How to calibrate the device correctly
one bag powder dissolved in 250ml pure water,when you need to do the calibrate,take some solution,the rest of the solution can Sealed preservation 1 month
1. Turn on the machine, put the PH818 in pure water, clean it and wipe it with a cloth. Press and hold the calibration button, put the machine into the debugged PH4.00 solution, stir it for a few seconds, and let it stand for a few seconds until the machine screen appears. "PR5”
2. When the machine number becomes 6.86, take out the machine, clean it in pure water, wipe it with a cloth, put it into the debugged PH6.86 solution, stir it for a few seconds, and let it stand for a few seconds until the machine screen appears “PR5”
3. When the machine number becomes 9.18, take out the machine, clean it in pure water, wipe it with a cloth, put it into the debugged PH9.18 solution, stir it for a few seconds, and let it stand for a few seconds until the machine screen appears “PR5”
4. The machine is restored to the state when it was turned on, and the calibration is completed.
Professional Pen Type PH Meter Portable PH Water Quality Tester:
