Resistance and Resistivity

Approximate Resistivity of Water


T is ppm dissolved solids    R is resistance in ohm-cm.

Resistance of a Single Rod Anode to Earth(1)
Resistance of Multiple Vertical Anodes to Earth(1) (1)Derived from H.B. Dwight Equations Rough Indications of Electrolyte Corrosivity vs. Resistivity
Ohm – Cm Corrosivity
Below 100 Extremely corrosive
100 – 1,000 Very corrosive
1,000 – 2,500 Corrosive
2,500 – 7,500 Moderately corrosive
7,500 – 15,000 Mildly corrosive
Over 15,000 Progressively less corrosive