The medium to be filtered enters the filter through inlet nozzle (below the division plate), flows through the holes of the division plate into the
filter elements from below and runs through them from inside to outside, before the medium leaves the filter through the outlet nozzle. Thereby, all dirt particles, whose "diameter" is larger than
that of the slot, are retained at the inner side of the filter elements.
The free filter area of the filter elements is reduced with increasing contamination which causes a higher pressure drop.
If the manually adjusted differential pressure (max. 1 bar) between contaminated and clean side is reached, an electric circuit is closed via the differential pressure contact gauge. The control uses that
signal to release self-cleaning by backwashing.
The shut-off valve at the backwash nozzle is opened and the gear motor for rotation of the backwash arm is initiated.
Because of the pressure drop between
clean side of the filter and backwash connection a part of the filtered medium runs through the filter cartridge, above which the backwash arm is located at the time, from inside to outside and washes the
dirt particles sticking at the inner side of the filter cartridges out of the filter through the outlet nozzle.
The control terminates the self-cleaning process after one rotation of the
backwash arm by closing the shut-off valve at the backwash nozzle and switching off the gear motor. Thus, the filter elements are cleaned.
