A centrifugal separator, such as a spin dryer that separates water from wet clothing includes a stationary chamber. A perforated basket is arranged to spin within the stationary chamber. A DC or AC motor is arranged below the bottom floor fastened to a mechanical floor. A driveshaft can be connected to the motor output shaft via a flexible coupling and passes through the bottom floor and is connected to the basket. A brake disc is operatively fixed to the output shaft, and a brake caliper is fixed to the mechanical floor to stop the brake disc. A balance ring, having an annular chamber holding a balance fluid, is mounted to an outside of the basket. The centrifugal separator can include a cycle controller that can ramp up or down the basket speed and reverse spinning direction of the basket.