Belimo LF24-3 Actuator

The Belimo LF24-3 is a high-torque spring return actuator designed for the fail-safe operation of dampers and valves in HVAC systems. Providing 35 in-lb of torque, this 24V motor utilizes a floating control signal to deliver precise positioning for air handling units and zone control applications. Engineered with a brushless DC motor controlled by an Application Specific Integrated Circuit (ASIC), the LF24-3 ensures constant torque and timing regardless of load variations. The mechanical spring return system provides reliable 100% fail-safe closure during power loss, making it a critical component for fire and smoke management or coil protection. This actuator supports easy installation via a universal clamp and includes a manual override crank for field commissioning. With its NEMA 2 (IP54) rated housing, it stands up to rigorous mechanical room environments, ensuring long-term compatibility with standard HVAC control systems and building automation protocols.

• Spring Return Fail-Safe: Ensures dampers return to a predetermined position upon power loss for system safety.
• Floating Control: Allows for incremental positioning and sequence control in complex air distribution setups.
• Universal Compatibility: Mounts directly to damper shafts or valve linkages with a robust, slip-proof clamp.
• Energy Efficiency: Low power consumption during holding and operation reduces the load on 24VAC/DC transformers.
• Internal ASIC Logic: Eliminates the need for limit switches by protecting the motor from stalling at the end of rotation.

How do I change the direction of the spring return on the LF24-3?
The direction of rotation is determined by the orientation of the actuator on the shaft. Flipping the unit over changes the fail-safe direction from clockwise to counter-clockwise.

Can the Belimo LF24-3 be used with both AC and DC power?
Yes, this model is designed to operate on a Class 2 supply of either 24VAC or 24Vdc, providing flexibility for different controller outputs.

What is the typical runtime for this actuator?
The motor typically drives the damper in 40 to 95 seconds, while the spring return provides a fast closure in less than 25 seconds at ambient temperatures.

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.