Patent ID: 7459067

Claim:
A semi-permanent reference electrode for use in field applications, said semi-permanent reference electrode being associated with a working electrode to form a cell, said semi-permanent reference electrode and said working electrode being used in a system with a voltmeter, said voltmeter used to measure the potential difference between said working electrode and said semi-permanent reference electrode, and a power supply, said power supply being used to supply a potential to said working electrode, said semi-permanent reference electrode comprising: an electrode body forming an electrode internal chamber; a fill solution contained within said electrode internal chamber, said fill solution being a saturated salt solution with a constant pH formed from a solid salt, wherein said solid salt is hygroscopic, hydrolyzable and has a low deliquescence point; a wire situated within said electrode internal chamber for making contact with said fill solution; a cap removeably situated within said electrode inner chamber; a porous plug removeably situated within said electrode inner chamber; and an opening in said cap for passage of moisture from the environment into said electrode inner chamber; wherein said fill solution does not dry in field applications because said fill solution can draw moisture from the environment to maintain itself in solution.