User manual HANNA INSTRUMENTS HI 84429

[. . . ] Instruction Manual TITRATABLE ACIDITY MINITITRATOR & pH METER for Dairy Products HI 84429 w w w. This manual will provide you with the necessary information for the correct use of the instrument. If you need additional technical information, do not hesitate to e-mail us at tech@hannainst. com. TABLE OF CONTENTS PRELIMINARY EXAMINATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 GENERAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] · When the reading is stable and close to the selected buffer, the (unstable measurement) symbol will disappear and the CFM key will become active. The instrument stores the calibration value and returns to pH meter/titrator calibration menu, where the date and time for the last pH will be updated. Notes: · A buffer confirmed during the calibration process is removed from the list of calibration buffers available for further calibration points. · If the value measured by the instrument is not close to the selected buffer a "Wrong Buffer" error message will be shown on the display. Check if the correct buffer has been used or regenerate the pH electrodes by following the Cleaning Procedure (see page 41). If necessary change the buffer or the electrode or pop the reference junction. · If the measured offset isn't within the preset limits (±45mV) the meter will display the message "Buffer Contaminated" alternatively with "Electrode Dirty/Broken". 21 · If the computed slope isn't within the preset limits the meter will display the message will be displayed. too low the symbol · If the "Wrong Old Slope" error message is displayed, an inconsistency exists between the current and the previous (old) calibration. Clear the calibration parameters by pressing Clear and proceed with calibration from the current calibration point. The instrument will keep all the confirmed values during the current calibration point. · If the temperature reading is out of the defined temperature range of the buffer (0÷45 °C) the "Wrong Buffer Temperature" error message will be displayed, and the symbol °C will blink on the dsplay. Calibration cannot be confirmed in this situation. 22 Notes: · To clear a previous calibration and to return to the default value, press Clear at any time after entering calibration mode. The "Calibration cleared" message will be shown for a few seconds on the display. If Clear is invoked during the first calibration point the instrument returns to the measurement mode. · The Clear key is displayed only if a previous calibration exists. pH BUFFER TEMPERATURE DEPENDENCE The temperature has an effect on pH. The calibration buffer solutions are affected by temperature changes to a lesser degree than normal solutions. During calibration the instrument will automatically calibrate to the pH value corresponding to the measured or set temperature. TEMP ºC 0 5 10 15 20 25 30 35 40 ºF 32 41 50 59 68 77 86 95 104 4. 30 8. 48 8. 44 8. 41 8. 37 8. 33 8. 30 8. 27 8. 24 8. 21 During calibration the instrument will display the pH buffer value at 25 ºC. 23 PUMP TUBE INSTALLATION To mount the new peristaltic pump tube follow next steps: · Position one peristaltic pump fixing ring on its location. Note: Purge the peristaltic pump until drops of reagent appears on the dosing tip by pressing the Purge key from the titrator main screen. To remove the tube of the peristaltic pump follow next steps: Caution: Purge line with water to remove NaOH from tube. · Detach the old tube system from the reagent bottle and from the dosing tip. · Pull the tube until the fixing rings are taken out from their location. · Remove the other side of the tube. PURGE Purging should be performed whenever the tube of the peristaltic pump is replaced or before starting a pump calibration or a titration. In order to start purging press the Purge key from the titrator main screen. [. . . ] Note:NEVER STORE THE pH ELECTRODE IN DISTILLED OR DEIONIZED WATER. PERIODIC MAINTENANCE Inspect the electrodes and the cables. The cable used for connection to the instrument must be intact and there must be no points of broken insulation on the cable or cracks on the electrode stem or bulb. Rinse off any salt deposits with water. pH CLEANING PROCEDURE · General · Milk deposits · Protein Soak in Hanna HI 7061 or HI 8061 General Cleaning Solution for approximately ½ hour. Soak in Hanna HI 700640 Cleaning Solution for milk deposits for approximately ½ hour (pH half cell only). [. . . ]