This convertor can be used to convert for example Siemens per meter into TDS in PPM or MHO cm.
Siemens (S) is a unit of the electrical conductivity. The conductivity of water is measured within a certain distance thus the input is in S/cm or mS/cm. Other electrical conductivity units are Mho cm, CF (in America and Australia) en EC.
1) The term EC is used as a general term for Electrical Conductivity, on some conductivity meters, the actual conductivity is presented in "EC" units, where 1 EC corresponds with microS/cm.
Click here for a definition of water conductivity.