User manual HANNA INSTRUMENTS HI 9810

[. . . ] 5 OPERATIONAL GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 pH CALIBRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 EC/TDS CALIBRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 TEMPERATURE COMPENSATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] After cleaning, it is recommended to rinse the electrode with some of the sample to be measured. AFTER MEASUREMENTS After measurements have been completed, the instrument should be switched off and the probe cleaned and covered with the protective cap. 6 7 p H CALIBRATION For greatest accuracy, frequent calibration of the instrument is recommended. The instrument should be recalibrated for pH: a) Whenever the electrode is replaced. d) Where extreme accuracy is required. EC/TDS CALIBRATION Accessories needed: · Use HI 7039 or HI 8039, 5, 000 µS/cm EC solution or HI 7032, 1382 ppm TDS solution. Note: the conversion between EC and TDS is made by a built-in circuit, hence it is requested to calibrate the meter only in EC or TDS range. The other range is thus automatically calibrated. PREPARATION Pour small quantities of pH 7. 01 (HI 7007 or HI 8007) or pH 4. 01 (HI 7004 or HI 8004) or pH 10. 01 (HI 7010 or HI 8010) solution into a clean beaker. To obtain accurate readings, use pH 7. 01 (HI 7007 or HI 8007) if you are going to measure neutral or close to neutral samples, pH 4. 01 ( H I 7004 or HI 8004) if you are going to measure acidic samples or pH 10. 01 (HI 7010 or HI 8010) for alkaline measurements. If you need to calibrate HI 9810 to NBS standards, use pH 6. 86 (HI 7006 or HI 8006) instead of pH 7. 01 and pH 9. 18 (HI 7009 or HI 8009) instead of pH 10. 01. PROCEDURE · Pour approximately 4 cm (1½") of a conductivity calibration solution (e. g. · Wait for a couple of minutes for thermal equilibrium to be reached. · Tap the combined electrode on the bottom, then shake it lightly while rotating to make sure no air bubbles remain trapped inside the probe. µS/cm. PROCEDURE · Switch the meter on after connecting the electrode and press pH to display pH measurement. · Remove the protective cap from the electrode, rinse and immerse it in the buffer and stir gently. · If the buffer solution is not at ambient temperature, take its temperature with a ChecktempC (or an accurate thermometer), e. g. Note: the electrode should be submerged approximately 4 cm (1½") into the solution. · Adjust the pH calibration knob until the LCD shows the pH value at the above temperature (see the pH versus temperature chart on page 10). · The pH calibration is now complete. 8 · Turn the EC/TDS calibration knob until the display shows the EC or TDS reading at 25 C. 9 p H VALUES AT VARIOUS TEMPERATURES For temperature compensation during calibration, please refer to the following chart. TEMP °C °F 0 32 5 41 10 50 15 59 20 68 25 77 30 86 35 95 40 104 45 113 50 122 55 131 60 140 65 149 70 158 4. 01 4. 01 4. 00 4. 00 4. 00 4. 00 4. 01 4. 02 4. 03 4. 04 4. 05 4. 06 4. 07 4. 09 4. 11 4. 12 6. 86 6. 98 6. 95 6. 92 6. 90 6. 88 6. 86 6. 85 6. 84 6. 84 6. 83 6. 83 6. 84 6. 84 6. 85 6. 85 pH VALUES 7. 01 9. 18 7. 13 9. 46 7. 10 9. 39 7. 07 9. 33 7. 04 9. 27 7. 03 9. 22 7. 01 9. 18 7. 00 9. 14 6. 99 9. 10 6. 98 9. 07 6. 98 9. 04 6. 98 9. 01 6. 98 8. 99 6. 98 8. 97 6. 99 8. 95 6. 99 8. 93 10. 01 10. 32 10. 24 10. 18 10. 12 10. 06 10. 01 9. 96 9. 92 9. 88 9. 85 9. 82 9. 79 9. 77 9. 76 9. 75 TEMPERATURE COMPENSATION The conductivity of an aqueous solution is the measure of its ability to carry an electrical current by means of ionic motion. It is affected by the type and number of ions in the solution and by the viscosity of the solution itself. The dependency of conductivity on temperature is expressed as a relative change per degree Celsius at a particular temperature, commonly as percent per C. Acids, alkalis and concentrated salt solutions have somewhat lower value, typically 1. 5%/ C. Since a small difference in temperature causes a large change in conductivity, it is necessary to compensate for conductivity readings at high and low temperature. HI 9810 automatically compensates for temperature differences with a built-in temperature sensor circuitry. With this compensation, the display shows the readings at 25 C (77 F). For instance, if the buffer temperature is 25 C, the display should show pH 4. 00 or 7. 00 or 10. 00. If the buffer temperature is 10 C, the display should show pH 4. 00 or 7. 10 or 10. 20. [. . . ] The metal band at the end of the electrode is sensitive to electrostatic discharges. The glass bulb at the end of the electrode is sensitive to electrostatic discharges. During operation, ESD wrist straps should be worn to avoid possible damage to the electrode by electrostatic discharges. Any variation introduced by the user to the supplied equipment may degrade the instrument's EMC performance. [. . . ]