View Full Version : HM-1 Digital TDS Meter calibration?

12/28/2006, 03:26 PM
I received a new HM-1 Digital TDS Meter today, hooked up, seems to be working ok. But i also got 2 packes of "Hanna Instruments 1500 ppm TDS Solution. Is this used to calibrate the meter? and if so, do i need to use it initially, or just later on down the line? If/when i do need to use it, what do i do with it, there are no instructions on the package.

12/28/2006, 03:50 PM
IMO, the 1500ppm calibration solution is not very beneficial, since you will be measuring TDS in the 0 to few-hundred range. There are different ppm calibration solutions available, such as 342ppm found here: http://www.thefilterguys.biz/tds_meters.htm

The 342ppm solution would probably be better than 1500ppm, since that's closer to the range where you'll be testing.

To use the solution, you will want to make sure your meter is completely clean (i.e. triple rinsed in RO/DI water or equivalent), and then take the reading using the solution. The meter should have a calibration button you can press to enter into calibration mode, which you can then adjust the meter to match the solution. You may want to check with the company where the meter was purchased to see if they know how to calibrate it. I believe all HM TDS meters come "pre-calibrated".