The Helios Fans ESE 2.5 is a compact electronic speed controller designed for smooth, stepless control of AC fans. Utilizing phase-angle triac technology, it allows manual adjustment of motor voltage from 230 VAC down to 60 VAC via a rotary knob, which also includes an integrated OFF position. The device features an internal trimmer to set the minimum speed limit. It includes both regulated and unregulated switching outputs and is suitable for installation in standard switch and distribution cabinets using a 35 mm DIN rail. Operating frequency is 50/60 Hz, with an IP30 protection rating.