A new automatic backwashing method for water filters with multiparallel connection and high flux was proposed.First

four variables

i.e.concentrated water flux

shunt water flux

pollution index of source water and the number of multiparallel filters

for automatic back wash were assumed and through the controller above mentioned data were obtained by on-line inspection.The through the treatment of software mathematic model the jamming condition of the filters was detected and a backwashing signal was given to open the back washing value and carry out back wash. Finally

back wash was ended and the controller automatically switched to run.The proposed detection method is simple and reliable

do not require manometer

switches precisely and decreases the switch number of back washing

assures the stability of intermediate product water quality

the life time of equipments and saves energy and water.The controller was consisted of a single chip Micyoco and a software mathematic model was built.