User manual HANNA INSTRUMENTS HI 95721

[. . . ] Instruction Manual HI 95721C Iron High Range ISM MAN95721R2 07/06 w w w . h a n n a i n s t . c o m www. hannainst. com This Instrument is in Compliance with the CE Directives 20 1 Dear Customer, Thank you for choosing a Hanna product. This manual will provide you with the necessary information for the correct use of the instrument. Please read it carefully before using the meter. If you need additional technical information, do not hesitate to e-mail us at tech@hannainst. com. [. . . ] Although good precision suggests good accuracy, precise results can be inaccurate. In a laboratory using a standard solution of 1. 50 mg/L Iron and a representative lot of reagent, an operator obtained with a single instrument a standard deviation of 0. 01 mg/L. 5 · After a few seconds the display will show "-0. 0-". The meter is now zeroed and ready for calibration. · Place the CAL CHECKTM Standard HI 95721-11 Cuvet B into the holder and ensure that the notch on the cap is positioned securely into the groove. 16 PRINCIPLE OF OPERATION Absorption of light is a typical phenomenon of interaction between electromagnetic radiation and matter. When a light beam crosses a substance, some of the radiation may be absorbed by atoms, molecules or crystal lattices. If the value is found out of specifications, please check that the cuvets are free of fingerprints, oil or dirt and repeat validation. If results are still found out of specifications then recalibrate the instrument. 6 15 · Hold READ/TIMER for three seconds. The display will show the countdown prior to measurement. Alternatively, wait for 3 minutes and just press READ/TIMER. In both cases "SIP" will blink during measurement. or · The instrument directly displays concentration in mg/L of iron on the Liquid Crystal Display. INTERFERENCES · Alkalinity: above 2, 000 mg/L (as CaCO3). May slow down color development (negative error). To resolve this, neutralize the sample with diluted HCl. does not interfere: reagent contains a masking agent. 2+ A microprocessor controlled special tungsten lamp emits radiation which is first optically conditioned and beamed to the sample contained in the cuvet. The optical path is fixed by the diameter of the cuvet. Then the light is spectrally filtered to a narrow spectral bandwidth, to obtain a light beam of intensity Io or I. The photoelectric cell collects the radiation I that is not absorbed by the sample and converts it into an electric current, producing a potential in the mV range. The microprocessor uses this potential to convert the incoming value into the desired measuring unit and to display it on the LCD. The measurement process is carried out in two phases: first the meter is zeroed and then the actual measurement is performed. The cuvet has a very important role because it is an optical element and thus requires particular attention. It is important that both the measurement and the calibration (zeroing) cuvets are optically identical to provide the same measurement conditions. Whenever possible use the same cuvet for both. [. . . ] Repeat the calibration procedure with the right standard solution, and verify it is not expired. If the calibration procedure fails again, contact your dealer or the nearest Hanna Customer Service Center. ERROR MESSAGES a) on zero reading This indicates that the zeroing procedure failed due to a low signal-tonoise ratio. "No Light": the instrument cannot adjust the light level. [. . . ]