User manual HANNA INSTRUMENTS HI 223

[. . . ] 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 the necessary information for correct use of the instrument, as well as a precise idea of its versatility. If you need additional technical information, do not hesitate to e-mail us at tech@hannainst. [. . . ] Press the ARROW keys to scroll between same parameter for different records, while pH, mV, temperature, Hour, Year, oFFS, SLoP or dEL record is displayed: Or to scroll between different dates while dAtE or dEL date is displayed. Press the RANGE key and the instrument will display the next logged parameter, as follows: The mV value on the primary LCD and the record number on the secondary LCD. Note: Before displaying the Hour, Year, oFFS or SLoP messages, the record number is displayed for about one second. The RANGE key has no effect if nuLL record message is displayed on the first LCD line. You can skip this message by selecting an undeleted record (date) using the ARROW keys. Press SET key to select the current record, the records from the selected date or all records to be deleted. Press the ARROW keys to change the record or the date. Press the CFM key to confirm the deleting of the selected record, all the records for the selected date, or all the records and the instrument will display on the secondary LCD the nuLL message. Note: Pressing RANGE key the instrument skips to the pH information on the next undeleted record. The instrument optimizes the usage of the memory when it returns to measurement mode after a deleting operation is performed. This will change the record numbers of logged data. if all the records are deleted the instrument returns to the measuring mode. After the LOG key is pressed or dEL is confirmed the instrument will display the amount of free log space for about one second (example: 25 records free). Setup mode allows viewing and modification of the following parameters: Calibration Alarm Time Out Instrument ID Current Time (hour & minute) Current Date (month & day) Current Year pH Resolution (HI 223 only) Beep Status Baud Rate (serial communication) Command Prefix (serial communication) To enter the Setup mode press the SET/CLR key while the instrument is in measuring mode. Press the RANGE key to toggle between the displayed parameters. press the ARROWkeys to increase or decrease the displayed value. Press the CFM key to save the modified value or the CAL key to cancel. press the ARROW keys to select the next/previous parameter. CALIBRATION ALARM TIME OUT CHANGE Press the CAL key when the calibration time out is displayed. Press the CFM key to save the modified calibration time out value or press the CAL key to cancel without saving the calibration time out. Press the CFM key to save the modified instrument ID value or press the CAL key to cancel without saving the instrument ID. Press the CFM key to save the modified value or press the CAL key to cancel without saving the time. [. . . ] The lower the temperature, the higher the resistance. It takes more time for the reading to stabilize if the resistance is higher. In addition, the response time will suffer to a greater degree at temperatures below 25 °C. Since the resistance of the pH electrode is in the range of 50-200 Mohm depending on the composition of the glass, the current across the membrane is in the pico Ampere range. [. . . ]