A TDS meter is a device that indicates the total amount of dissolved solids in water. The unit of measurement of TDS (Total Dissolved Solids) is ppm. 1 part per million of the total amount of substance in any mixture is called 1 PPM (English: parts per million).
To test water with a TDS meter, it is necessary to put the device into working condition and insert the part with metal tips into the water. The number that appears on the screen allows you to determine the amount of dissolved substances in the water. 1 ppm indicates how many milligrams of dissolved substances are in 1 liter of water.
The recommended ppm value for drinking water is a range of 0-60.