Belimo NFU-S2 Safe Damper Actuator

Belimo NFU-S2 Safe Damper Actuator is a fail-safe rotary damper actuator designed for HVAC dampers, delivering reliable spring-return closure when power is removed and opening when energized. It provides 10 N·m of torque and accepts an AC supply from 24 to 240 V or DC from 24 to 125 V to drive damper positioning, with the travel completing in about 75 seconds for a full open/close cycle. The unit includes two SPDT end switches for position feedback and is rated IP54 for protection against dust and water ingress. The damper crank arm accepts a slot width of 8.2 mm and supports a clamping range of Ø10–18 mm, with a 63 mm hand crank option available for manual operation on compatible dampers such as BFL, BFN, BFA, BEN, and BEE. This Belimo actuator belongs to the fail-safe family engineered for fire and smoke damper applications, offering repeatable operation, broad voltage compatibility, and straightforward mounting for retrofit or new installations.