What is a TDS Meter?

What is TDS?

TDS is the abbreviation of Total Dissolved Solids, it is also called total dissolved solids. Its unit of measurement is mg/L. TDS indicates the milligrams of dissolved solids in 1 liter of water. The higher the TDS value, the more dissolved substances contained in the water. Total dissolved solids refers to the total amount of all solutes in water, including inorganic and organic content. Under normal circumstances, you can roughly understand the salt in the solution based on the conductivity value. In general, the higher the conductivity, the higher the salt content, and the higher the TDS.

In inorganic substances, in addition to ionic components, there may also be molecular inorganic substances. Since organic matter and molecular inorganic matter contained in natural water are generally not considered, the salt content is generally called total dissolved solids. However, in specific water, the TDS value does not effectively reflect the water quality. For example, in electrolyzed water, since the [OH]- and other charged ions in the electrolyzed water increase significantly, the corresponding conductivity increases abnormally. For example, the original pure water with a TDS of 17, after electrolysis by a water electrolysis machine, the TDS value of the alkaline water obtained is about 300.

What is a TDS Meter?

The TDS meter is a small handheld device used to indicate the total dissolved solids in a solution (usually water). Since dissolved ionized solids (such as salts and minerals) increase the conductivity of the solution, the TDS meter can measure the conductivity of the solution and estimate the TDS value based on the measured value. Some TDS meters can test the salinity simultaneously. For example, a 0~10000PPM TDS meter has a salinity testing range of 0.01%~25% , so it is not only a TDS meter, but also a salinometer.

It should be noted that TDS meter does not measure pollutants. Although TDS meter is often used as a water quality testing instrument, it does not directly tell you whether the water is healthy. In fact, some healthy minerals in the water, such as potassium, magnesium, calcium, etc., can cause the TDS meter to suddenly rise. Therefore, using TDS meter for water filters with mineralizers may have the opposite effect to your expectations. Your water may also contain heavy metals such as lead, or other pollutants such as pesticides, drugs, and hexavalent chromium. Although it is a kind of water quality tester, TDS meter cannot detect these pollutants.

TDS Meter Working Principle

The TDS meter provides a reading by measuring the conductivity of the dissolved ions in the solution, and its unit is PPM (one in one million). The TDS meter reads the reading and converts it into an estimated value of TDS through a formula. The TDS meter can measure conductivity. After obtaining the conductivity or EC, it converts it to a TDS number. Some TDS meters provide actual EC readings and TDS values.

The dissolved solid is charged. Pure water H₂O or distilled water does not conduct electricity, while the electronic charges that constitute minerals are conductive. Water with more minerals is more conductive than water without minerals. If the TDS meter is immersed in completely distilled water, the result of trace minerals in the water will be zero or a number close to zero.

Common Sense of Using a TDS Meter

1. When the TDS meter is used in purified water and mineral water after a long period of time, its TDS value will rise to a high value compared to the beginning, and the total number of co-virus and bacterial colonies will increase accordingly. At this time, the water should not be used without boiling, otherwise it will affect your health. For products of the water purifier category, TDS meter is generally used for water quality testing of pure water machines, not for testing of mineral water machines.
2. The TDS value of pure alcohol is 0. If it is greater than 0, it means impure.
3. TDS is the dissolved amount of total solids. If the TDS meter shows a value of 100, it means that each liter of water contains 100 mg of impurities.
4. Users living on the third floor or above will be supplied with water from the top-level storage tank, which is likely to cause secondary pollution. TDS meter should be used frequently to detect changes in TDS values, and the property management department should be urged to clean regularly.
5. When it is not clear how much washing powder should be put in the washing machine, TDS meter can be used to detect and digitize the experience. After the washing machine completes the cleaning process, it should be tested with a TDS meter before draining. If the indicated value is the same as tap water, it can be regarded as clean. If the indicated value exceeds the tap water, the amount of washing powder should be reduced.
6. After the fruits and vegetables are soaked in water, they can be tested with TDS meter. If the displayed TDS value is too high, there may be chemical contamination, so attention should be paid.
7. In the process of swimming in public swimming pools, TDS meter can be used to test the changes in pool water cleanliness. If the indicated value is too high, attention should be paid.
8. If the TDS value of the deep well water is higher than 300, it means that the impurity content is too high.
9. In each region and city, the TDS value will be different due to different pipelines and water sources.
10. The flower fertilizer can be measured with TDS meter after being prepared according to regulations for the first time, and saving the displayed value can facilitate future preparation.
11. Using TDS meter to measure goldfish tank water can understand its cleanliness. If the value increases too much, the water should be changed in time.
12. The TDS meter can be used to measure the water used in aquaculture for future preparation and testing.