The company introduced a family of compact, radial fans with free-running impellers and variable speeds that combine electronically commutated external-rotor motors with newly developed integrated power electronics. Designated as Models GKHR and GKHM, the new fans’ long-life, low-temperature brushless dc motors are controlled by maintenance-free electronic circuitry. GKHR fans are motorized impellers, mounted and balanced, that may be provided with or without an inlet cone. GKHM fans are complete fan modules.
The fans’ external rotor design and high power density make them ideal for use in ventilation and air-conditioning applications. With reduced mechanical content, the fan motors run cooler and quieter, require little or no maintenance, and can be speed-controlled using an external potentiometer or 0–10 V PWM signal. Unlike conventional dc motors, the new EC motors deliver highly efficient, low-noise performance without using collectors or carbon brushes that wear out and shorten motor life. Also in the new models, both the power supply and control leads connect directly at the motor, simplifying installation.