Belimo TFB120-S Spring Return Fail-Safe Actuator, 22 in-lb, 100-240VAC

The Belimo TFB120-S is a compact, spring return fail-safe actuator designed for reliable operation in HVAC systems, particularly for damper control in air handling units, ventilation systems, and fire/smoke applications. It delivers 22 in-lb (2.5 Nm) of torque, ensuring precise modulation and fail-safe positioning during power loss via an internal spring mechanism that returns the damper to a safe position. Key features include a brushless DC motor for energy efficiency, manual override capability, and an integrated auxiliary switch for status feedback. Advantages over similar products include its wide voltage range (100-240VAC) for global compatibility, low power consumption (2W running, 1W holding), and robust construction rated for ambient temperatures from -22°F to 122°F. Benefits include enhanced system reliability, reduced maintenance, and easy installation with a universal clamp design. Drawbacks may include a fixed 75-second runtime, which could be slower than non-spring return models, and it's best suited for smaller dampers up to 5 sq ft. This actuator excels in building automation, providing fail-safe performance in critical environments like hospitals and commercial buildings, outperforming basic actuators in energy efficiency and durability.