초록 ▼

The instant invention is a device and method for its use which includes the addition of a deviation compensation function effective to automatically adjust the offset used in time-based proportional control. Inclusion of this improvement finds particular utility in situations like public pools where

The instant invention is a device and method for its use which includes the addition of a deviation compensation function effective to automatically adjust the offset used in time-based proportional control. Inclusion of this improvement finds particular utility in situations like public pools where daily bather load varies depending on weather and other unpredictable factors.

대표청구항 ▼

1. A process for time-based proportional control of chemical values in a water treatment system wherein a measured signal value is generated, comprising the steps: selecting an offset sensitivity value; and calculating a setpoint offset value (SOV) to determine said measured signal value; where

1. A process for time-based proportional control of chemical values in a water treatment system wherein a measured signal value is generated, comprising the steps: selecting an offset sensitivity value; and calculating a setpoint offset value (SOV) to determine said measured signal value; wherein said measured signal value approximates an ideal proportional control response, and wherein said setpoint offset value is calculated according to the formula SOV=(SD/PB)*OS*PB where SD equals the sustained deviation from setpoint, PB equals Proportional Band Width, and OS equals Offset Sensitivity Value. 2. In a process for time-based proportional control of chemical values in a water treatment system wherein a measured signal value is generated, the improvement comprising: modifying said measured signal value to be within a range defined by a particular proportional band width; verifying that said signal value likes within a hysteresis value about a particularly defined setpoint; measuring said signal value to confirm that said signal value is steady or retreating from said setpoint during a selected time duration; selecting an offset sensitivity value; and calculating a setpoint offset value (SOV) according to the formula SOV=(SD/PB)*OS*PB where SD equals the sustained deviation from setpoint PB equals Proportional Band Width OS equals Offset Sensitivity Value; wherein said measured signal value approximates an ideal proportional control response. 3. A process in accordance with claim 2 wherein: said particular proportional band width is between about 5 and 500 mV. 4. A process in accordance with claim 2 wherein: said particular proportional band width is between about 0.1 and 5.0 pH units. 5. A process in accordance with claim 2 wherein: said particular proportional band width is between about 10 and 5000 microsiemens. 6. A process in accordance with claim 2 wherein: said time base is between about 15 and 600 seconds. 7. A process in accordance with claim 2 wherein: said selected time duration is a multiple of the time base. 8. A process in accordance with claim 2 wherein: said hysteresis value is between about 0 and 10 mV. 9. A process in accordance with claim 2 wherein: said hysteresis value is between about 0 and 1.0 pH units. 10. A process in accordance with claim 2 wherein: said particular proportional band width is between about 0 and 1000 microsiemens. 11. A process in accordance with claim 2 wherein said setpoint is between about 150 and 780 mV. 12. A process in accordance with claim 2 wherein: said setpoint is between about 2 and 12 pH units. 13. A process in accordance with claim 2 wherein: said setpoint is between about 1000 and 4000 microsiemens. 14. A process in accordance with claim 2 wherein: said offset sensitivity value is within the range of about 0 and 100 percent.