What is a TDS METER?
A healthy life begins with drinking quality water that is free from contaminants. We often drink water without knowing the percentage of dissolved solids present in it. However, we can measure it with a help of a device. TDS is the abbreviated form of Total dissolved solids. TDS Meter, a handheld device primarily represents the different contents that exist in liquids especially water. Therefore, we can say, these meters are used to measure the amount of total dissolved solids present in water. It measures the conductivity of the liquids and gives the TDS reading. Besides the H2O molecule, TDS can be anything starting from dissolved compounds, minerals, salts, or micro granular or ionized particles. These dissolved particles are considered as contaminants, however; measuring the water with TDS meters is the first step taken towards water purification.
What does TDS signify?
Precipitation and the rivers that flow along the mountain ranges are the main sources of water on the planet. As the river flows through the rocks and the soils, they pick up salt and minerals in the process. There are different types of minerals like magnesium, calcium, and sodium that a river picks up while it flows. Although, on the one hand, the addition of these minerals improves the taste of water while on the other hand, this process raises the pH level in water. Water, if taken in raw form poses a threat to the mankind. Hence, the water purifiers are required to rule out the presence of these harmful chemicals.
A water purifier technician uses a small hand held device to check whether or not the water is pure and safe for drinking. The TDS meter readings estimate the presence of TDS in water. This device looks like a thermometer and it is very easy and convenient to use.
Let us try to understand what is a TDS meter and what role does it play?
As mentioned above, to rule out the presence of dissolved materials in water, these meters are used. These meters can be used easily and conveniently.
The procedure involved is mentioned below in a step by step approach.
● Take a clean cup and collect some water in it.
● Remove the cap of your TDS device and switch it on.
● At the end of the meter, you will find two electrodes. Submerge these electrodes in water however; do not submerge the entire electrode. If submerged entirely, you might end up damaging them.
● Make sure there are no bubbles in the water the place where the electrodes are submerged. If there is any, shake if off lightly by stirring the water with the meter.
● Now, allow five seconds until the reading gets stabilized. You will be able to view the readings once it gets stabilized.
● Once done, do not forget to remove it from water and shake off the excess water if any.
● Place the cap and store the meter safely.
● You will get a number that will flash on the screen as soon as you bring the device in contact with water. This number would tell you the number of solids present in water.
Measurement of TDS with TDS meters:
Explained above, is a simple and step by step process of measurement with the help of this device. However, we should have an in-depth understanding of the measurement process which is detailed below.
TDS devices are a cheaper way to measure the presence of dissolved materials in water. These devices are very lightweight and flexible. Due to their flexibility, they can be used for both tap and filtered water.
However, one important thing you should consider while using these TDS device is they do not actually measure the TDS levels in particular; on the contrary, it measures the electrical conductivity of the water. It estimates the presence of positively and negatively charged ions in water. The electrical conductivity of drinking water is zero, therefore; if the readings show anything above zero, then it indicates towards the presence of dissolved substances in water. The most frequent dissolved solids in water is salt and it is an electrolyte. The salt increases electrical conductivity of water. Unlike salt, sugar isn’t considered as an electrolyte and hence it does not increase the EC of water.
One more vital thing to consider is water consists of different types of dissolved substances in varying levels. To make the process simpler, The TDS devices use conversion factors that range from 0.4 to 1.0. With the help of the conversion factor, the EC is converted to the estimated level of TDS.
The efficiency of RO Membranes:
The reverse osmosis (RO) membranes can be tested efficiently with TDS devices. The RO Membranes are measured with the same process that is used to test the TDS concentrations in water. The process is very simple and can be carried out easily which is mentioned as under:
● First, measure the TDS levels of the water before it goes through the process of reverse osmosis.
● Once the test is done, make a note or save the number that is on the display.
● Next, measure the TDS level of water after it goes through the process of reverse osmosis.
● Once you have the result, compare both concentration levels.
● You will find the TDS concentration levels of water after it undergoes reverse osmosis are almost ten times lower when compared with the TDS concentrations of the tap water.
● After you run the tests, you will be able to understand the efficiency of the RO membranes in lowering the TDS concentrations present in water.
Safety Levels of water:
● The acceptable standards of the levels of TDS concentrations have been set by the Environmental Protection Agency (EPA). The level is 500 parts per million. It should be noted here that ppm can also be expressed in milligrams per unit volume of water. Therefore, it is extremely important to measure the acceptable levels of TDS concentrations in water before any ingestion. It has been found that most of the water supplies exceed this level. If the TDS levels are more than 1000 ppm, then the water is considered to be unsuitable for drinking. High levels of TDS in water indicate potential water threats and concerns that need immediate investigation and intervention.
● Sometimes, high TDS level indicates the presence of high percentages of chlorine, sodium, potassium, and ions in water which do not have many side effects. However, it becomes a matter of concern when concentrates like cadmium, lead arsenic, and nitrate are found in water because these elements have negative effects on our body. That is why it is always recommended to check the TDS concentration levels in water to rule out any such adverse health effects.
Understanding the Results of the TDS device
A water purifier technician is the best person who can help you understand what does the results indicate that are flashed on the TDS meter. However, having prior knowledge can always help you understand better.
● The result that is considered the best is 0 ppm.
● These meters are unable to read the presence of non-ionic substances like sugar and thus the presence of sugar won’t contribute to the readings.
● Ideally, the purity of water is measured with inline TDS devices after it passes through several stages of filtration.
● As water passes through the different filter stages, the dissolved solids are removed and the water becomes totally free from contamination or a has very low level of contaminated particles.
● As mentioned above, the EC value of drinking water should range between 0.5 to 0.8 mS/cm and a typical TDS value should be between 250 to 400 ppm.
● For the purpose of reference, you should know the EC value of natural seawater is 53.0 mS/cm.
● If you consider ultrapure water, the EC value is less than 0.5 mS/cm.
Significance of Range in Determining Accuracy
For any analytical device like TDS meter, accuracy is the most vital thing. To determine accuracy, a TDS meter typically makes use of percentage. For low conductivity water, accuracy plays a big role as the values as close to zero are preferred.
Range is used to determine the accuracy of the TDS devices. The range is used to determine the maximum and the minimum limits for that specific meter.
Measuring water storages with TDS Devices
Besides measuring the EC value for your drinking water or tap water, you can also use this device to measure the water that is stored in your reservoir. Keeping a check on the reservoir water is also needed as the contaminants tend to make their way back if left unchecked for a long time.
The TDS devices are available in a variety of prices depending on the quality, application and accuracy of the device.
In conclusion, it can be said that the TDS meters are extremely essential tools for measuring the amounts of dissolved contaminants in water. Now that you have read and understood what is a TDS meter and the benefits of using it, use it extensively for tap water, reservoir, and aquariums.