Calibration
• Prepare three glasses with 250 ml of distilled water each
• Empty the 6.86 solution into the first glass, 4.00 into the second glass, 9.18 into the third glass
• Shake gently to dissolve the calibration solutions
• Switch on the instrument
• Immerse the electrode in the buffer solution with pH 6.86 (at a temperature of 25 ° C)
• Press the Cal key, the digital display starts flashing, when you stop the calibration at pH 6.86 is completed
• Rinse the electrode with distilled water and dry it with soft paper
• Immerse the electrode in the buffer solution with pH 4.00
• Press the Cal key twice, the digital display starts flashing, when it stops the calibration at pH 4.00 is completed
• Rinse the electrode with distilled water and dry it with soft paper
• Immerse the electrode in the buffer solution with pH 9.18, wait a few seconds for it to stabilize; if the calibration has been done correctly the display will show a pH of 9.17 - 9.19.