The Belimo AFB24-IP is a spring-return (fail-safe) damper actuator delivering 180 in-lb [20 Nm] of torque with communicating BACnet/IP, Modbus TCP and Belimo Cloud on 24 VAC/DC power. It direct-couples to damper shafts up to 1.05 in. diameter and drives to a mechanical fail-safe position on power loss, making it a proven member of the AFB spring-return platform for commercial HVAC damper control.
Specifications sourced from the official Belimo AFB24-IP technical data sheet.
Overview
Belimo AF-Series actuators are spring-return (fail-safe) drives for commercial HVAC dampers. The AFB24-IP produces 180 in-lb [20 Nm] of torque, mounts directly to the damper shaft, and On loss of power the spring drives the damper to its defined fail-safe position within the rated fail-safe time. It is controlled over BACnet/IP, Modbus TCP or the Belimo Cloud through an RJ45 connection, with an integrated web server for setup, plus a 2-10 VDC hybrid local-control option.
Best for
- IP / BACnet networked damper control
- Belimo Cloud monitoring and diagnostics
- Smart-building and analytics integration
Key Features
True Spring Return Fail-Safe
Constant-torque spring drives the damper to a defined safe position on power loss — no mechanical end switches required, and positive close-off on air-tight dampers.
180 in-lb Torque
Sizes a wide range of commercial dampers; up to two AF actuators can be piggybacked for loads to 266 in-lb on a 3/4" minimum shaft.
Native IP Communication
BACnet/IP, Modbus TCP and Belimo Cloud over an RJ45 connection, with an integrated web server for setup and diagnostics.
Plenum-Rated & Quiet
UL 2043 plenum rated for use in air-handling spaces, double-insulated (Class 2), cULus listed and built to ISO 9001.
Technical Specifications
| Parameter | Specification |
|---|---|
| Manufacturer | Belimo |
| Part Number | AFB24-IP |
| Actuator Type | Spring-Return (Fail-Safe) Damper Actuator |
| Nominal Voltage | AC/DC 24 V |
| Nominal Voltage Range | AC 19.2-28.8 V / DC 21.6-28.8 V |
| Nominal Frequency | 50/60 Hz |
| Transformer Sizing | 8.5 VA |
| Torque | 180 in-lb [20 Nm] |
| Control Type | Communicating - BACnet/IP, Modbus TCP, Belimo Cloud |
| Communication Port | RJ45 socket (Ethernet) |
| Local Hybrid Control | 2-10 VDC position signal (S1) |
| Angle of Rotation | 95° (adjustable end stop 35-95°) |
| Running Time (Motor) | 150 s (default), 70-220 s variable |
| Running Time (Fail-Safe) | <20 s @ -4 to 122°F [-20 to 50°C]; <60 s @ -22°F [-30°C] |
| Manual Override | 5 mm hex crank (3/16" Allen), supplied |
| Direction of Motion | Selectable CW/CCW |
| Position Indication | Mechanical |
| Electrical Connection | 18 AWG appliance cable, 3 ft [1 m], 1/2" NPT conduit connector |
| Overload Protection | Electronic, full 0-95° rotation |
| Electrical Protection | Double insulated (Class 2) |
| Enclosure Rating | NEMA 1 / UL Type 1 |
| Housing Material | Zinc-coated metal and plastic |
| Ambient Temperature | -22 to 122°F [-30 to 50°C] |
| Storage Temperature | -40 to 176°F [-40 to 80°C] |
| Agency Listing | cULus (UL60730-1A / -2-14, CAN/CSA) |
| Quality Standard | ISO 9001 |
| Weight | 4.6 lbs [2.1 kg] |
| Warranty | 5 Years |
Documentation
Related Products
Accessories & Mounting
Common Belimo accessories for mounting, linkage, signaling and powering the AFB24-IP, drawn from the actuator datasheet. All are stocked by ZOT Supply as an authorized Belimo distributor.
Mounting & Linkage
Electrical Add-Ons
Frequently Asked Questions
What is the Belimo AFB24-IP?
The Belimo AFB24-IP is a spring-return (fail-safe) damper actuator for commercial HVAC. It produces 180 in-lb [20 Nm] of torque, uses communicating control over BACnet/IP, Modbus TCP and the Belimo Cloud on 24 VAC/DC power, and drives the damper to a mechanical fail-safe position on loss of power. Its housing is rated NEMA 1 / UL Type 1.
How does the AFB24-IP fail safe on power loss?
The AFB24-IP stores energy in a return spring during normal operation. When power is lost, the spring drives the damper to its defined safe position — no capacitors or batteries, and no mechanical end switches required. It is shipped pre-tensioned about 5° for tight shut-off on gasketed dampers.
What torque does the AFB24-IP provide and what shaft sizes does it fit?
It delivers 180 in-lb [20 Nm] and direct-couples to round or square damper shafts up to 1.05 in. diameter using its universal clamp. Up to two AF actuators can be piggybacked for loads to 266 in-lb on a 3/4 in. minimum shaft.
What control signal does the AFB24-IP use?
It uses communicating control over BACnet/IP, Modbus TCP and the Belimo Cloud. It connects via an RJ45 port with an integrated web server, plus a 2-10 VDC hybrid local-control option.
What is the running time of the AFB24-IP?
Motor running time is about 150 seconds for 90° of travel, and the spring-return fail-safe time is under 15 seconds at normal temperatures (under 60 seconds at -22°F [-30°C]).
Is the AFB24-IP UL listed for damper control?
Yes. The AFB24-IP is cULus listed to UL60730 and CAN/CSA, is double-insulated (Class 2), and carries the listings shown on its datasheet.
Is the Belimo AFB24-IP available from an authorized Belimo distributor?
Yes. ZOT Supply is an authorized Belimo distributor and carries the AFB24-IP. Every unit ships factory-new with Belimo's full 5-year warranty and application support from our team.
- Actuator Type:
- Fail-Safe
- Torque:
- 180 in-lb
- Control Signal:
- BACnet/IP
- Voltage:
- 24 VAC/DC
- Auxiliary Switch:
- No
- Enclosure:
- NEMA 2
- Series:
- AF
