A method for processing pharmaceutical powders, which comprises providing a feeder module including a plurality of feeder units each with a storage hopper, a weighing cell, a conveyer, and a discharge end, connecting the storage hopper to a refilling system with a refilling valve, connecting the refilling valve to a level or weight indicator disposed above the refilling valve, connecting the discharge end to a common receiving container, refilling the storage hopper with a powder intermittently 40 to 80 times per hour, storing data during refilling, transporting powder from the storage hopper with the respective conveyer, and discharging powder from each feeder unit into the common receiving container. During each refilling of the storage hopper, the refilling valve dispenses powder into the storage hopper and, during the step of transporting the powder from the storage hopper, the conveyer is operated according to the data collected during previous refills.