Abstract: A fiber collector collects fiber from a moving airflow having entrained fibers. A primary plenum has a fiber collection zone in its lower portion. Adjacent screens downstream of the primary plenum are slanted with respect to the primary plenum so that fiber held by the screens will be gravitationally attracted to the fiber collection zone. Secondary plenums downstream of the screens have independently openable air inlets and independently closable passages. A fan downstream of the passages pulls air through the primary plenum, screens, secondary plenums and passages. Pressure sensors upstream of the screens and downstream of the passages provide pressure sense data to a control means which closes the passages for one of the secondary plenums and opens the independently openable air inlet of the same secondary plenum when the pressure difference between the first and second pressure sensors exceeds a desired range.