Belimo NF24A-SZ - rotary actuator with spring return

Belimo NF24A-SZ – rotary actuator with safety function

The actuator positions dampers in stationary heating, ventilation and air conditioning systems. During operation, the Y control signal moves the damper and tensions the return spring. When the power supply is interrupted, the spring moves the damper to the safety position.

Key features and specifications

• Motor and safety function torque: 10 Nm.
• Rated voltage: AC/DC 24 V; voltage range: AC 19.2...28.8 V / DC 21.6...28.8 V.
• Y control range: 0.5...10 V; U position feedback signal: 0.5...10 V.
• Motor running time: 150 s / 90°; safety function running time: <20 s @ -20...50°C, <60 s @ -30°C.
• Rotation angle: max. 95°; adjustment by mechanical stops.
• Universal shaft clamp for 10...25.4 mm; manual adjustment using a crank and locking switch.
• Power and control connection: 1 m cable, 4x 0.75 mm².
• Power consumption: 3.5 W during movement and 2.5 W at rest; power rating for cable sizing: 5.5 VA.
• Protection rating: IP54; ambient temperature: -30...50°C [-22...122°F].

The motor direction is selected using the L/R switch, while the safety function rotation direction is selected by the L/R mounting method. The documentation specifies air dampers with an area of up to approximately 2 m².