Instructions for use of PH-02:1 Product parameters:Measurement range: 0.00-14.00PHAccuracy error: 0.01PHResolution: 0.01PHWorking temperature: 0 -80 Calibration method: 2-point automatic calibrationElectrode: glass bubbleTemperature compensation: ATC automatic temperature compensationNet weight: 48gBattery: 2 * 1.5V (LR44 button cell)External dimensions: 155mm * 29mm * 16mmOuter box size: 167mm * 52mm * 30mm2 Usage:Cut the plastic bag, pour the powder into a 250ML volumetric flask, wash the inner wall of the plastic bag with a small amount of CO2 free distilled water, dilute it to the scale and shake it up.The shelf life of the powder is 2 years.The calibration solution can be reused without contamination. The shelf life after mixing with water is about 6 months.After mixing the calibration powder and turning it into calibration solution, proceed as follows Calibration solution usage method:Wash the pH meter electrode thoroughly with pure water (2-3 times)1. Immerse the pH electrode in a mixed phosphate standard buffer solution with a pH value of 6.86 (at 25 ) and gently shake it.2. Use a small screwdriver to adjust and calibrate the potentiometer until the displayed value is consistent with the ph value of standard buffer solution at ambient temperature.3. First clean the electrode with pure water, and then insert the electrode into a pH 4.00 standard buffer solution of potassium hydrogen phthalate for calibration.4. After about two minutes, the displayed value should be within the allowable range of error compared to the pH value of the buffer solution.The so-called two-point calibration refers to using two specifications of calibration solutions for calibration, while three-point calibration refers to using three specifications of calibration solutions for calibration. Generally, calibration starts from 6.86. Then use 4.00.3 Operating Steps1. Remove the protective cover.2. First, clean the electrode of the pH meter with distilled water and wipe the electrode dry with filter paper.3. Turn on the switch located on the battery compartment.4. Insert the pH meter into the measured liquid until the liquid reaches the "immersion line". If conditions permit, the solution can be immersed to a position slightly higher than the "immersion line".5. Gently stir the solution and wait for about two minutes. Read the displayed value.6. After use, clean the electrodes, turn off the switch, and put on a protective cover.