Patent ID: 7110887
Filing Date: 2006-09-19
Classification: G01N

Abstract:
1. A residual chlorine meter comprising: a detection section; an input section; a calibration factor computation data storage section; a calibration factor computation section; a calibration factor storage section; a residual chlorine concentration computation data storage section; and a residual chlorine concentration computation section; wherein the detection section is for detecting a pre-calibration residual chlorine reaction amount and an on-measurement residual chlorine reaction amount of sample water; wherein the input section is for selecting a calibration standard residual chlorine concentration of the sample water; wherein the calibration factor computation data storage section is for storing, in advance, a standard table showing a relationship between a residual chlorine concentration and a residual chlorine reaction amount and including a selected standard residual chlorine concentration that indicates a borderline at which the trend in the relationship changes prominently; a computing equation for computing a calibration factor when the concentration is lower than the selected standard residual chlorine concentration, based on the pre-calibration residual chlorine reaction amount and the calibration standard residual chlorine concentration; and a computing equation for computing a calibration factor, when the concentration is equal to or higher than the selected standard residual chlorine concentration, based on the pre-calibration residual chlorine reaction amount and the calibration standard residual chlorine concentration; wherein the calibration factor computation section refers to the standard table stored in the calibration factor computation data storage section to specify, as a calibration standard residual chlorine reaction amount, a residual chlorine reaction amount corresponding to a residual chlorine concentration corresponding to the calibration standard residual chlorine concentration of the sample water selected via the input section, and substitutes the specified calibration standard residual chlorine reaction amount and the pre-calibration residual chlorine reaction amount of the sample water into the computing equation for computing a calibration factor for when the concentration is lower than the selected standard residual chlorine concentration and into the computing equation for computing a calibration factor for when the concentration is equal to or higher than the selected standard residual chlorine concentration, to compute the calibration factor when the concentration is lower than the selected standard residual chlorine concentration and the calibration factor when the concentration is equal to or higher than the selected standard residual chlorine concentration; wherein the calibration factor storage section stores the calibration factor for when the concentration is lower than the selected standard residual chlorine concentration and the calibration factor for when the concentration is equal to or higher than the selected standard residual chlorine concentration that have been computed by the calibration factor computation section; wherein the residual chlorine concentration computation data storage section is for storing, in advance, a standard table showing a relationship between a residual chlorine concentration and a residual chlorine reaction amount and including a pre-calibration selected standard residual chlorine reaction amount corresponding to a selected standard residual chlorine concentration that indicates a borderline at which the trend in the relationship changes prominently; a computing equation for computing a post-calibration selected standard residual chlorine reaction amount based on the pre-calibration selected standard residual chlorine reaction amount, the on-measurement residual chlorine reaction amount, and the calibration standard residual chlorine reaction amount; a computing equation for computing a post-calibration residual chlorine reaction amount when the concentration is lower than the selected standard residual chlorine concentration based on the on-measurement residual chlorine reaction amount and the calibration factor when the concentration is lower than the selected standard residual chlorine concentration; and a computing equation for computing a post-calibration residual chlorine reaction amount when the concentration is equal to or higher than the selected standard residual chlorine concentration based on the on-measurement residual chlorine reaction amount and the calibration factor for when the concentration is equal to or higher than the selected standard residual chlorine concentration; and wherein the residual chlorine concentration computation section refers to the standard table stored in the residual chlorine concentration computation data storage section to specify a pre-calibration selected standard residual chlorine reaction amount, substitutes the specified pre-calibration selected standard residual chlorine reaction amount, the calibration standard residual chlorine reaction amount specified by the calibration factor computation section and the on-measurement residual chlorine reaction amount of the sample water into the computing equation for computing a post-calibration selected standard residual chlorine reaction amount that has been stored in the residual chlorine concentration computation data storage section to compute the post-calibration selected standard residual chlorine reaction amount, substitutes the on-measurement residual chlorine reaction amount of the sample water and the calibration factor for when the concentration is lower than the selected standard residual chlorine concentration into the computing equation for computing a post-calibration residual chlorine reaction amount when the concentration is lower than the selected standard residual chlorine concentration to compute the post-calibration residual chlorine reaction amount when the concentration is lower than the selected standard residual chlorine concentration, when the computed post-calibration selected standard residual chlorine reaction amount is higher than the on-measurement residual chlorine reaction amount of the sample water, substitutes the on-measurement residual chlorine reaction amount of the sample water and the calibration factor for when the concentration is equal to or higher than the selected standard residual chlorine concentration into the computing equation for computing a post-calibration residual chlorine reaction amount when the concentration is equal to or higher than the selected standard residual chlorine concentration to compute the post-calibration residual chlorine reaction amount when the concentration is equal to or higher than the selected standard residual chlorine concentration, and when the computed post-calibration selected standard residual chlorine reaction amount is lower than the on-measurement residual chlorine reaction amount of the sample water, refers to the standard table stored in the residual chlorine concentration computation data storage section to specify, as a post-calibration residual chlorine concentration, a residual chlorine concentration corresponding to the computed post-calibration residual chlorine reaction amount when the concentration is lower than the selected standard residual chlorine concentration or the computed post-calibration residual chlorine reaction amount when the concentration is equal to or higher than the selected standard residual chlorine concentration.