ph meter with temperature compensation is an instrument used to measure acidity or alkalinity of a solution – also know as pH. pH is the unit of measure that describes the degree of acidity or alkalinity. It is measured on a scale of 0 to 14. Ph Sensor and Meter as a critical tool in water quality monitoring, widely used in drinking water, wastewater treatment and in the fields including mining and smelting, papermaking, paper pulp, textiles, fisheries, petrochemical industry, process of semiconductor electronic industry, and downstream engineering of biotechnology.