Belimo FSTF120-S Fire and Smoke Damper Actuator 18 in-lb Spring Return 120V

The Belimo FSTF120-S is a spring return fire and smoke damper actuator designed for life safety applications in commercial HVAC systems. This UL-listed actuator provides reliable fail-safe operation for smoke and combination fire/smoke dampers in ventilation and air-conditioning systems.

Key Specifications:

• Torque: 18 in-lb (2 Nm) - suitable for dampers up to 1.5 sq. ft. at 2000 fpm air velocity
• Power Supply: 120 VAC, ±10%, 50/60 Hz, 5 VA consumption
• Control Type: On/Off, two-position control
• Spring Return: Fail-safe operation with less than 25 second spring return time
• Motor Running Time: 75 seconds at 250°F (121°C)
• Auxiliary Switches: 2x SPST, 3A (0.5A inductive) @ 120/250V - one fixed at 10°, one fixed at 80°

Installation Features:

• Shaft Compatibility: Fits 1/4" to 1/2" round shafts, centers on 1/2"
• Rotation Angle: 95° with reversible direction via CW/CCW mounting
• Electrical Connection: 3-foot wire leads, 18 AWG with 1/2" NPT conduit connection
• Enclosure Rating: NEMA 2, IP42, UL Enclosure Type 2
• Operating Temperature: 32°F to 122°F (0°C to 50°C) normal; rated for 250°F (121°C) for 30 minutes during fire event

Safety Certifications: UL555 and UL555S listed when tested as an assembly with approved dampers. Meets requirements for fire and smoke damper applications with 20,000 cycle life expectancy per UL555S standards.

The FSTF120-S includes auxiliary switches for status indication and system integration. Compatible with Belimo's complete line of mounting brackets, crank arms, and accessories for flexible installation options. Backed by Belimo's 5-year warranty for long-term reliability in critical life safety applications.