The Belimo LM24A-MOD is a compact non-spring-return damper actuator delivering 45 in-lb [5 Nm] of torque with multi-protocol control over BACnet MS/TP, Modbus RTU and Belimo MP-Bus (plus analog 2-10 V, variable 0.5-10 V) on AC/DC 24 V power. It couples via a universal shaft clamp, 6-20 mm [approx. 1/4 in. to 3/4 in.] and is non-fail-safe, with no spring return, making it Belimo's multi-protocol LM24A actuator for small to mid-size commercial HVAC dampers.
Specifications sourced from the official Belimo LM24A-MOD technical data sheet (rev 2025-10-06).
Overview
Belimo LM-Series actuators are compact non-spring-return drives for small and mid-size commercial HVAC dampers — they position the damper under power and have no spring-return fail-safe function. The LM24A-MOD produces 45 in-lb [5 Nm] and mounts directly to universal shaft clamp, 6-20 mm [approx. 1/4 in. to 3/4 in.]. One part number speaks BACnet MS/TP, Modbus RTU and Belimo MP-Bus, and also accepts analog control over 2-10 V (variable 0.5-10 V) with 2-10 V feedback.
Best for
- Multi-protocol BACnet MS/TP, Modbus RTU or MP-Bus networks
- Mixed analog + networked retrofits
- Compact non-spring-return applications
Key Features
Non-Spring-Return Design
No fail-safe spring return. Belimo does not publish a defined position on loss of power for this model; specify a spring-return actuator where a fail-safe position is required.
45 in-lb Torque
Sized for small and mid-size dampers; couples via a universal shaft clamp, 6-20 mm [approx. 1/4 in. to 3/4 in.].
Multi-Protocol Communication
One actuator speaks BACnet MS/TP, Modbus RTU and Belimo MP-Bus, plus analog control over 2-10 V, variable 0.5-10 V.
cULus Listed & Quiet
cULus listed (UL60730-1A, UL60730-2-14) for long, maintenance-free service.
Technical Specifications
| Parameter | Specification |
|---|---|
| Manufacturer | Belimo |
| Part Number | LM24A-MOD |
| Actuator Type | Non-Spring-Return (Non Fail-Safe) Damper Actuator |
| Nominal Voltage | AC/DC 24 V |
| Nominal Frequency | 50/60 Hz |
| Power Consumption (Running) | 2.5 W |
| Transformer Sizing | 5 VA Connection supply/control cable 3 ft. [1 m], 6x 0.75 mm² |
| Torque | 45 in-lb [5 Nm] |
| Control Type | Communicating — BACnet MS/TP, Modbus RTU, Belimo MP-Bus, or conventional analog |
| Analog Control | Operating range Y 2-10 V; variable 0.5-10 V |
| Position Feedback | 2-10 VDC |
| Mechanical Interface | Universal shaft clamp, 6-20 mm [approx. 1/4 in. to 3/4 in.] |
| Angle of Rotation | Max. 95° (adjustable mechanical stop) |
| Running Time (Motor) | 150 s / 90° |
| Variable Running Time | 35-150 s |
| Behavior on Power Loss | Non fail-safe — no fail-safe spring return function |
| Manual Override | External push button |
| Direction of Motion | Selectable with 0/1 switch |
| Electrical Connection | Supply/control cable, 3 ft [1 m], 6x 0.75 mm² |
| Overload Protection | Electronic, full 0-95° rotation |
| Power Source | UL Class 2 Supply |
| Enclosure Rating | NEMA 2 / UL Type 2 / IP54 |
| Ambient Temperature | -22 to 122°F [-30 to 50°C] |
| Agency Listing | cULus according to UL60730-1A, UL60730-2-14 |
| Weight | 1.2 lb [0.55 kg] |
| Warranty | 5 Years |
Documentation
Accessories & Mounting
Common Belimo accessories for mounting, linkage, signaling and powering the LM24A-MOD, drawn from the actuator datasheet. All are stocked by ZOT Supply as an authorized Belimo distributor.
Mounting & Linkage
Electrical Add-Ons
Enclosures & Weather Shields
Frequently Asked Questions
What is the Belimo LM24A-MOD?
The Belimo LM24A-MOD is a compact non-spring-return (non-fail-safe) damper actuator for commercial HVAC. It produces 45 in-lb [5 Nm] of torque, uses multi-protocol control (BACnet MS/TP, Modbus RTU, MP-Bus, plus analog) on AC/DC 24 V power. It is non-fail-safe: Belimo does not publish a defined position on loss of power for this model. Its housing is rated NEMA 2.
Is the LM24A-MOD a spring-return (fail-safe) actuator?
No. The LM24A-MOD is non-spring-return: it has no fail-safe spring, so it will not drive to a predetermined position when power is lost. Where a defined position on power loss is required, select a spring-return actuator sized to the damper manufacturer's specifications.
What happens to the LM24A-MOD when power is lost?
There is no spring return, so the actuator does not drive itself to a fail-safe position. Belimo's datasheet for this model does not publish a defined power-loss position; if your sequence depends on a specific position during a power failure, specify a spring-return actuator.
What shaft sizes does the LM24A-MOD fit?
It couples via a universal shaft clamp, 6-20 mm [approx. 1/4 in. to 3/4 in.] using its universal clamp.
What control signal does the LM24A-MOD use?
It uses multi-protocol control (BACnet MS/TP, Modbus RTU, MP-Bus, plus analog). One unit speaks BACnet MS/TP, Modbus RTU and MP-Bus, and also accepts analog control over 2-10 V, variable 0.5-10 V.
What is the running time of the LM24A-MOD?
Motor running time is 150 s / 90°.
Is the Belimo LM24A-MOD available from an authorized Belimo distributor?
Yes. ZOT Supply is an authorized Belimo distributor and carries the LM24A-MOD. Every unit ships factory new with Belimo's full 5-year warranty and application support.
- Actuator Type:
- Non-Fail-Safe
- Torque:
- 45 in-lb
- Control Signal:
- Multi-Protocol
- Voltage:
- 24 VAC/DC
- Auxiliary Switch:
- No
- Series:
- LM
- Feedback Signal:
- 2-10 VDC
