Helios Fans SKRD 500÷6÷70÷40

The Helios SKRD 500÷6÷70÷40 is a noise-reduced rectangular centrifugal fan designed for direct installation into rectangular duct systems. It features a compact casing made of galvanised steel with flanged ends, acoustically lined with 50 mm thick mineral fibreboard to reduce sound emissions. Maintenance is made simple by the swing-out motor and impeller unit, allowing easy access for cleaning and servicing.

The fan is equipped with a highly efficient centrifugal impeller with backward curved blades made from impact-resistant polymers and galvanised steel. This impeller is dynamically balanced to Class G 6.3 according to VDI 2060 and ISO 1940 standards, ensuring quiet and smooth operation.

Powered by a totally enclosed 3‑phase external rotor motor with thermal contacts wired to the terminal box, the fan offers flexible speed control options. These include a 5‑step transformer controller, an electronic stepless controller, or a Helios frequency inverter with sinus filter on all poles. The motor is maintenance-free, fitted with low-noise sealed-for-life ball bearings and tropical winding protection. The power supply is delivered through a pre-assembled IP55-rated terminal box.