User manual HANNA INSTRUMENTS HI755

[. . . ] Please check the preparation of the zero cuvette. Light Low: There is not enough light to perform a measurement. Please check the preparation of the zero cuvette. No Light: The instrument cannot adjust the light level. [. . . ] 6· After a few seconds the display will show "-0. 0-". The meter is now zeroed and ready for measurement. 8· Add the content of one packet of HI 93749-0 reagent. 9· Replace the cap and shake vigurously. 10·Replace the cuvette into the holder and ensure that the notch on the cap is positioned securely into the groove. 11·Press and hold READ/ /TIMER for three seconds. The display will show the countdown prior to measurement. The beeper is playing a beep at the end of countdown period. Alternatively, wait for 6 minutes and just press READ/ /TIMER. In both cases, the lamp, cuvette and detector icons will appear on the display, depending on the measurement phase. 12·The instrument directly displays concentration in µg/L of chromium VI on the Liquid Crystal Display. INTERFERENCES: Interference may be caused by: · Vanadium above 1 mg/L, however, 10 seconds after the reaction the interference is removed. For accurate validation and calibration results, please perform tests at room temperature (18 to 25°C; 64. 5 to 77. 0°F). Use the Hanna CAL CHECKTM cuvettes (see "Accessories") to validate or calibrate instruments. VALIDATION 1· Turn the meter on by pressing ON/OFF. 2· When the beeper sounds briefly and the LCD displays dashes, the meter is ready. 3· Place the CAL CHECKTM Standard HI755-11 Cuvette A into the holder and ensure that the notch on the cap is positioned securely into the groove. 4· Press ZERO/CFM and the lamp, cuvette and detector icons will appear on the display, depending on the measurement phase. 5· After a few seconds the display will show "-0. 0-". The meter is now zeroed and ready for validation. 7· Place the CAL CHECKTM Standard HI755-11 Cuvette B into the holder and ensure that the notch on the cap is positioned securely into the groove. 8· Press CAL CHECK key and the lamp, cuvette and detector icons together with "CAL CHECK" will appear on the display, depending on the measurement phase. 9· At the end of the measurement the display will show the validation standard value. [. . . ] 3· Press ZERO/CFM to restore the factory calibration or press GLP/ again to abort factory calibration restore. 4· The instrument briefly indicates "donE" upon restoration of factory calibration prior to returning to measurement mode. 3-4 Warranty HI755 is warranted for two years against defects in workmanship and materials when used for its intended purpose and maintained according to the instructions. This warranty is limited to repair or replacement free of charge. [. . . ]