Belimo NFB24-S

Damper Actuator, 90 in-lb [10 Nm], Spring return, AC/DC 24 V, On/Off, 2 x SPDT

Application

For On/Off, fail-safe control of dampers in HVAC systems. Actuator sizing should be done in accordance with the damper manufacturer?s specifications. Control is On/Off from an auxiliary contact, or a manual switch. The actuator is mounted directly to a damper shaft up to 1.05? in diameter by means of its universal clamp. A crank arm and several mounting brackets are available for applications where the actuator cannot be direct coupled to the damper shaft.

Operation

The NFB and NFX series actuators provide true spring return operation for reliable failsafe application and positive close off on air tight dampers. The spring return system provides constant torque to the damper with, and without, power applied to the actuator.

The NFB and NFX series provides 95° of rotation and is provided with a graduated position indicator showing 0° to 95°.

The actuator may be stalled anywhere in its normal rotation without the need of mechanical end switches.

The NFB24-S and NFX24-S versions are provided with two built-in auxiliary switches.These SPDT switches are provided for safety interfacing or signaling, for example, for fan start-up. The switching function at the fail-safe position is fixed at +10°, the other switch function is adjustable between +10° to +90°. The NFB24, NFB24-S, NFX24 and NFX24-S actuator is shipped at +5° (5° from full fail-safe) to provide automatic compression against damper gaskets for tight shut-off.

Features:

• Cut labor costs with simple direct coupling.
• True mechanical spring return - the most reliable fail-safe.
• Mount for clockwise or counterclockwise fail-safe.
• Check damper position easily with clear position indicator.
• Don’t worry about actuator burn-out. Belimo is overload-proof throughout rotation.
• Built-in mechanical stop to adjust angle of rotation.
• Manual override crank speeds installation
• Need to change control direction? Do it easily with a simple switch (modulating actuators).
• Incorporated breather membrane optimizes performance in harsh airstream environments.
• Built-in auxiliary switches are easy to use, offers feedback or signal for additional device (-S models).
• Microprocessor-controlled brushless DC motor increases actuator life span and reliability, provides constant running time (modulating actuators).
• Rugged metal on plastic housing withstands rough handling in the mechanical room.
• Standard 3 ft. appliance rated cable and conduit connector eases installation.
• Added flexibility to select clamp, electrical connection, and running time to fit your specific application with Belimo?s customized line of actuators (NFX).

Attributes