Belimo FSNF120 Fire Smoke Damper Actuator in-lb Spring Return - 120V 70

The Belimo FSNF120 is a spring-return fire and smoke damper actuator designed for critical life safety applications in commercial HVAC systems. This fail-safe actuator provides reliable operation of smoke and combination fire/smoke dampers in ventilation and air-conditioning systems, meeting stringent UL555 and UL555S requirements.

Key Performance Features:

• 70 in-lb (8 Nm) torque for positive damper control and sealing
• 15-second cycle time for rapid response in emergency situations
• Spring return fail-safe operation automatically closes damper upon power loss
• Rated for 350°F (177°C) continuous operation for 30 minutes
• On/Off control with AC 120V nominal voltage (96-132V range)
• 95-degree rotation angle with clockwise/counterclockwise mounting flexibility

Construction and Mounting:

• Galvanized steel housing with permanently lubricated steel gears for durability
• Cold-weld clamp mounting system fits 3/8" to 1.05" round shafts without crushing hollow shafts
• Anti-rotation bracket mounting for secure installation
• 1/2" NPT threaded conduit connection with 1-meter cable included
• UL Listed (File XAPX.E108966) and AMCA 520 certified

Electrical Specifications:

• Power consumption: 27 VA running, 9 VA holding, 55 VA at end stop
• 50/60 Hz frequency with 0.5A slow blow fuse protection recommended
• 3.2A inrush current with double insulated construction
• Operating temperature range: 32°F to 122°F (0°C to 50°C) ambient

The FSNF120 mounts in its fail-safe position with damper blades closed. Upon power application, the internal spring tensions as the actuator drives the damper open. If power is interrupted by fire alarm or smoke detection systems, the spring automatically returns the damper to the closed position, containing smoke and fire spread. This actuator is engineered for 20,000 cycle life expectancy and requires no maintenance during normal operation.