User manual HANNA INSTRUMENTS HI 8043

[. . . ] 7 Dissolved Oxygen Calibration . . . . . . . . . . . . . . . . . . . . . 9 Temperature Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Taking Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Probe & Membrane Maintenance . . . . . . . . . . . . . [. . . ] - Whenever the electrolyte or membrane is changed and after cleaning the electrode. - After excessive use in aggressive solutions. Accessories: - 200 cc of HI 7040 solution - 1 bottle of HI 7041 solution Procedure for calibration at sea level: · If you are starting from STB the "OFF" position, switch OFF to "STB" and wait 30 minutes for complete polarization of the probe before proceeding to the calibration procedure. ZERO CALIBRATION: · Switch from "STB" position to "O2" position. · Remove the protective cap and immerse the probe in the HI 7040 zero oxygen solution and wait for approximately 5 minutes. The indications given by the instrument must fall to stabilization levels. If the probe has not been sufficiently polarized, the readout will continue to fluctuate. °C O2 STB OFF °C O2 · 9 · In this case, switch back STB °C O to "STB" position, place OFF the protective cap and wait for a few hours for complete polarization before proceeding. Using a small screwdriver, turn the Zero Calibration screw until the display reads zero. 2 ZERO SLOPE °C · If the zero point is passed, "1" will appear on the display. If you cannot get zero reading the probe is probably defective, in which case you should check the membrane, electrode and electrolyte solution (see below). Rinse the probe thoroughly with normal tap water after the zero calibration has been completed. SLOPE CALIBRATION: In order to perform a highly accurate calibration, take a B. O. D. bottle and then fill with water to a depth of 1 or 2 cm (½ or ¾"), then seal the bottle with the probe inside. If this calibration is to be carried out with the bottle opened to air rather than according to the conditions described above, the margin of error is approximately 0. 1 ppm. · Switch the instrument to "°C", wait for readings to stabilize and then note the temperature of the water. 10 STB OFF °C O2 · · Refer to Table 1 on page 10 for the corresponding dissolved oxygen reading at that temperature. Switch to "O2" position STB °C and adjust the "Slope" OFF O trimmer until the correct reading is displayed; e. g. at 20. 5°C the trimmer should be adjusted until display reads 9. 08. 2 ZERO SLOPE °C CORRECTION FOR ALTITUDE EFFECT If the calibration is not performed at sea level a correction should be made for the difference in altitude according to Table 2 on page 11; e. g. if calibrated at 20. 5°C at an altitude of 300 m above sea level, the display should be adjusted to 9. 08 x 0. 96 = 8. 72. ZERO SLOPE °C CORRECTION FOR SALINITY EFFECT Another correction has to be performed if the sample presents significant salinity concentrations. In such case, the reading has to be adjusted according to Table 3 on page 12; e. g. This is to ensure that the oxygen-depleted membrane surface is constantly replenished. A moving stream will provide adequate circulation. To quickly check if the water speed is sufficient, wait for the reading to be stable and then move the D. O. If the reading is still stable, the measurement conditions are right, while if the reading increases the water movement is too low. [. . . ] If the repair is not covered by the warranty, you will be notified of the charge for repair or replacement. If the instrument is to be returned to Hanna Instruments, obtain a Return Goods Authorization from the Customer Service Department first and then send it with shipment cost prepaid. When shipping any instrument, make sure it is properly packaged for complete protection. All rights are reserved. Reproduction in whole or in part is prohibited without the written consent of the copyright owner. [. . . ]