The Belimo UMB24Y-F-L is a compact non-spring-return rotary damper actuator delivering 9 in-lb [1 Nm] of torque with on/off and floating-point control on AC/DC 24 V power. As one of Belimo's smallest rotary actuators, it drives small dampers through counter-clockwise (CCW) rotation and mounts with a form-fit 8x8 mm square coupling. It holds its last position on power loss (non-fail-safe) and connects through a locking Molex plug (IP20).
Specifications sourced from the official Belimo UMB24Y-F-L technical data sheet (rev 2026-03-19).
Overview
Belimo UM-Series actuators are Belimo's smallest non-spring-return rotary drives, for small commercial HVAC dampers and zone control. The UMB24Y-F-L produces 9 in-lb [1 Nm] and rotates counter-clockwise (CCW) (a separate model covers the opposite direction). It mounts in a form-fit manner on an 8x8 mm square shaft via its hollow shaft. It holds the last commanded position when power is removed (there is no spring-return fail-safe), and connects via a locking Molex plug — the cable-side socket is not included, so order the matching Z-C24UM connecting cable. Two-position on/off and 3-point floating control position the damper from a controller, relay or switch.
Best for
- Small commercial HVAC and zone dampers (9 in-lb)
- Non-spring-return applications (no fail-safe required)
- Tight spaces needing a very compact rotary actuator
- Square (8x8 mm) damper shafts
- Counter-clockwise (ccw) damper rotation
Key Features
Ultra-Compact 9 in-lb
One of Belimo's smallest rotary actuators — drives small dampers where space is tight, weighing under 6 oz.
Non-Spring-Return Design
Holds the last commanded position when power is removed (non-fail-safe), with a fast 22-second running time.
On/Off & Floating Point
Accepts two-position on/off or 3-point floating control from a controller, relay or switch.
CCW Rotation
Factory-set counter-clockwise (CCW) rotation. Choose the -R (CW) model for the opposite direction.
Form-Fit Square Coupling
A hollow-shaft form-fit 8x8 mm coupling drives square damper shafts directly — no clamp required.
Plug-In Molex Connection
A locking Molex plug speeds installation and allows parallel wiring. Order the Z-C24UM cable (socket not included).
Technical Specifications
| Parameter | Specification |
|---|---|
| Manufacturer | Belimo |
| Part Number | UMB24Y-F-L |
| Actuator Type | Non-Spring-Return (Non Fail-Safe) Rotary Damper Actuator |
| Nominal Voltage | AC/DC 24 V |
| Nominal Frequency | 50/60 Hz |
| Torque | 9 in-lb [1 Nm] (minimum) |
| Control Signal | On/Off and Floating Point (3-point) |
| Mechanical Interface | Form-fit 8x8 mm square coupling |
| Angle of Rotation | 95° (adjustable end stops) |
| Direction of Rotation | counter-clockwise (CCW) — factory-set by model (L=CCW, R=CW) |
| Running Time (Motor) | 22 s / 90° (constant) |
| Behavior on Power Loss | Holds last position (non-spring-return) |
| Manual Override | None (gear-disengagement magnet Z-MA available) |
| Electrical Connection | Molex connector plug (locking) — cable-side socket NOT included; order Z-C24UM cable |
| Electrical Protection | Double insulated (Class 2) |
| Enclosure Rating | IP20 / NEMA 1 (indoor) |
| Ambient Temperature | -22 to 122°F [-30 to 50°C] |
| Agency Listing | cULus (UL60730), CE |
| Quality Standard | ISO 9001 |
| Weight | 0.28 lb [0.13 kg] |
| Warranty | 5 Years |
Documentation
Related Products
Accessories & Cabling
The UMB24Y-F-L connects through a Molex plug, so the matching connecting cable is required (the cable-side socket is not included). All UM accessories below are stocked by ZOT Supply as an authorized Belimo distributor.
Frequently Asked Questions
What is the Belimo UMB24Y-F-L?
The Belimo UMB24Y-F-L is a compact non-spring-return (non-fail-safe) rotary damper actuator for small commercial HVAC dampers. It produces 9 in-lb [1 Nm] of torque, uses on/off and floating-point control on AC/DC 24 V power, rotates counter-clockwise (CCW), and holds its last position on power loss.
Does the UMB24Y-F-L need a separate cable?
Yes. The UMB24Y-F-L terminates in a locking Molex plug and the cable-side socket is not included. Order the Z-C24UM connecting cable (sold separately) to wire the actuator.
What do the -L and -R suffixes mean?
They set the factory direction of rotation: -L rotates counter-clockwise (CCW) and -R rotates clockwise (CW). The UMB24Y-F-L is a CCW model; choose the opposite-suffix part for the other direction.
What does the -F mean on the UMB24Y-F-L?
The -F denotes a form-fit 8x8 mm square coupling: the actuator's hollow shaft slips directly onto a square damper shaft, instead of clamping a round shaft.
Is the UMB24Y-F-L spring-return?
No. The UMB24Y-F-L is non-spring-return: on power loss it holds its last position rather than driving to a fail-safe position. It has no manual override, though the Z-MA gear-disengagement magnet allows manual positioning.
Is the Belimo UMB24Y-F-L available from an authorized Belimo distributor?
Yes. ZOT Supply is an authorized Belimo distributor and carries the UMB24Y-F-L. Every unit ships factory new with Belimo's full 5-year warranty and application support.
- Actuator Type:
- Non-Fail-Safe
- Torque:
- 9 in-lb
- Control Signal:
- On/Off / Floating
- Voltage:
- 24 VAC/DC
- Series:
- UM
- Rotation:
- CCW (Left)
- Shaft Coupling:
- Form-Fit 8x8 mm
