Helios Fans KRD 560÷4÷80÷50

The Helios KRD 560÷4÷80÷50 is a rectangular centrifugal fan designed for direct installation into rectangular duct systems. It features a galvanized steel casing with flanged ends and a compact design that facilitates maintenance through a swing-out motor and impeller unit. From size 450 upwards, the swing-out assembly includes an additional locking mechanism for enhanced safety.

The fan uses a backward curved centrifugal impeller made of polymer, dynamically balanced according to DIN ISO 1940 Pt.1, ensuring quiet operation. It is powered by a totally enclosed three-phase external rotor motor with integrated thermal contacts wired to the terminal block. Speed regulation can be performed via a 5‑step transformer controller, a stepless electronic controller, or with a Helios frequency inverter fitted with an all-pole sinus filter. Maintenance-free, low-noise sealed-for-life ball bearings and tropical protection for the windings provide durability. The unit connects to the mains through a pre-assembled IP55-rated terminal box.