User manual HANNA INSTRUMENTS HI 991404

[. . . ] To avoid electrical shock, do not use this instrument when voltages at the measurement surface exceed 24 VAC or 60 VDC. To avoid damages or burns, do not perform any measurement in microwave ovens. ISTR991404R1 05/02 PRELIMINARY EXAMINATION Remove the instrument from the packing material and examine it carefully. If any damage has occurred during shipment, immediately notify your Dealer or the nearest Hanna Customer Service Center. The meters are supplied with: · pH 4. 01 and 7. 01 buffer solutions (20 mL each); · HI 70031 1413 µS/cm calibration solution, for HI 991404; · HI 70030 12. 88 mS/cm calibration solution, for HI 991405; · HI 1293D pH-electrode with differential input signal; · Hanna 12 VDC power adapter; · Instruction manual. [. . . ] Reproduction in whole or in part is prohibited without the written consent of the copyright owner, Hanna Instruments Inc. , Woonsocket, Rhode Island, 02895 , USA. Hanna Instruments reserves the right to modify the design, construction and appearance of its products without advance notice. Liquid Crystal Display ON/OFF/MODE button Power supply connector 12 VDC power adapter HI 1293D pH-electrode with differential input, pipe thread 1/2'' NPT 6. EC/TDS/Temperature probe, pipe thread 1/2'' NPT (works also as matching pin for pH-electrode) 7. SET/HOLD button OPERATIONAL GUIDE To turn the meter on Connect the pH electrode to the meter. Connect the 12VDC adapter to the meter and to the mains; the display will lit. To change the temperature unit To change the temperature unit (from °C to °F), from measurement mode, press and hold the MODE button until TEMP and the current temperature unit are displayed on the lower LCD. Use the SET/HOLD button to change the temperature unit, and then press MODE button twice to return to normal measurement mode. To freeze the display Press and hold the SET/HOLD button for 2-3 seconds until HOLD appears on the secondary display. Taking measurements Select the pH, EC or TDS mode with the SET/HOLD button. In order to ensure better accuracy, probes should not touch or stand close to the walls or bottom of the sample vessel. The pH, EC or TDS value automatically compensated for temperature is shown on the primary LCD while the secondary LCD shows the temperature of the sample. The measurements should be taken when the stability symbol on the top left of the LCD disappears. Note: Measurements have to be taken with both probes (pHelectrode and EC/TDS/temperature probe) immersed in the same vessel. To change the EC/TDS conversion factor (CONV) and the temperature compensation coefficient (BETA) · From measurement mode, press and hold the MODE button until TEMP and the current temperature unit are displayed on the lower LCD. · Press the MODE button again to show the current conversion factor. · Press the MODE button to show the current temperature compensation coefficient . · Press the SET/HOLD button to change the temperature compensation coefficient . To turn the meter off Press the MODE button while in normal measurement mode. Notes: · Before taking any measurement make sure the meter has been calibrated. · To clear a previous calibration, press the MODE button after entering the calibration mode. The lower LCD will display ESC for 1 second and the meter will return to normal measurement mode. · If measurements are taken in different samples successively, rinse the probes thoroughly to eliminate cross-contamination; and after cleaning, rinse the probes with some of the sample to be measured. pH calibration procedure From pH measurement mode, press and hold the MODE button until CAL is displayed on the lower LCD. [. . . ] EC calibration procedure · From EC measurement mode, press and hold the MODE button until CAL is displayed on the lower LCD. · Release the button and immerse the probe in the proper calibration solution: HI 70031 (1413 µS/cm) for HI 991404 and HI 70030 (12. 88 mS/cm) for HI 991405. · Once the calibration has been automatically performed, the LCD will display OK for 1 second and the meter will return to normal measurement mode. · Since there is a known relationship between EC and TDS readings, it is not necessary to calibrate the meter in TDS Note: for storing calibration data in the non-volatile memory, turn the meter OFF and then ON again through the MODE button. The CAL symbol on the LCD means that the meter is calibrated. pH ELECTRODE MAINTENANCE · When not in use, rinse the electrode with water to minimize contamination and store it with a few drops of storage (HI 70300) or pH 7 (HI 7007) solution in the protective cap after use. [. . . ]