APPARATUS FOR MEASURING CHEMICAL LEVELS USING pH SHIFT

摘要

An apparatus for use in measuring the free chlorine level in a solution of halogenated pool/spa water includes a pH adjusting device for producing a first sample of said solution having a first selected pH and a second sample of said solution having a second selected pH, as well as a spectral analyzer for determining first and second ultraviolet light (UV) transmissivity values for each of the first and second samples. An electronic processor receives the first and second transmissivity values and determines the free chlorine or bromine level using those values.