User manual HANNA INSTRUMENTS HI 96725

[. . . ] Follow the instructions of the measurement procedure for zeroing the meter. Under range: A blinking "0. 00" indicates that the sample absorbs less light than the zero reference. Check the procedure and make sure you use the same cuvette for reference (zero) and measurement. Over Range: A flashing value of the maximum concentration indicates an over range condition. [. . . ] 9· After a few seconds the display will show "-0. 0-". The meter is now zeroed and ready for measurement. 10·Add one packet of the HI 93705C amino acid reagent and shake until it has dissolved. 11·Replace the cuvette into the holder and ensure that the notch on the cap is positioned securely into the groove. 12·Press and hold READ/ /TIMER for three seconds and the display will show the countdown prior to measurement or alternatively wait for 3 minute and press READ/ /TIMER. An audible "beep" indicates the end of countdown period. In all cases the lamp, cuvette and detector icons will appear on the display, depending on the measurement phase. 13·At the end of measurement, the instrument directly displays concentration in mg/L of silica (SiO2) on the LCD. INTERFERENCES: or Interference may be caused by: Phosphate above 60 mg/L (causes a 2% reduction in reading). Phosphate above 75 mg/L (causes an 11% reduction in reading). 13 Sulfide and high concentration of iron. Eliminate color and turbidity interferences by zeroing the meter with the original water sample. 9· At the end of the measurement the display will show the validation standard value. The reading should be within specifications as reported on the CAL CHECKTM Standard Certificate. If the value is found out of specifications, please check that the cuvettes are free of fingerprints, oil or dirt and repeat validation. If results are still found out of specifications then recalibrate the instrument. 9 11·Then the date of last calibration (e. g. : "01. 08. 2009") appears on the display, or "01. 01. 2009" if the factory calibration was selected before. In both cases the year number is blinking, ready for date input. 12·Press GLP/ to edit the desired year (2009-2099). If the key is kept pressed, the year number is automatically increased. 13·When the correct year has been set, press ZERO/CFM or READ/ /TIMER to confirm. Now the display will show the month blinking. 14·Press GLP/ to edit the desired month (01-12). If the key is kept pressed, the month number is automatically increased. 11-13 FACTORY CALIBRATION RESTORE It is possible to delete the calibration and restore factory calibration. 2 Factory Calibration Restore Accessories: REAGENT SETS HI 93705-01 Reagents for 100 tests HI 93705-03 Reagents for 300 tests OTHER ACCESSORIES HI 96705-11 CAL CHECKTM Standard Cuvettes (1 set) HI 721310 9V battery (10 pcs) HI 731318 Cloth for wiping cuvettes (4 pcs) HI 731331 Glass cuvettes (4 pcs) HI 731335 Caps for cuvettes (4 pcs) HI 93703-50 Cuvette cleaning solution (230 mL). CALIBRATION Note: It is possible to interrupt the calibration procedure at any time by pressing CAL CHECK or ON/OFF keys. [. . . ] · Turn the instrument upside down and remove the battery cover by turning it counterclockwise. 4· Place the CAL CHECKTM Standard 5-6 HI 96705-11 Cuvette A into the cuvette holder and ensure that the notch on the cap is positioned securely into the groove. 5· Press ZERO/CFM and the lamp, cuvette and detector icons will appear on the display, depending on the measurement phase. 6· After a few seconds the display will show "-0. 0-". The meter is now zeroed and ready for calibration. [. . . ]