Description
The Belimo EFB24-MFT-S is a high-torque spring return damper actuator delivering 270 in-lb (30 Nm) for precise and configurable airflow control in HVAC systems. It operates on AC/DC 24 V power and combines MFT programmable control with integrated auxiliary switches for enhanced monitoring and safety functions.
Technical Specifications
| Condition |
New/Never Used Surplus |
| Brand |
Belimo |
| Category |
Actuators & Dampers |
| Part Number |
EFB24-MFT-S |
| Subcategory |
Damper Actuators |
| Nominal Voltage |
AC/DC 24 V |
| Nominal Frequency |
50/60 Hz |
| Voltage Range |
AC 19.2…28.8 V / DC 21.6…28.8 V |
| Power Consumption (Operation) |
9.5 W |
| Power Consumption (Rest) |
4.5 W |
| Transformer Sizing |
16 VA |
| Control Signal |
MFT programmable, 2…10 V |
| Input Impedance |
100 kΩ (2…10 V), 500 Ω (4…20 mA), 1500 Ω (PWM/On-Off/Floating) |
| Operating Modes |
VDC, PWM, On/Off, Floating Point |
| Position Feedback |
2…10 V |
| Torque Output |
270 in-lb (30 Nm) |
| Angle of Rotation |
35…95°, adjustable |
| Running Time (Motor) |
60…150 s / 90° |
| Running Time (Fail-Safe) |
<20 s @ -20…50°C |
| Auxiliary Switches |
2x SPDT |
| Electrical Connection |
Dual 18 GA cables, 1 m, 1/2" conduit |
| Ambient Temperature |
-30…50°C |
| Weight |
12 lb (5.3 kg) |
Information About EFB24-MFT-S
The EFB24-MFT-S is part of Belimo’s EFB series of heavy-duty spring return actuators designed for demanding HVAC damper applications. It integrates Belimo MFT multi-functional technology, allowing field configuration of control signals, operating ranges, and actuator behavior to match specific system requirements. The actuator includes two factory-installed auxiliary switches to support position indication, interlocking, and safety-related control logic. Electronic overload protection, double insulation, and adjustable mechanical end stops ensure consistent performance, installation flexibility, and long-term reliability.
Key Features
- Spring Return Fail-Safe Operation: Integrated spring mechanism ensures rapid return to a defined safety position during power loss to protect HVAC systems and equipment.
- High Torque Performance: Provides a constant 270 in-lb (30 Nm) torque output suitable for large or high-pressure air damper applications.
- MFT Programmable Control Technology: Supports configurable control modes including 2…10 V, 4…20 mA, PWM, on/off, and floating point for broad system compatibility.
- Dual Auxiliary SPDT Switches: Includes two adjustable auxiliary switches for precise position indication, sequencing, and safety interlocks.
- Configurable Control Range: Adjustable start and end points allow accurate alignment of actuator response with building automation requirements.
- Electronic Overload Protection: Protects internal components throughout the full 0…95° rotation range against mechanical overload or obstruction.
- Manual Override Capability: Supplied hex crank enables manual damper positioning during commissioning, testing, or maintenance.
The EFB24-MFT-S delivers the reliability and precision required for programmable airflow modulation and dependable fail-safe damper operation in HVAC systems.
