Belimo SM230A rotary damper actuator, 20 Nm, 230 V, 150 s, IP54
- Application: air damper control in HVAC and VAV systems
- Torque: 20 Nm
- Power + control: 230 V AC, on/off or 3-point
- Running time + IP: 150 s / 95°, IP54
Where SM230A is used
SM230A is a standard-class Belimo actuator for medium-size air dampers: supply and exhaust sections, economiser mixing/return/outdoor dampers, zonal air distribution in high-flow ducts. Chosen when on/off or 3-point control is sufficient (no proportional position needed) and 230 V is already available at the damper section.
Compared to the Belimo LM (5 Nm), the higher torque covers dampers up to ~4 m² (LM tops out at ~1 m²). The universal shaft adapter fits 10 ... 20 mm round or square shafts, so it works with most damper brands (Trox, Systemair, Halton, etc.).
Technical specifications
| Parameter | Value |
|---|---|
| Code | SM230A |
| Manufacturer / series | Belimo, S series (standard, non-spring-return) |
| Torque | 20 Nm |
| Nominal voltage | AC 230 V, 50/60 Hz |
| Voltage range | AC 198 ... 264 V |
| Control signal | On/off or 3-point (open/close, open/close/stop) |
| Running time | 150 s / 95° |
| Rotation angle | Max. 95° (adjustable mechanical stops) |
| Shaft clamp | 10 ... 20 mm (round or square) |
| Damper area (recommended) | Up to ~4 m² |
| Auxiliary switch | 1 × SPDT (1 mA ... 3 A, AC 250 V, 0-100 % adjustable) |
| Position indicator | Mechanical, visible on housing |
| Protection class | IP54 (any mounting position) |
| Ambient temperature | -30 ... +50 °C |
| Connection | Cable 1 m, 3 × 0.75 mm² |
| Sound power level | Max. 45 dB (A) |
| Maintenance | Not required (lubrication-free) |
When to choose SM230A
- Ventilation dampers up to ~4 m² with 230 V available at the section
- Economiser section in AHU systems (outdoor/return/mixing) with BMS 3-point control
- Smoke exhaust (non-fire-rated) and aeration dampers where fail-safe is not required
- Where the standard 20 Nm class covers the damper with reserve (+25 % over theoretical — common practice)
- Compatibility: fits any damper brand with 10-20 mm shafts; direct shaft mounting with a single adapter (no lever mechanism)
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 for actuator sizing to your damper
Official Belimo catalogue: belimo.com/damper-actuators
Frequently asked questions
Can SM230A accept a 0-10 V signal?
No. SM230A supports only on/off (two-position) or 3-point (open/close/stop) control. For proportional 0-10 V positioning use Belimo SM24A-SR or SM230A-SR (SR suffix = stetless, modulating).
What damper area can a 20 Nm actuator realistically drive?
Belimo rates ~4 m² for new dampers with good seals. In practice, apply a 25-30 % reserve for older damper resistance, so the effective design limit is ~3 m². For heavier dampers use two SM24A-SR units or the GM series (40 Nm).
What does the "A" stand for — SM230A vs SM230?
"A" indicates an integrated 1 × SPDT auxiliary switch (0-100 % adjustable). Used for end-position confirmation to a BMS (e.g. "damper 100 % open" → start fan). SM230 (without "A") has no switch.
Can rotation direction be reversed?
Yes — reversible. Direction is switched by a selector on the housing (clockwise or counter-clockwise), so one actuator suits both left- and right-hand mounting positions.
What are the IP54 limits?
IP54 = protection against dust (dust protected, not dust tight) and water splash from any direction. Not suited for outdoor installation without an enclosure — for permanent outdoor use, a Belimo weather shield or the spring-return N4H series (NEMA 4) is required.
