How to work with TDS meter

The operating principle of the TDS meter is based on the ability of the electrical conductivity of water. When immersed in water, the electrodes of the device between an electric field. Conducts current only dissolved in the water connection (water itself is not); the amount of these impurities and shows salimeter.
TDS (Total Dissolved Solids) - is the total number of substances dissolved in water and the elements. Indications are presented as units of ppm (Parts Per Million, 1 ppm = 1 mg / L)
There is a correlation between the electric conductivity of water quantity of dissolved substances (usually of hardness salts); This allows you to securely and reliably, quickly and cheaply to determine the general level of salinity using TDS meter.
TDS-metry reverse osmosis systems
The input filter of back osmosis water enters varying degrees of salinity. In our Kharkov almost all the salts in tap water - hardness salts. CBS showing an average of 400 - 500 ppm (remember, 1 ppm = 1 mg / l; sanitary services are working with a different scale of conformity - mmol / liter, mEq / L. To convert ppm in mEq / L, it is necessary readings TDS multiply by a factor of 0.02. Thus Kharkov stiffness tap water is 8 to 10 mEq / L).
After cleaning the water as the new constant diaphragm (the main element of a reverse osmosis filter) TDS readings are 8 -35 ppm. Up to 50 -60 units flavor quality of the treated water is stored; while figures above 80 ppm of the membrane should be replaced.
The degree of mineralization of residual water after cleaning th REVERSE osmosis is dependent on a number of reasons:
- The quantity of salts in the water inlet;
- The water temperature;
- Incoming water pressure on the diaphragm;
- Selectivity of the membrane;
- The quality of the structure and elements of reverse osmosis;
- The state of the membrane (in time the top layer of the membrane zasolivaetsya and thinner from the effects of chlorine).
Reverse osmosis systems are used not only at home. Aquarists, pharmacology and production technology operate with different units of measurements. Below is a table of correspondence between the various units of the rigidity of some countries.

The first article was published on our website Osmosis Kharkiv 02.08.2015