User manual HANNA INSTRUMENTS HI 98240

[. . . ] Instruction Manual HI 98230 · HI 98240 Printing and Logging pH Meters with GLP and Smart Electrodes www. hannainst. com Dear Customer, Thank you for choosing a Hanna Instruments Product. Please read this instruction manual carefully before using the instrument. This manual will provide you with all the necessary information for the correct use of the instruments. If you need additional technical information, do not hesitate to e-mail us at tech@hannainst. com. [. . . ] Note: A dashed line indicates that the calibration has never been performed. 18 19 mV CALIBRATION PROCEDURE (HI 98240 ONLY) A 4 point calibration must be performed. The first two calibration points are 0 and 350 mV for low range calibration; the other two points are 0 and 350 or 1900 mV for high range calibration. Connect a mV simulator (HI 8427 or HI 931001 with the proper connection cable) to the meter and set it to 0 mV. Press ALT and CAL when LCD is displaying mV. 3. User is prompted to enter password if it has been set to a value different from 0000, otherwise skip to step 6. Press ALT and CFM to confirm the password or ALT and CAL to return to normal operational mode. If password is correct or not set, the meter will display "0. 0 mV" on the upper LCD and "b1" on the lower; if wrong, it will return to normal operational mode without any message. When the "S" symbol blinks in the lower LCD, the reading is stable and calibration can be confirmed. Press ALT and CFM to confirm the first value. 13. When the "S" symbol blinks in the lower LCD, the reading is stable. Press ALT and CFM to confirm the third value. The meter will display "350 mV" in the upper LCD and "b4" on the lower one. Pressing the " " key, 1900 mV will be selected as calibration point. Note: +1900 mV is suggested as the last calibration point to obtain the best accuracy throughout the entire mV range. When the "S" symbol blinks in the lower LCD, the reading is stable. Press ALT and CFM to confirm the fourth value. Calibration is now complete and the instrument returns to normal operational mode. Note: "Err" message notifies the user if the selected value is wrong. TEMPERATURE CALIBRATION PROCEDURE (for technical personnel only) The meter is factory calibrated for temperature. It is recommended that the following procedure is performed by authorized technical personnel only. A two point calibration at 0. 0, 25. 0°C (32. 0, 77. 0°F) or 0. 0, 50. 0°C (32. 0, 122. 0°F) has to be performed in order to store the new calibration data in memory. Immerse the electrode with the built-in temperature sensor in the 0°C (32°F) temperature bath. Press RANGE until temperature reading is selected. [. . . ] Operation of this instrument in residential area could cause unacceptable interferences to radio and TV equipments, requiring the operator to take all necessary steps to correct interferences. The glass bulb at the end of the electrode is sensitive to electrostatic discharges. Avoid touching this glass bulb at all time. During calibration of instruments, ESD wrist straps should be worn to avoid possible damage to the electrode by electrostatic discharge. [. . . ]