A method and apparatus extend the measurement life of a working electrode in a three-electrode amperometric sensor by applying an activation sequence of voltages and a measurement sequence of voltages to the input of a potentiostat. The activation sequence includes multiple cycles wherein each cycle includes a low (more negative) voltage and a high (more positive) voltage (e.g., 0 volts) with reference to a signal ground reference. In one mode, the measurement sequence includes multiple cycles of three voltage pulses, wherein each cycle includes a measurement voltage pulse followed by a high (more positive) pulse, followed by a low (more negative) pulse. The cycles are repeated N times. In a second mode, the measurement sequence comprises a fixed measurement voltage having selectable duration.
A sensor system that measures at least one parameter of water includes an electronics subsystem and includes a sensor housing electrically and mechanically coupled to the electronics subsystem. The sensor housing encloses a chamber that receives water via at least one inlet and that releases water via at least one outlet. At least one sensor has at least one electrode exposed to water in the chamber. A flow generator causes water to flow through the chamber. A plurality of objects within the chamber move in response to the water flow and abrasively clean the at least one electrode. Preferably, the sensor system includes a chlorine sensor having at least two electrodes. The electronics subsystem applies a first differential voltage between the two electrodes during a measurement interval and then applies a second differential voltage between the two electrodes during an interval following the measurement interval.
G01N 27/08 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a liquid which is flowing continuously
G01N 27/06 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a liquid
A sensor system that measures at least one parameter of water includes an electronics subsystem and includes a sensor housing electrically and mechanically coupled to the electronics subsystem. The sensor housing encloses a chamber that receives water via at least one inlet and that releases water via at least one outlet. At least one sensor has at least one electrode exposed to water in the chamber. A flow generator causes water to flow through the chamber. A plurality of objects within the chamber move in response to the water flow and abrasively clean the at least one electrode. Preferably, the sensor system includes a chlorine sensor having at least two electrodes. The electronics subsystem applies a first differential voltage between the two electrodes during a measurement interval and then applies a second differential voltage between the two electrodes during an interval following the measurement interval.
G01N 27/08 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a liquid which is flowing continuously
G01N 27/06 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a liquid
A sensor system that measures at least one parameter of water includes an electronics subsystem and includes a sensor housing electrically and mechanically coupled to the electronics subsystem. The sensor housing encloses a chamber that receives water via at least one inlet and that releases water via at least one outlet. At least one sensor has at least one electrode exposed to water in the chamber. A flow generator causes water to flow through the chamber. A plurality of objects within the chamber move in response to the water flow and abrasively clean the at least one electrode. Preferably, the sensor system includes a chlorine sensor having at least two electrodes. The electronics subsystem applies a first differential voltage between the two electrodes during a measurement interval and then applies a second differential voltage between the two electrodes during an interval following the measurement interval.
A sensor system that measures at least one parameter of water includes an electronics subsystem and includes a sensor housing electrically and mechanically coupled to the electronics subsystem. The sensor housing encloses a chamber that receives water via at least one inlet and that releases water via at least one outlet. At least one sensor has at least one electrode exposed to water in the chamber. A flow generator causes water to flow through the chamber. A plurality of objects within the chamber move in response to the water flow and abrasively clean the at least one electrode. Preferably, the sensor system includes a chlorine sensor having at least two electrodes. The electronics subsystem applies a first differential voltage between the two electrodes during a measurement interval and then applies a second differential voltage between the two electrodes during an interval following the measurement interval.
G01N 27/06 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a liquid
G01N 27/08 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a liquid which is flowing continuously
A sensor system that measures at least one parameter of water includes an electronics subsystem and includes a sensor housing electrically and mechanically coupled to the electronics subsystem. The sensor housing encloses a chamber that receives water via at least one inlet and that releases water via at least one outlet. At least one sensor has at least one electrode exposed to water in the chamber. A flow generator causes water to flow through the chamber. A plurality of objects within the chamber move in response to the water flow and abrasively clean the at least one electrode. Preferably, the sensor system includes a chlorine sensor having at least two electrodes. The electronics subsystem applies a first differential voltage between the two electrodes during a measurement interval and then applies a second differential voltage between the two electrodes during an interval following the measurement interval.
G01N 27/06 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a liquid
An amperometric sensor includes a first electrode, a second electrode and a reference electrode. The sensor further includes a switch to selectably electrically connect the first electrode as a working electrode and to electrically connecting the second electrode as an auxiliary electrode during a first time interval. During a second time interval, the switch electrically connects the first electrode as the auxiliary electrode and electrically connects the second electrode as the working electrode. The switching of the two electrodes is repeated continuously as amperometric measurements are performed. Preferably, the sensor includes an ultrasonic transducer proximate the working electrode and the auxiliary electrode to clean the electrodes.
G01N 27/26 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variablesInvestigating or analysing materials by the use of electric, electrochemical, or magnetic means by using electrolysis or electrophoresis
C02F 1/76 - Treatment of water, waste water, or sewage by oxidation with halogens or compounds of halogens
C02F 1/461 - Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
8.
System for maintaining pH and sanitizing agent levels of water in a water feature
A system automatically maintains at least one of a pH level and a sanitizing agent level of water in a water feature. The system includes a sensor assembly responsive to at least one of a pH level of the water and a sanitizing agent level of the water. The system further includes a controller which generates control signals in response to signals from the sensor assembly. The system further includes at least one of a first source containing an sanitizing agent material and a second source containing a pH-modifying material. The system further includes a third source comprising a valve assembly and a third container containing a liquid calibrant material. The valve assembly is responsive to at least a portion of the control signals from the controller by selectively allowing the calibrant material to flow from the third container through the sensor assembly to the water feature.
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