Helios Fans KRD 500÷4÷80÷50 A

The Helios KRD 500÷4÷80÷50 A is a rectangular EC centrifugal fan designed for inline installation within rectangular duct systems. It features a galvanized steel casing with flanged ends, offering a compact and service-friendly design. The fan allows easy maintenance through a swing-out motor and impeller assembly.

The unit includes a high-performance radial impeller with backward curved blades made from plastic and galvanized steel. Dynamic balancing to quality level G 6.3 under DIN ISO 1940 T.1 ensures smooth, vibration-free operation. The fan is driven by a three-phase external rotor motor with integrated thermal contacts and an enclosed housing. Speed regulation is possible via a 5‑step transformer, continuous electronic control, or using a Helios frequency converter equipped with an all-pole sine filter. The motor windings are moisture-protected, and maintenance-free, low-noise ball bearings with long-life lubrication enhance reliability. The fan connects to mains power through a pre-installed IP54-rated terminal box.