Helios Ventilatoren VDD 250/4 EX roof fan
Manufacturer: Helios Ventilatoren
Designation: Roof fan 3-PH, 400 V, 4-pole
Type: VDD 250/4 EX
Nominal voltage: 400 V
Frequency: 50 Hz
Power consumption: 0.37 kW
Housing material: Aluminium
Air volume unloaded: 1280 m³/h
Medium temperature: -20 to 40 °C
Protection class (IP): IP44
Nominal duct diameter: 250 mm
For Ex zone gas: 2
Equipment group to Directive 94/9/EC: II
Explosion protection category for gas: ATEX Gas Ex protection, Cat. 3G
Temperature class to Directive 94/9/EC: T3

Helios Ventilatoren VDD 250/4 EX roof fan: further details
Vertical discharge roof fan with efficiency-optimised aluminium housing and newly developed high-performance radial impeller, explosion-proof to ATEX. Housing made of seawater-resistant aluminium with integrated anti-intrusion protection. Motor support plate and base plate made of galvanised steel with aluminium inlet nozzle. Base plate with threaded screw for mounting suction-side accessories (hole pattern according to DIN 24155, sheet 3). Guard grille as standard on the discharge side in accordance with DIN EN ISO 13857. High-performance radial impeller with backward curved blades made of aluminium. Dynamically balanced according to DIN ISO 1940-1. Speed-controllable three-phase external rotor motor in enclosed design to IP44. Ball bearings with moisture protection insulation. Maintenance-free and interference-free. Ex-version according to ATEX.