Helios Fans VDD 355/4 Ex

The Helios VDD 355/4 Ex is a centrifugal roof fan designed for vertical air discharge in hazardous locations, certified to meet ATEX explosion-proof standards. The casing is constructed from seawater-resistant aluminium and includes integrated anti-intrusion protection to enhance operational safety.

The motor support plate and base plate are made of galvanized steel, complemented by an aluminium inlet nozzle for corrosion resistance. The base plate includes a threaded screw on the intake side for secure attachment of accessories, following the DIN 24155 hole pattern (sheet 3). A protective grille is provided on the discharge side as standard, compliant with DIN EN ISO 13857 safety regulations.

This model features a high-efficiency backward-curved centrifugal impeller crafted from aluminium, dynamically balanced according to DIN ISO 1940 – 1 for smooth and vibration-free operation.

Power is delivered by a totally enclosed, speed-controllable three-phase external rotor motor rated IP 44. The motor is mounted on ball bearings with moisture protection, designed for maintenance-free and interference-free performance. The explosion-proof construction ensures safe operation in ATEX-regulated hazardous environments.