Belimo EFB120-S N4 Damper Actuator Spring Return

The Belimo EFB120-S N4 Damper Actuator Spring Return delivers 270 in-lb (30 Nm) of direct-coupled torque for reliable two-position damper control in HVAC systems, with a true spring-return mechanism that moves the damper to its fail-safe position when power is removed. It operates from AC power across 100–240 V and uses a two-position On/Off signal to drive the damper to fully open or closed, while providing two SPDT auxiliary switches for end-of-travel or status signaling. The unit is built with a NEMA 4 enclosure, enabling outdoor and harsh-environment installations, and is part of Belimo’s EFB120-S N4 family designed for outdoor-protected, spring-return applications. This actuator combines rugged protection with straightforward control, making it a solid choice for dampers where immediate power loss should drive the damper to a safe, predefined position.