DOSATORE DI SICUREZZA PER ACQUE POTABILI, CON IDROMODULATORE E MEZZI DI BLOCCO DEL DOSAGGIO, PER LA DOSATURA DI POLIFOSFATI IN POLVERE

The present invention concerns a safety metering device for potable water with hydromodulator and means for blocking metering for determination of powder polyphosphates characterized by the fact that it comprises a hydromodulator consisting of a zone of reduced cross section inserted in the line and equipped with an elastic flap moved by the flowing water in the line and capable of increasing the diameter of the passage on an increase in flow rate. Upstream of the flap a bypass line is developed for input to a metering group containing powdered polyphosphates. A diaphragm is also provided on which the pressure in the bypass input line acts and which controls a blocking cylinder loaded by a spring and controlling a calibrated hole for connection to the bypass output line that discharges downstream of the flap.