Patent ID: 6429660
Filing Date: 2002-08-06
Classification: G01N

Abstract:
A process of operating a pH analyzer to measure pH of a solution, comprising steps of:a) providing a pH sensor having an ion-specific electrode and a reference electrode, the ion-specific electrode being in contact with the solution and designed to provide an electrical potential based on the pH of the solution, the reference electrode being designed to provide a reference electrical potential and being coupled to the ion-specific electrode through the solution; b) applying the pH sensor and a common electrode to the solution; c) measuring the pH of the solution during a first cycle of operation by c1) applying a first current, IGLASS, to the ion-specific electrode during a first time period, c2) applying a second current, IREF, to the reference electrode during a second time period that is mutually exclusive of the first time period, c3) measuring a voltage, VGLASS, between the ion-specific electrode and the common electrode, c4) measuring a voltage, VREF, between the reference electrode and the common electrode, c5) identifying the pH of the solution based on a difference between the measured voltages VGLASS and VREF.