Cleaning & storage of EC/TDS/ Resistivity probes

Conductivity probes are simple to clean. Use a Q-tip with alcohol for dual pin sensors (amperometric) and a cloth with alcohol for 4 ring type sensors (potentiometric).

Probes can be stored dry in a clean environment.

EC vs TDS vs TDS442 in agriculture (fertilizers)

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Understanding mS, g/l, mg/l, ppm, ppt & converting from one to the other

Electrical conductivity is the ability of a solution to conduct an electric current. It can be used as an index of the total solids (TDS) in a water sample.

The unit of measure commonly used in Siemens per centimeter (S/cm). The conductivity of water is usually expressed as microSiemens/cm (µS/cm) which is 10-6 S/CM. The relation between conductivity and dissolved solids is approximately:

2 µS/cm = 1 ppm (which is the same as 1 mg/l)

The conductivity of water from various sources is

Absolute pure water - 0.055 µS/cm
Distilled water - 0.5 µS/cm
Mountain water - 1.0 µS/cm
Most drinking water sources - 500 to 800 µS/cm
Sea water - 56 mS/cm
Max for potable water - 1055 µS/cm

Some common conductivity conversion factors are

mS/cm x 1 000 = µS/cm
µS/cm x 0.001 = mS/cm
µS/cm x 1 = µmhos/cm
µS/cm x 0.5 = mg/l of TDS
mS/cm x 0.5 = g/l of TDS
mg/l TDS x 0.001 = g/l of TDS
mg/l TDS x 0.05842 = gpg TDS