Electrical conductivity of water (EC)
Electrical conductivity (EC) is the measurement of the ability of water to conduct electricity. This ability depends directly on the concentration of conductive ions in the water. These conductive ions are formed due to the presence of inorganic substances such as chlorides, alkalis, carbonates and sulfides, and soluble salts. Most metals are extremely good at conducting electricity due to the large number of free electrons.
Definition of electrical conductivity (EC):
The amount of conduction or transmission of electricity or heat or sound by water is called water conductivity. Indicated by s or k.
Units of measurement of electrical conductivity of water:
Units in SI
Siemens per meter [S / m]
Units in the U.S
Millimos per centimeter [mmho / cm]
Differences between electrical conductivity and resistance:
Electrical conductivity is based on conductivity. Conductivity is the ability of a substance to transmit current. The units of measurement of electrical conductivity (EC) are Siemens / cm (S / cm, mS / cm, μS / cm, dS / m). For example, distilled water has an electrical conductivity of 0.55 μS / cm at 25 ° C.
Silver has the highest conductivity among metals: S / m 106 x63
Electrical resistance (ρ) is not the ability of a substance to transmit current and is focused on resistance. The units we use to measure electrical resistance include ohms.cm. For example, distilled water has a value of 16.18 Mohm.cm at 25 ° C.
Electrical conductivity values of different types of water:
Distilled water 0.05 µS / cm
Drinking water 800 to 200 /S / cm
Sea water 50 µS / cm
Rainwater or snow 100 to S / cm 2
Relationship between electrical conductivity and TDS:
TDS is a measure of the total number of solid ions in solution. Electrical conductivity (EC) is the measurement of the ion activity of a solution in terms of current carrying capacity. In dilute solution, TDS and EC are logically comparable.
A water sample TDS based on the measured EC value can be calculated using the following equation:
(TDS mg / l) = EC x 0.5 (dS / m or mmho / cm)
Or EC x 1000 x 0.5 (mS / cm)
* Laboratories of Abrizan Industrial Research Company located in Fars Science and Technology Park, using advanced devices and equipment, are able to measure various water parameters, including electrical conductivity (EC).