Qiwei PHS-3CW pH meter (desktop microcomputer)

Introduction

Qiwei PHS-3CW pH meter (desktop microcomputer) adopts manual temperature compensation, the measurement accuracy is 0.01/0.1pH, and has data storage and extraction functions. The pH meter adopts imported high-quality integrated components, which makes the measurement of the pH meter more stable and reliable. The PHS-3CW meter needs to use three standard buffer solutions with pH values of 4, 6.86 and 9.18 for calibration.

product instructions

Calibration is required to use the PHS-3CW/PH timer. Before using the pH meter, it needs to be plugged in for preheating, then calibrated, and finally measured.

1. Preparation before use

1) Plug the power adapter into the 220V AC power supply, and insert the DC output plug into the power jack on the rear panel of the pH meter.

2) Install the electrode on the electrode holder, remove the short-circuit plug on the electrode socket of the pH meter, and plug in the electrode. (Note that the electrode plug should be kept clean and dry before use, and avoid contamination)

3) First turn on the power and press the switch button, and preheat for about 5 minutes.

2. Calibration

The PHS-3CW  pH meter needs to use three standard buffer solutions of 4.00, 6.86 and 9.18 for calibration.

Professional calibration is required before using the pH meter. The PHS-3CW/PHS-3CWB  pH meter uses three standard buffer solutions of 4.00, 6.86, and 9.18 for calibration. The standard buffer solutions used must be accurate and reliable to ensure the accuracy of subsequent measurement results.

1) Plug in the power supply and press the "Switch" button to turn on the machine. Unscrew  the short-circuit protective cover on the socket of the PHS-3CW pH meter, connect it to the plastic shell pH composite electrode, wash the electrode in pure water and dry it. Use a thermometer to measure the temperature of the pH buffer solution, and press the increase key "∧" or the decrease key "∨" to adjust the temperature value accurately.

2) Positioning calibration. Immerse the pH electrode in the pH6.86 buffer solution, stir it slightly, and then place it still. After the measured value is stable, press and hold the "calibration" button. When the CAL symbol is displayed on the LCD, release the "Calibration" button, the flashing 6.86 will be displayed first, the End symbol will be displayed after a few seconds, and then the pH calibration value will be displayed (the pH value displayed at this time varies with the temperature, for example, 25°C It will display 6.86 at 15°C, and 7.04 at 15°C. These are the values set in the chip, the same below). Indicates that calibration is completed and memorized.

3) Perform slope calibration I/calibration II successively. Where calibration I uses pH 4.00 buffer and calibration II uses pH 9.18 buffer. Operation method: Take out the pH electrode, wash it with pure water and dry it, then immerse the pH electrode in the pH4.00 (pH9.18) buffer solution, stir it a little and then place it still. After the measured value is stable, press " Hold down the "Calibration" key, and release it when the CAL symbol is displayed on the LCD, the flashing 4.00 (9.18) will be displayed first, the End symbol will be displayed after a few seconds, and then the pH calibration value will be displayed, indicating that the calibration is completed and memorized. After the calibration is completed, the slope percentage of the electrode in the linear segment will be automatically displayed.

Calibration instructions: Built-in smart chip, can use one-point, two-point or three-point automatic calibration, if the measurement accuracy is ≤0.1pH, just use a pH buffer solution for one-point calibration; if the measurement range is only in the acidic range (≤7pH ), you can choose pH7 and pH4 calibration; if the measurement range is only in the alkaline range (≥7pH), you can choose pH7 and pH10 calibration; Point calibration, which will make the measurement accuracy higher. For the pH electrode used for the first time, three-point calibration is required to adjust the slope of the instrument to be consistent with the pH electrode.

3. Measure the pH value of the solution

Use a thermometer to measure the temperature of the solution, then press the increase key ∧ or decrease key ∨ to adjust the temperature value of the instrument accurately, wash the pH electrode with pure water and dry it, then immerse it in the solution to be tested, stir it slightly and place it still, When the measured value is stable, the reading is the measured pH value.

Note: The closer the temperature of the measured solution is to the temperature of the calibration solution, the higher the measurement accuracy will be.

4. Measure the mV value

First press the "pH/mV" key to switch the "mV" file. Connect the PHS-3CW pH meter to the ORP electrode or ion electrode (required) and insert it into the solution to be tested. After a little stirring, place it still. After the measured value is stable, the reading is the measured ORP value or the ion electrode’s value. Potential value.

Pictures

Host x1, Buffer reagent x3, Encasement box x1

[Note] Because the manufacturer's packaging may be updated or upgraded, the detailed packaging list shall be subject to the latest standard configuration of the manufacturer.