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TDS 342 Calibration Solution [HM Digital]
In order to ahieve optimal performance, re-calibrate your meters periodically. Re-calibrate if testing TDS or conductivity levels in wide or different ranges.
· NaCl calibration solution, available in 342 ppm or 1000 ppm.
· Comes in lightweight HDPE plastic bottles.
· Sealed with a coated foam liner.
· NaCl solution
· Available in 342 ppm or 1000 ppm
· 3 oz. bottles (88.7 ml)
342 NaCl =
362 as KCl ; 478 as "442" ; 700 µS
1000 NaCl =
1060 as KCl ; 1450 as "442" ; 2000 µS
Benefits of HM Digital's TDS/EC Calibration Solutions
1. Laboratory quality NIST-traceable solutions
2. Solutions list alternate composition equivalents on the bottle labels.
3. Bottles are a convenient 3 oz. (88 ml) size - neither too big nor too small.
4. Bottles have a convenient wide mouth, allowing a user to simply insert the meter into a stable bottle (much easier to use than a wobbly Mylar pouch).
Additional Notes about TDS/EC Meters and Calibration
For best results, a meter should be calibrated as close as possible to what will be tested. For example, if the water you are testing is always around 150 ppm, then the meter should be calibrated as close to 150 ppm as possible.
If you are testing a range of values, the meter should be calibrated to the upper third of that range. For example, if you are testing RO water and tap water, and the RO water is approximately 0-10 ppm and the tap water is typically 400-500 ppm, the meter should be calibrated to approximately 350 ppm.
1. The average tap water in the U.S. is approximately 350 ppm (though this varies widely from location to location and can be anywhere from zero to greater than 1000 ppm). Therefore, HM Digital factory calibrates our meters to 342 ppm.
2. All HM Digital meters are factory calibrated. Therefore, calibration is not necessary out of the box. Typically, with proper care and normal usage, HM Digital TDS and EC meters will retain their calibration for at least a year.
3. Only calibrate a meter if you are sure you need to. As a general rule of thumb, if you are unsure if you need to calibrate, you probably don't. It is always safer not to calibrate than to attempt doing so.
4. Though calibrating correctly will improve results, for normal usage and ranges, the difference will not be dramatic.
5. Never calibrate a meter to the air.
6. Never calibrate a meter to distilled water.
7. Never calibrate a meter to tap water, or any water or solution that is not certified.
8. HM Digital calibration solutions have a shelf life of approximately 1 year unopened.
9. Once opened, HM Digital calibration solutions have a shelf life of approximately 6 months, if properly stored and not contaminated.
10. All calibration solutions should be stored in a cool place, out of the heat and sun.
11. Contamination can occur if dipping a meter in water or a second calibration solution with a different value, and then dipping that meter back into the first calibration solution. The droplets from the water and other calibration solution will change the value. If testing between water and a calibration solution, always let the meter air dry or spray it with a compressed air can to avoid contamination.
9L x 4.5w x 4.5H