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Testing the Accuracy of Your TDS Meter

Total Dissolved Solids (TDS) meters are essential tools for measuring the concentration of dissolved solids in water. They are commonly used in various industries, including Agriculture, aquaculture, and water treatment. However, like any other measuring device, TDS meters need to be calibrated regularly to ensure accurate readings. Calibration involves adjusting the meter to match a known standard solution’s conductivity level. While calibration solutions are readily available in the market, there are instances when you may need to calibrate your TDS meter without access to these solutions.

One way to calibrate your TDS meter without a calibration solution is by using distilled water. Distilled water has a very low TDS level, close to zero. By using distilled water, you can set your TDS meter to read zero, ensuring that it is properly calibrated. To do this, simply fill a clean container with distilled water and immerse the TDS meter into it. Allow the meter to stabilize and then adjust the reading to zero using the calibration knob or button on the device.

Measurement range	N,N-Diethyl-1,4-phenylenediamine (DPD) spectrophotometry
Model	CLA-7112	CLA-7212	CLA-7113	CLA-7213
Inlet channel	Single channel	Double channel	Single channel	Double channel
Measurement range	Free chlorine\\uff1a(0.0-2.0)mg/L ,Calculated as Cl2;		Free chlorine:(0.5-10.0)mg/L ,Calculated as Cl2;
	pH\\uff1a\\uff080-14\\uff09\\uff1bTemperature\\uff1a\\uff080-100\\uff09\\u2103
Accuracy	Free chlorine:\\u00b110% or \\u00b10.05mg/L(take the large value),Calculated as Cl2;		Free chlorine:\\u00b110% or\\u00b10.25mg/L(take the large value),Calculated as Cl2;
	pH:\\u00b10.1pH\\uff1bTemperature\\uff1a\\u00b10.5\\u2103
Measurement Period	\\u22642.5min
Sampling interval	The interval (1\\uff5e999) min can be set arbitrarily
Maintenance cycle	Recommended once a month (see maintenance chapter)
Environmental requirements	A ventilated and dry room without strong vibration;Recommended room temperature\\uff1a\\uff0815\\uff5e28\\uff09\\u2103\\uff1bRelative humidity\\uff1a\\u226485%\\uff08No condensation\\uff09
Water sample flow	\\uff08200-400\\uff09 mL/min
Inlet pressure	\\uff080.1-0.3\\uff09 bar
Inlet water temperature range	\\uff080-40\\uff09\\u2103
Power supply	AC (100-240)V\\uff1b 50/60Hz
Power	120W
Power connection	The 3-core power cord with plug is connected to the mains Socket with ground wire
Data output	RS232/RS485/\\uff084\\uff5e20\\uff09mA
Size	HWD\\uff1a\\uff08800400200\\uff09mm

Another method to calibrate your TDS meter without a calibration solution is by using a homemade solution of known TDS level. This can be achieved by dissolving a precise amount of table Salt in a specific volume of distilled water. Table salt, also known as sodium chloride, has a known TDS level, making it a suitable substitute for a commercial calibration solution. By following a simple formula to calculate the TDS level of the homemade solution, you can calibrate your TDS meter accurately.

To create a homemade calibration solution, start by measuring out a precise amount of table salt, such as one gram. Dissolve the salt in a specific volume of distilled water, for example, one liter. By knowing the weight of the salt and the volume of water used, you can calculate the TDS level of the solution. Once the solution is prepared, immerse the TDS meter into it and adjust the reading to match the calculated TDS level.

It is important to note that homemade calibration solutions may not be as accurate as commercial ones, so it is recommended to use them as a temporary solution until you can obtain a proper calibration solution. Additionally, it is essential to clean and rinse your TDS meter thoroughly before and after calibration to ensure accurate readings.

In conclusion, calibrating your TDS meter is crucial for obtaining accurate measurements of dissolved solids in water. While commercial calibration solutions are preferred for their accuracy, there are ways to calibrate your TDS meter without access to these solutions. By using distilled water or a homemade calibration solution, you can ensure that your TDS meter is properly calibrated and providing reliable readings. Remember to follow the manufacturer’s instructions and guidelines when calibrating your TDS meter to maintain its accuracy and performance.