Patent ID: 11940409
Assignee: ENDRESS+HAUSER CONDUCTA GMBH+CO. KG
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 6:
7. A measuring method of a digital pH sensor, comprising:
providing the digital pH sensor, comprising:
an electronics unit; and
a sensor housing having a first half-cell and a second half-cell,
wherein the first half-cell is a reference half-cell having: an electrolytic junction; a first electrolyte; and a first electrode in contact with the first electrolyte and electrically connected to the electronics unit,
wherein the second half-cell is a measuring half-cell having: a second electrolyte; and a second electrode in contact with the second electrolyte and electrically connected to the electronics unit,
wherein the first half-cell and the second half-cell are adapted to form a potential difference between the first electrode and the second electrode if the digital pH sensor is in contact with a measurement medium,
wherein the electronics unit is programmed with a correction function for converting the potential difference into a digital measured value, wherein the digital measured value is either a voltage value or a pH value,
wherein the first electrolyte and/or a material of the first electrode and/or the second electrolyte and/or a material of the second electrode are selected such that the potential difference between the first electrode and the second electrode, at a pH value of the measurement medium of 7 and a temperature of the measurement medium of 25° C., includes a preset potential difference that is greater than 30 mV or less than −30 mV, and
wherein the electronics unit programmed with the correction function is configured to convert the potential difference into the digital measured value and apply the correction function for correcting out the preset potential difference such that, at a pH value of the measurement medium of 7 and at a temperature of the measurement medium of 25° C. and the potential difference of greater than 30 mV or less than −30 mV, the digital measured value is 0 mV if the digital measured value is output as a voltage value or 7 if the digital measured value is output as a pH value;

measuring the potential difference between the first electrode and the second electrode using the electronics unit in the measurement medium, wherein the potential difference at a pH value of the measurement medium of 7 and at a temperature of the measurement medium of 25° C. includes the preset potential difference; and
converting the potential difference measured at a pH value of the measurement medium of 7 and at a temperature of the measurement medium of 25° C. into the digital measured value and applying the correction function for correcting out the preset potential difference using the electronics unit such that the digital measured value is 0 mV if the digital measured value is output as a voltage value or 7 if the digital measured value is output as a pH value.