Description
The Belimo NFB24-SR is a spring return damper actuator delivering 90 in-lb of torque for accurate modulating airflow control. Operating on AC/DC 24 V with a 2…10 V control signal, it provides dependable fail-safe operation for HVAC damper applications.
Technical Specifications
| Condition |
New/Never Used Surplus |
| Brand |
Belimo |
| Category |
Actuators & Dampers |
| Part Number |
NFB24-SR |
| Subcategory |
Damper Actuators |
| Actuator Type |
Spring return, modulating |
| Nominal Torque |
90 in-lb (10 Nm) |
| Nominal Voltage |
AC/DC 24 V |
| Nominal Frequency |
50/60 Hz |
| Voltage Range |
AC 19.2…28.8 V / DC 21.6…28.8 V |
| Control Signal |
2…10 V (4…20 mA with resistor) |
| Power Consumption (Running) |
3.5 W |
| Power Consumption (Rest) |
2.5 W |
| Transformer Sizing |
6 VA |
| Angle of Rotation |
Adjustable 35…95° |
| Running Time |
95 s / 90° |
| Fail-Safe Running Time |
<20 s @ -20…50°C |
| Electrical Connection |
18 AWG cable, 1 m, 1/2" NPT |
| Degree of Protection |
NEMA 2 |
| Ambient Temperature |
-22…122°F (-30…50°C) |
| Weight |
5.3 lb (2.4 kg) |
Information About NFB24-SR
The NFB24-SR is part of Belimo’s proven spring return damper actuator series designed for reliable airflow modulation in HVAC systems. It combines precise modulating control with a mechanical spring return that drives the damper to a defined safety position during power loss. The actuator supports standard 2…10 V control with optional 4…20 mA input and includes selectable direction of rotation for flexible installation. Its maintenance-free construction and electronic overload protection ensure consistent performance over extended service life.
Key Features
- Spring Return Fail-Safe Operation: Automatically returns the damper to a predefined safety position upon power interruption.
- Modulating Control Capability: Supports 2…10 V control with optional 4…20 mA input for precise airflow regulation.
- Reliable Torque Output: Delivers 90 in-lb of torque suitable for medium-sized air control dampers.
- Adjustable Rotation Range: Mechanical end stops allow angle adjustment from 35° to 95° for application-specific requirements.
- Integrated Position Feedback: Provides 2…10 V feedback for accurate damper position monitoring.
- Quiet Operation: Low motor noise level supports use in occupied and noise-sensitive environments.
- Durable And Protected Design: Double-insulated construction and NEMA 2 rating support dependable HVAC installation.
The NFB24-SR delivers the reliability and precision required for safe and accurate modulating damper control in commercial HVAC systems.
