Belimo TFB120-S Actuator

The Belimo TFB120-S Actuator is a spring return damper actuator designed for reliable on/off control in HVAC systems. Delivering 22 in-lb torque, this unit is engineered for small-to-medium dampers and control valves requiring a fail-safe position during power loss. Operating on a 120Vac power supply, it features a rugged NEMA 2 housing for demanding mechanical environments. The integrated auxiliary switch provides essential position feedback for building automation systems and interlocking circuits. With a mechanical travel time of less than 75 seconds and a spring return time of under 25 seconds, the TFB120-S ensures rapid response. Its universal bolt-on design simplifies field installation on shafts ranging from 1/4" to 1/2" diameter, making it a staple for contractors maintaining HVAC air handlers and economizers. The brushless DC motor technology eliminates contact wear, ensuring consistent timing and stall-proof performance without the need for limit switches.

• Fail-Safe Reliability: Mechanical spring return ensures the damper or valve returns to a safe position during emergency power interruptions.
• Integrated Feedback: One built-in SPDT auxiliary switch allows for easy monitoring of actuator status without external sensors.
• Quiet Operation: Precision gear train maintains a low noise floor, ideal for noise-sensitive commercial installations.
• Easy Installation: Features a reversible mounting design and a simple manual override for commissioning and troubleshooting.
• Robust Construction: UL listed and rated for varied ambient temperatures, providing dependable service in mechanical rooms.

How do I wire the TFB120-S for 120V operation?
Connect the core line voltage to the black and white leads. The actuator remains energized to hold position and springs back when the 120Vac signal is removed.

Can the auxiliary switch be adjusted in the field?
The switch is factory-set to trip at 10 degrees, providing a standard end-stop signal for dry contact loops.

What is the maximum damper area this 22 in-lb actuator can handle?
It typically supports dampers up to 4 square feet, though high-pressure seals or high-velocity airflow may require higher torque ratings.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.