Helios Fans VDD 250/4 Ex

The Helios VDD 250/4 Ex is a centrifugal roof fan designed for vertical air discharge in hazardous environments, fully compliant with ATEX explosion-proof standards. The fan casing is made of seawater-resistant aluminium, incorporating integrated anti-intrusion protection for enhanced safety and durability.

The motor support plate and base plate are constructed from galvanized steel, while the inlet nozzle is crafted from aluminium to resist corrosion. The base plate includes a threaded screw on the intake side for secure accessory attachment, with flange hole patterns matching DIN 24155, sheet 3 specifications. A protective grille is installed on the discharge side as standard, meeting DIN EN ISO 13857 safety requirements.

Equipped with a high-efficiency backward-curved centrifugal impeller made of aluminium, the fan ensures optimal airflow and is dynamically balanced to DIN ISO 1940 – 1 standards for vibration-free operation.

Power is provided by a totally enclosed, speed-controllable three-phase external rotor motor with an IP 44 rating. The motor is mounted on ball bearings with moisture protection, designed to be maintenance-free and interference-free. This explosion-proof fan is ideal for industrial ventilation in hazardous areas requiring ATEX certification.