[. . . ] 10 ELECTRODE MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 BATTERY REPLACEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 ACCESSORIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 WARRANTY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] The second point can be selected between 10. 0 (HI 70702) and 1000 ppm (HI 70701). If the sample to be tested has low ionic strength (below 100 ppm), use HI 70702 for the second point. Likewise, with sample concentrations above 100 ppm, use HI 70701 as the second calibration point. Prepare two calibration solutions by mixing sufficient quantity of 50% HI 70703 (100 ppm) and 50% HI 7023 (TISAB) solution in one beaker and then 50% of HI 70702 (10. 0 ppm) or HI 70701 (1000 ppm) solution and 50% HI 7023 (TISAB) in the other. · Attach the fluoride electrode (#3 on page 4), the reference electrode (#2) and the temperature probe (#1) to their respective connectors on top of the meter. Note: For best results, it is recommended to prepare two beakers for each calibration point: one beaker to rinse and the second one to calibrate. CALIBRATION PROCEDURE Note: If the fluoride electrode is new, or it has not been used for a few days, it must be soaked in a solution of HI 70702 (10 ppm of F-) for at least 3 hours prior to calibration. · Rinse the electrodes with deionized water and dry them attentively with a non-abrasive cloth. 8 MAGNETIC STIRRER HI 190M POWER ON OFF MAX SPEED Note: If the temperature probe is not connected, the meter will naturally not compensate for the temperature variance. In this case, accurate fluoride measurements are only possible if the temperature of the sample and the calibration solutions are close (no more than ±3°C apart). TEMPERATURE MEASUREMENT The temperature can be measured independently from fluoride concentration. · Immerse the temperature probe to a depth of at least 1 cm (½") in the prepared sample. The temperature of the solution will be shown on the lower part of the display. 7 · Immerse the fluoride and the reference electrode as well as the temperature probe to a depth of at least 1 cm (½") in the prepared buffer solution. Make sure that the electrodes are not touching the bottom of the beaker. Immerse the temperature probe close to the tip of the other electrodes. The display will show "CAL" and "BUF" together with an intermittent "~" symbol. The upper display will show the calibration point (100 ppm) with the temperature of the solution shown on the lower LCD. · Immerse the fluoride and the reference electrode to a depth of at least 1 cm (½") in the second buffer solution. Make sure that the electrodes are not touching the bottom of the beaker. Immerse the temperature probe close to the tip of the other electrodes. · When the CON symbol appears, it means that the second calibration solution has also been recognized and the reading has stabilized. Press CFM to confirm. · When the CON symbol appears, it means that the calibration solution has been recognized and the reading has stabilized. Press CFM to confirm the first calibration point. · Calibration is now complete and the meter automatically returns to the normal operational mode. TEMPERATURE CALIBRATION (only for technical personnel) All the meters are factory calibrated for temperature. The temperature probes are interchangeable and no temperature calibration is needed when they are replaced. If, for any reason, the temperature measurements seem inaccurate, temperature recalibration may be carried out. [. . . ] When shipping any instrument, make sure it is properly packaged for complete protection. To validate your warranty, fill out and return the enclosed warranty card within 14 days from the date of purchase. HANNA LITERATURE Hanna publishes a wide range of catalogs and handbooks for an equally wide range of applications. The reference literature currently covers areas such as: · Water Treatment · Process · Swimming Pools · Agriculture · Food · Laboratory · Thermometry and many others. For these and other catalogs, handbooks and leaflets, contact your dealer or the Hanna Customer Service Center nearest to you. [. . . ]