The Belimo LMQX24-1 is a compact non-spring-return damper actuator delivering 35 in-lb [4 Nm] of torque with on/off (two-position) control on AC/DC 24 V power. It couples to shafts from 1/2 in. to 1.05 in. via its standard universal clamp and is non-fail-safe, with no spring return, making it part of Belimo's configurable LMX platform for small to mid-size commercial HVAC dampers. A Q quick-running motor drives 90° in just 2.5 seconds.
Specifications sourced from the official Belimo LMQX24-1 technical data sheet (rev 2023-08-11).
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 LMQX24-1 produces 35 in-lb [4 Nm] and mounts directly to 1/2 in. to 1.05 in. via standard universal clamp. Its quick-running motor completes 90° in about 2.5 seconds. Two-position on/off control positions the damper from a controller, relay or switch.
Best for
- Compact non-spring-return damper control where fail-safe return is not required
- Small to mid-size damper and louver positioning (35 in-lb)
- Direct shaft mount, 1/2-1.05 in. via standard universal clamp
- Fast / high-cycle response (2.5-second run time)
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.
35 in-lb Torque
Sized for small and mid-size dampers; couples to shafts from 1/2 in. to 1.05 in. via its standard universal clamp.
Two-Position On/Off Control
Accepts two-position on/off control from a controller, relay or switch.
Quick 2.5-Second Run Time
A Q quick-running motor drives 90° in about 2.5 seconds for fast, high-cycle response.
cULus Listed & Quiet
cULus listed, ISO 9001 built, UL 2043 plenum-rated for long, maintenance-free service.
Technical Specifications
| Parameter | Specification |
|---|---|
| Manufacturer | Belimo |
| Part Number | LMQX24-1 |
| Actuator Type | Non-Spring-Return (Non Fail-Safe) Damper Actuator |
| Nominal Voltage | AC/DC 24 V |
| Nominal Frequency | 50/60 Hz |
| Power Consumption (Running) | 13 W |
| Transformer Sizing | 23 VA |
| Torque | 35 in-lb [4 Nm] |
| Control Signal | On/Off (two-position) |
| Mechanical Interface | 1/2 in. to 1.05 in. via standard universal clamp |
| Angle of Rotation | Max. 95° (adjustable mechanical stop) |
| Running Time (Motor) | 2.5 s / 90° |
| Running Time Note | constant, independent of load |
| Variable Running Time | 5 or 10 s |
| Sound Power Level (Motor) | 52 dB(A) |
| 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 | 18 AWG plenum cable, 3 ft [1 m], 1/2 in. NPT conduit connector |
| 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 (UL60730-1A / -2-14, CAN/CSA) |
| Quality Standard | ISO 9001 |
| Plenum Rated | UL 2043 (suitable for air plenums) |
| Weight | 1.9 lb [0.86 kg] |
| Warranty | 5 Years |
Documentation
Related Products
Accessories & Mounting
Common Belimo accessories for mounting, linkage, signaling and powering the LMQX24-1, 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 LMQX24-1?
The Belimo LMQX24-1 is a compact non-spring-return (non-fail-safe) damper actuator for commercial HVAC. It produces 35 in-lb [4 Nm] of torque, uses on/off (two-position) control 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 Enclosure UL Enclosure Type 2.
Is the LMQX24-1 a spring-return (fail-safe) actuator?
No. The LMQX24-1 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 LMQX24-1 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 LMQX24-1 fit?
It couples to shafts from 1/2 in. to 1.05 in. via its standard universal clamp using its universal clamp.
What control signal does the LMQX24-1 use?
It uses two-position on/off control, driven from a controller, relay or switch.
What is the running time of the LMQX24-1?
Motor running time is 2.5 s / 90°. The 'Q' quick-running design suits fast or high-cycle damper applications.
What is the difference between the Belimo LMQX24-1 and the LMQB24-1?
Both are non-spring-return actuators of the same torque class. Their published specifications are not identical: LMQX24-1 and LMQB24-1 differ on weight 1.9 lb vs 0.98 lb. LMQX24-1 additionally publishes a variable running time of 5 or 10 s; LMQB24-1 does not publish this field. Both datasheets state NEMA 2 / IP54 protection and the same electrical connection. Verify the exact control, running time, electrical, enclosure and mounting requirements before substituting one for the other.
Is the Belimo LMQX24-1 available from an authorized Belimo distributor?
Yes. ZOT Supply is an authorized Belimo distributor and carries the LMQX24-1. Every unit ships factory new with Belimo's full 5-year warranty and application support.
- Actuator Type:
- Non-Fail-Safe
- Torque:
- 35 in-lb
- Control Signal:
- On/Off
- Voltage:
- 24 VAC/DC
- Auxiliary Switch:
- No
- Series:
- LM
