Belimo LF120-S Actuator

The Belimo LF120-S Actuator is a 120V AC spring-return Fail-Safe actuator engineered for HVAC damper control and valve linkage applications. Providing 35 in-lb (4 Nm) of torque, this unit is a direct replacement for the legacy MA-7101-500, ensuring seamless integration into existing on/off damper control systems without extensive mounting modifications. Designed for reliability in harsh mechanical environments, the LF120-S features a brushless motor controlled by a microprocessor for precision operation and overload protection. The integrated SPDT auxiliary switch provides essential feedback for end-stop verification or interlock sequencing. Its compact NEMA 2 housing allows for installation in tight mechanical plenums, while the mechanical position indicator provides immediate visual confirmation of damper state. This fail-safe actuator ensures the system returns to the safety position during a power loss, maintaining critical airflow control in commercial air handling units.

• Universal Compatibility: Direct replacement for MA-7101-500 simplifies retrofitting in legacy control loops.
• Reliable Fail-Safe: Mechanical spring-return ensures positive closure or opening during power interruptions.
• Integrated Sequencing: Built-in SPDT auxiliary switch allows for easy signaling to fans or secondary controllers.
• Enhanced Durability: Brushless DC motor technology reduces wear and eliminates the need for limit switches.
• Flexible Mounting: Reversible rotation logic allows for clockwise or counter-clockwise fail-safe positioning.

How do I adjust the auxiliary switch on the LF120-S?
The integrated SPDT switch is fixed at 10° to provide consistent end-stop signaling, reducing commissioning time in the field.

Can this actuator be used in outdoor environments?
The LF120-S features a NEMA 2/IP54 rated enclosure, making it suitable for protected indoor environments or within weather-shielded enclosures.

What is the typical run time for this spring-return actuator?
This unit typically achieves a motor run time of 40 to 75 seconds, with a spring-return timing of less than 25 seconds at ambient temperature.

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.