The Helios MBD 400÷4÷4 centrifugal fan is designed for quiet operation with acoustic insulation. Its casing is made from double-skinned galvanised steel lined internally with 30 mm mineral fibreboard to reduce noise effectively. Intake and exhaust spigots feature twin-seal rubber gaskets to ensure secure, airtight connections.
The motor and impeller unit can be swung out, providing easy access for cleaning and maintenance. This assembly is mounted on two strong rails and supported by four anti-vibration mounts to minimize noise and vibration during operation. The fan also includes a condensation drain and drip protection when the access door is opened, supplied as standard.
Equipped with a high-efficiency backward curved centrifugal impeller made from aluminium, the fan is dynamically balanced according to DIN 1940 and VDI 2060 standards, class G 6.3. It is powered by a totally enclosed, maintenance-free 3‑phase two-speed motor with star/delta connection and thermal protection. The motor operates quietly on low-noise, sealed-for-life ball bearings