching caused by brief changes in light intensity, and LED indicators for setpoint and contact status. It operates on a 110–230 V AC supply and is designed for compact, single-module DIN-rail installation in electrical distribution boards. Typical applications include garden lighting, parking areas, building entrances, outdoor lighting and other installations requiring automatic dusk-to-dawn lighting control.