A freestanding mains electricity (AC-powered) device used mainly in a blood donor facility to process through centrifugal force (typically up to 10,000 rpm) a large volume of blood, usually to separate red blood cells or platelets from plasma for subsequent patient infusion, storage, or further processing. It is typically a large stationary structure with an electric motor, a shaft, a tachometer, and speed and time controls; it also includes a rotor for mounting one of several interchangeable heads with slots to fit sample holders (tubes/bags). Some types are available with refrigeration of the rotor chamber.