Pay safe and fast with:
The Belimo NF24A-SR is a modulating valve actuator with spring return designed for continuous positioning of air damper sections up to approximately 2 m². The actuator is controlled by a 2-10 V signal and also provides a feedback signal (SR) of 2-10 V back to the controller or cascade control system. Based on an external measurement signal—for instance, from a sensor monitoring a relevant parameter such as temperature, pressure or air quality—a control signal is generated to instruct the Belimo motor to adjust the damper position. In the event of a power failure, the damper automatically and independently returns to the safe position, powered by spring energy. The actuator delivers a torque of 10 Nm, making it suitable for medium-sized damper assemblies in central air handling units. The position accuracy is ±5% over the entire control range, and the motor achieves a 90° rotation in 150 seconds. The spring return brings the damper back within less than 20 seconds. The standby power consumption is 2.5 W, and the noise level is only 40 dB(A).
The actuator mounts directly onto the damper shaft using the supplied universal clamp ring, suitable for shaft diameters from 10 to 25.4 mm. The shaft must be at least 85 mm long and extend at least 15 mm. An included anti-rotation device prevents the actuator from turning with the shaft. The motor’s direction of movement is set via a switch; the spring return direction is determined by the mounting orientation (L/R). The rotation angle is mechanically adjustable starting from 33% in increments of 2.5% up to a maximum of 95°. For manual operation, a hand crank is provided that allows locking the damper in any position. Electrical connection is made via a fixed 1-metre cable with four cores of 0.75 mm². The actuator is maintenance-free and suitable for modulating positioning of medium-sized air damper sections in central air handling units, VAV ducts, mixing dampers and emergency ventilation dampers in commercial buildings and industrial HVAC installations.
| Brand | Belimo |
| Category | Belimo valve drive |
| GTIN | 7630498112843 |
| Manufacturer's item number | NF24A-SR |
| Article number | 23010060 |
| Category code | 101 |
| Suitable for air accessory | Yes |
| Supply voltage | 24 V AC/DC |
| Control signal | Other |
| Energy consumption in operation | 3.5 W |
| Energy consumption at rest | 2.5 W |
| Model | Rotating |
| Regulation type on/off | No |
| Regulation type modulating | Yes |
| Regulation type splitrange | No |
| Connection cable length | 1 m |
| Transmission | With cogwheels |
| With direct mount top flange according to ISO 5211 | No |
| Return at zero supply voltage | Yes |
| Deactivated when closed | Yes |
| Automatic stroke recognition | No |
| Adjustable position feedback signal | No |
| Auxiliary contacts | No |
| Auxiliary contacts optional | Yes |
| End contacts | None |
| Adjustable operating range | No |
| With mechanical setting indicator | Yes |
| Suitable for manual operation | Yes |
| Operating time | 150 s |
| Torque | 10 Nm |
| Potential free switch contact | No |
| Self-adjusting travel length | No |
| Max. angle of rotation | 95 ° |
| With safety function | Yes |
| Degree of protection (NEMA) | 2 |
| Degree of protection (IP) | IP54 |
| Max. electric power input | 5.5 A |
| Ambient temperature (min) | -30 °C |
| Ambient temperature (max) | 50 °C |
| Height | 85 mm |
| Width | 130 mm |
| Depth | 290 mm |
| Explosion-proof | No |
| Housing material | Plastic |
| Suitable for valve | No |
Item number: 23010054
Item number: 23010063
