Belimo LF230 spring-return fail-safe damper actuator, 4 Nm, 230 V
- Application: fire-safety, smoke exhaust, filtered-air protection dampers
- Torque: 4 Nm (nominal and spring return)
- Power + control: 230 V AC, on/off (open/close)
- Running time + IP: ~75 s motor + 20 s spring return, IP54
Where LF230 is used
LF230 is a fail-safe actuator: an integrated mechanical spring returns the damper to a preset safe position (typically CLOSED) when 230 V power is removed. This principle is critical for fire-safety and hygiene protection applications:
- Air distribution dampers used to shut off supply on fire alarm
- HEPA filtered-air protection dampers — closed on power loss
- Smoke exhaust dampers — spring guarantees opening even on controller fault
- Cleanroom atmosphere isolation — spring isolates the room on system fault
Compared to the standard LM230A (5 Nm, no spring), LF230 adds mechanical return — a more expensive but single-fault-tolerant solution. So the LF230 selection criterion is not airflow but the requirement for a safe fallback position.
Technical specifications
| Parameter | Value |
|---|---|
| Code | LF230 |
| Manufacturer / series | Belimo, LF series (spring return) |
| Nominal torque | 4 Nm (motor) |
| Spring return torque | 4 Nm (spring) |
| Nominal voltage | AC 230 V, 50/60 Hz |
| Voltage range | AC 198 ... 264 V |
| Power consumption | 5 W (running) / 3 W (holding) |
| Control signal | On/off (open/close, no intermediate positions) |
| Running time (motor) | ~75 s / 90° |
| Spring return time | ~20 s / 90° |
| Rotation angle | Max. 95° (37-100 % adjustable stops) |
| Damper area (recommended) | Up to ~0.8 m² |
| Shaft clamp | Round or square 10-20 mm |
| Position indicator | Mechanical (0-95° scale) |
| Protection class | IP54 |
| Ambient temperature | -30 ... +50 °C |
| Connection | Cable 1 m, 3 × 0.75 mm² |
| Expected service life | Min. 60,000 cycles / 10 years (Belimo warranty — 5 y) |
When to choose LF230
- Hygiene zone filter-protection dampers (food, pharma, cleanroom)
- General ventilation protection dampers that must shut off airflow on power loss
- Smoke exhaust dampers requiring spring-open behaviour (non-EI-certified)
- Where the mains supply is reliable but a controller fault must not compromise safety
- Compatibility: universal shaft clamp for 10-20 mm round / square damper shafts; for certified fire dampers (Trox FKR/FKA, Systemair FID) check the manufacturer's approved actuator list
B2B delivery and logistics via Amegata.lt
- 24-hour delivery across Lithuania (from our warehouse in Vilnius)
- Competitive B2B pricing — often below market average
- 30-day payment terms for companies (per contract)
- Free technical consultation on fire-safety actuator selection per STR
Official Belimo catalogue: belimo.com/damper-actuators-fail-safe
Frequently asked questions
What does "spring-return fail-safe" mean?
Fail-safe — on 230 V power loss, the built-in mechanical spring returns the damper to a preset safe position (typically CLOSED). Protection against electrical or controller faults: the damper still closes even with the whole BMS system down. Return takes ~20 seconds.
Is LF230 suitable for certified fire-rated dampers (EI-60, EI-120)?
Not directly. Fire dampers with EI certification require the Belimo BF-T series with thermal fuse (72 °C release) AND an approved combination with the specific damper (Trox, Systemair, Halton). LF230 suits non-fire-rated safety dampers. Verify the manufacturer's certificate before ordering.
What is the fail-safe position — open or closed?
LF230 returns to the CLOSED (0°) position by default. The direction is set by wiring and mounting orientation. The LF230-S variant adds a SPDT switch for end-position confirmation.
How many times can the spring operate?
Belimo guarantees min. 60,000 cycles (motor + spring); in field practice systems run 10+ years without failure inside IP54 limits (no continuous moisture). No periodic spring-activation tests are required by design.
Can it be used on 24 V?
No — LF230 is 230 V only. The 24 V version is Belimo LF24 (or LF24-S with an AUX switch). Mechanical data (4 Nm, ~0.8 m², IP54, return time) is identical.
