The unit consists of two stages of filtration, a coarse pre-filter (1) and a stainless steel fine screen (2).
Dirty water enters the inlet (3), passes through the coarse screen and into the center of the fine screen. The water then passes through the fine screen from the inside out and exits the outlet (4).
The unwanted solids accumulate on the inner surface of the fine screen, creating a pressure differential. Once the pressure drop reaches a preset level, a rinse cycle is activated by the factory supplied control system by opening the rinse valve (5) to an atmospheric drain. As a result, pressure drops in the hydraulic motor chamber (6) and dirt collector assembly (7). The pressure drop creates a backflush stream, which sucks the dirt off the screen, similar to a vacuum cleaner. The backwash water is carried through the collector and ejected out of the holes in the hydraulic motor (8).The water being ejected out of the hydraulic motor causes the collector to rotate, allowing the entire screen to be cleaned each cycle. Models with screen areas of 237 sq in or greater include a hydraulic piston (9), which is used to control the longitudinal movement of the collector. During the rinse cycle, the piston prevents the collector from traversing through its stroke too quickly, ensuring that the entire screen area is swept by the nozzles. Following the rinse cycle, the piston returns the collector to the top of its stroke in preparation for the next rinse cycle. 

The cleaning cycle takes a matter of seconds, and does not interrupt system flow.