User manual HANNA INSTRUMENTS HI 84432

[. . . ] Instruction Manual TITRATABLE ACIDITY MINITITRATOR & pH METER for Fruit Juices HI 84432 w w w. c o m 1 Dear Customer, Thank you for choosing a Hanna product. This manual will provide you with the necessary information for the correct use of the instrument. Please read it carefully before using the meter. [. . . ] · Press HELP to view the contextual help. · Press Continue or ESC to skip the message and enter titrator main screen. 24 · Press Purge to begin a purge cycle. The purging stops automatically after 5 minutes. To stop purging at any time and return to the main screen press ESC or Stop. During a purge, a countdown timer displays remaining time in 5 minute purge. Press Pause to interrupt the purge process. Press Pause or Stop (by pressing the corresponding function key in the purge screen) · after the first drops of fresh titrant appear at the dosing tip · in case an error condition is observed (empty titrant bottle, tubes or dosing tip disconected, pump error) · if you want to resume at a later time If Pause is pressed the next screen is displayed: Press Resume to continue purging. After the 5 minutes purging interval has elapsed the "Completed" message is displayed. Another purge period can be initiated by pressing Restart or press ESC to return to main titrator screen. 25 PUMP CALIBRATION PROCEDURE Please set up the instrument before performing the pump calibration. The calibration of the pump must be performed each time the pump tube, the reagent bottle or the pH electrode is changed. It is recommended to daily perform the pump calibration before you start titrations. Verify: The electrode has been calibrated in 8. 20 pH buffer. · Sample preparation: Precisely measure 2 mL of HI 84432-55 Pump Calibration Solution and add it to a clean beaker. Fill the beaker up to the 50 mL mark with the distilled or deionized water. · Place the stir bar into the beaker and then place the beaker in the appropriate place on the instrument top. · Place the electrode holder on the top of the beaker and secure it by turning clockwise. · Before immersing the pH electrode and temperature probe carefully rinse with deionized water. · Insert the calibrated pH electrode and the temperature probe through the electrode holder and immerse pH electrode bulb approximatively 2 cm (0. 8") into the standard paying attention not to touch the stir bar. · Insert the dosing tip in the appropriate holder place through guide tube. Note: The chemical reagents may be hazardous if improperly handled. Read Health and Safety Data Sheets before performing the test. · From the titrator main screen press CAL. The instrument displays the date and time of the last electrode calibration, and the date and time of the last pump calibration, or calibration expired messages. The next screen will be displayed. · Press Start. [. . . ] Concentra tion ou t of ra ng e. One of the keys is stu ck. Interna l error. 40 ELECTRODE CONDITIONING AND MAINTENANCE STORAGE PROCEDURE To assure a quick response time, the glass bulb should be kept moist and not allowed to dry out. Replace the solution in the protective cap with a few drops of HI 70300 or HI 80300 Storage Solution. Follow the Preparation Procedure section before taking measurements. Note: NEVER STORE THE pH ELECTRODE IN DISTILLED OR DEIONIZED WATER. PERIODIC MAINTENANCE Inspect the electrodes and the cables. [. . . ]