The Belimo UMB24Y-SR-F-R is a compact non-spring-return rotary damper actuator delivering 9 in-lb [1 Nm] of torque with modulating 2-10 VDC control on AC/DC 24 V power. As one of Belimo's smallest rotary actuators, it drives small dampers through clockwise (CW) 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-SR-F-R technical data sheet (rev 2026-03-18).
Overview
Belimo UM-Series actuators are Belimo's smallest non-spring-return rotary drives, for small commercial HVAC dampers and zone control. The UMB24Y-SR-F-R produces 9 in-lb [1 Nm] and rotates clockwise (CW) (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-SR connecting cable. A 2-10 VDC signal modulates the damper with 2-10 VDC position feedback.
Best for
- Modulating small-damper control (2-10 VDC, 9 in-lb)
- Non-spring-return applications (no fail-safe required)
- Tight spaces needing a very compact rotary actuator
- Square (8x8 mm) damper shafts
- Clockwise (cw) 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.
Modulating 2-10 VDC
Accepts a 2-10 VDC control signal with 2-10 VDC position feedback for proportional damper control.
CW Rotation
Factory-set clockwise (CW) rotation. Choose the -L (CCW) 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-SR cable (socket not included).
Technical Specifications
| Parameter | Specification |
|---|---|
| Manufacturer | Belimo |
| Part Number | UMB24Y-SR-F-R |
| 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 | Modulating |
| Operating Range (Y) | 2-10 VDC (also 0.5-10 V / variable) |
| Position Feedback (U) | 2-10 VDC (max. 0.5 mA) |
| Mechanical Interface | Form-fit 8x8 mm square coupling |
| Angle of Rotation | 95° (adjustable end stops) |
| Direction of Rotation | clockwise (CW) — 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-SR 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-SR-F-R 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-SR-F-R?
The Belimo UMB24Y-SR-F-R 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 modulating 2-10 VDC control on AC/DC 24 V power, rotates clockwise (CW), and holds its last position on power loss.
Does the UMB24Y-SR-F-R need a separate cable?
Yes. The UMB24Y-SR-F-R terminates in a locking Molex plug and the cable-side socket is not included. Order the Z-C24UM-SR 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-SR-F-R is a CW model; choose the opposite-suffix part for the other direction.
What does the -F mean on the UMB24Y-SR-F-R?
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-SR-F-R spring-return?
No. The UMB24Y-SR-F-R 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-SR-F-R available from an authorized Belimo distributor?
Yes. ZOT Supply is an authorized Belimo distributor and carries the UMB24Y-SR-F-R. 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:
- Modulating
- Voltage:
- 24 VAC/DC
- Series:
- UM
- Rotation:
- CW (Right)
- Shaft Coupling:
- Form-Fit 8x8 mm
