Description
The Belimo NMB24-SR is a non fail-safe damper actuator designed to deliver 90 in-lb (10 Nm) of torque for precise modulating airflow control. It operates on AC/DC 24 V power and supports a 2–10 V control signal with integrated position feedback for accurate damper positioning.
Technical Specifications
| Condition |
New/Never Used Surplus |
| Brand |
Belimo |
| Category |
Dampers & Actuators |
| Part Number |
NMB24-SR |
| Subcategory |
Damper Actuators |
| 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 |
| Power Consumption (Operation) |
1.5 W |
| Power Consumption (Rest) |
0.4 W |
| Transformer Sizing |
5 VA |
| Control Signal |
2…10 V (4…20 mA with resistor) |
| Input Impedance |
100 kΩ (2…10 V), 500 Ω (4…20 mA) |
| Position Feedback |
2…10 V |
| Torque Output |
90 in-lb (10 Nm) |
| Angle of Rotation |
Max. 95°, adjustable |
| Running Time (Motor) |
95 s / 90° |
| Electrical Connection |
18 AWG plenum cable, 1/2" NPT |
| Degree of Protection |
IP54 / NEMA 2 |
| Noise Level |
45 dB(A) |
| Ambient Temperature |
-30…50°C |
| Weight |
2.2 lb (1.0 kg) |
Information About NMB24-SR
The NMB24-SR is part of Belimo’s NMB series of compact non fail-safe damper actuators developed for reliable modulating airflow control in commercial HVAC systems. It features electronic overload protection throughout the full 0–95° rotation range to protect internal components and maintain consistent torque output. The actuator supports standard 2…10 V control and can be adapted for 4…20 mA operation using an external resistor, allowing compatibility with a wide range of building automation systems. Its plenum-rated cabling, selectable direction of motion, and maintenance-free design support efficient installation and long-term dependable operation.
Key Features
- Non Fail-Safe Operation: Provides powered damper positioning without spring return for applications where fail-safe action is not required.
- 10 Nm Constant Torque Output: Delivers stable 90 in-lb torque for accurate control of small to medium air dampers.
- Modulating Control Interface: Accepts a 2…10 V control signal with optional 4…20 mA configuration for precise proportional airflow regulation.
- Electronic Overload Protection: Protects the actuator across the entire rotation range to prevent damage from obstruction or excessive load.
- Integrated Position Feedback: Supplies a 2…10 V feedback signal for continuous damper position monitoring and closed-loop control.
- Selectable Direction Of Motion: Motor rotation direction can be configured via an onboard switch to match installation requirements.
- Manual Override Push Button: Allows local damper positioning during commissioning, testing, or maintenance without tools.
The NMB24-SR delivers the reliability and precision required for accurate modulating airflow control in non fail-safe HVAC damper applications.
