ABB 64851 U-500 — 2-wire connection (neutral conductor not required) Neutral conductor optionally connectable (recommended for the connection of low loads < 10 W/VA). Touch dimmer for switching lighting systems. Operation in 1gang 2way installations via push switch-unit for combination with flush-mounted units. Operation also possible via conventional push buttons (2020 US, 2021/6 UK). Optimised for dimming of retrofit LED lamps (LEDi). For dimmable Retrofit-LEDs (LEDi). For dimmable Retrofit-LEDs (LEDi) with conventional or electronic transformers. For incandescent lamps, 230 V tungsten halogen lamps, low-voltage halogen lamps with conventional or electronic transformers and dimmable energy-saving halogen lamps. Mix operaton of LEDi with conventional loads possible. With manually adjustable operating mode: trailing / leading edge control. With adjustable minimum brightness. With light-level memory and minimum brightness memory. Low-noise level by MOSFET transistors. With electronic short-circuit protection. With electronic overload protection. Without control cover. For control element flex, 1gang, 64711. For control element flex, 2gang, 64721. For control element flex, 1gang, wireless, 62711-WL. For control element flex, 2gang, wireless, 62721-WL. For Busch-Watchdog 180 flex sensors, wireless, 6276x-.-WL. Rated power: 3-240 VA (LEDi).