Instruction Manual HI 96728C Nitrate ISM www.hannainst.
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. TABLE OF CONTENTS PRELIMINARY EXAMINATION ................................................................................................ 3 GENERAL DESCRIPTION .................................................
PRELIMINARY EXAMINATION Please examine this product carefully. Make sure that the instrument is not damaged. If any damage occurred during shipment, please notify your Dealer. Each HI 96728 Ion Selective Meter is supplied complete with: • Two Sample Cuvettes and Caps • CAL CHECK standard cuvettes • 9V Battery • Cloth for wiping cuvettes • Instrument quality certificate • Instruction Manual • Rigid carrying case Note: Save all packing material until you are sure that the instrument works correctly.
GENERAL DESCRIPTION The HI 96728 is an auto diagnostic portable microprocessor meter that benefits from Hanna’s years of experience as a manufacturer of analytical instruments. It has the advanced optical system based on a special Tungsten Lamp and a narrow band interference filter that allows most accurate and repeatable readings. All instruments are factory calibrated and the electronic and optical design minimizes the need of frequent calibration.
SPECIFICATIONS Range Resolution Accuracy Typical EMC Deviation Light Source Light Detector Method 0.0 to 30.0 mg/L 0.1 mg/L ±0.5 mg/L ±10% of reading@ 25°C ±0.1 mg/L Tungsten lamp Silicon Photocell with narrow band interference filter @ 525 nm Adaptation of the cadmium reduction method. The reaction between nitratenitrogen and the reagent causes an amber tint in the sample.
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.
A microprocessor controlled special tungsten lamp emits radiation which is first optically conditioned and beamed to the sample contained in the cuvette. The optical path is fixed by the diameter of the cuvette. 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.
KEYPAD DESCRIPTION • ON/OFF: to turn the meter on and off. • ZERO/CFM: this is a bi-functional key. Just press to zero the meter prior to measurement, or confirm edited values. In calibration mode press to confirm factory calibration restore. • READ/ /TIMER: this is a multi-functional key. In measurement mode, press to make a measurement, or press and hold for three seconds to start a pre-programmed countdown prior to measurement. In GLP mode press to view the next screen.
ERRORS AND WARNINGS The instrument shows clear messages when erroneous condition appears. Messages are also displayed when the obtained values are outside expected range. The beeper is playing a beep on errors. a) on zero reading Light High: There is too much light to perform a measurement. 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.
Over Range: A flashing value of the maximum concentration indicates an over range condition. The concentration of the sample is beyond the programmed range: dilute the sample and re-run the test. c) during calibration procedure Standard Low: The standard reading is less than expected. Standard High: The standard reading is higher than expected. d) other errors and warnings Cap error: Appears when external light enters in the analysis cell. Assure that the cuvette cap is present.
GENERAL TIPS FOR AN ACCURATE MEASUREMENT The instructions listed below should be carefully followed during testing to ensure best accuracy. • Color or suspended matter in large amounts may cause interference, therefore these should be removed by treatment with active carbon and by prior filtration. • For a correct filling of the cuvette: the liquid in the cuvette forms a concavity on the top; the bottom of this concavity must be at the same level of the 10 mL mark.
• After the reading it is important to discard immediately the sample, otherwise the glass might become permanently stained. • All the reaction times reported in this manual are referred to 20°C (68°F). As a general rule of thumb, they should be doubled at 10°C (50°F) and halved at 30°C (86°F). • In order to maximize accuracy, prior to a measurement follow the validation procedure to be sure that the instrument is properly calibrated. If necessary, calibrate the instrument.
• Place the cuvette into the cuvette holder and ensure that the notch on the cap is positioned securely into the groove. • Press ZERO/CFM and the lamp, cuvette and detector icons will appear on the display, depending on the measurement phase. • After a few seconds, the display will show “-0.0-”. The meter is now zeroed and ready for measurement. Remove the cuvette. • Add one packet of the HI 93728-0 reagent.
• Alternatively, wait for 3 minutes then just press READ/ /TIMER. In all cases, the lamp, cuvette and detector icons will appear on the display, depending on the measurement phase. • At the end of measurement, the instrument directly displays concentration in mg/L of nitrate-nitrogen on the LCD. • To convert the reading to mg/L of nitrate (NO3-), multiply by the factor 4.43. INTERFERENCES: Interference may be caused by: Ammonia and amines, as urea and primary aliphatic amines.
VALIDATION PROCEDURE Use the validation procedure to ensure that the instrument is properly calibrated. Warning: Do not validate the instrument with any standard solutions other than the HANNA CAL CHECKTM Standards, otherwise erroneous results will be obtained. • Turn the meter on by pressing ON/OFF. • When the beeper sounds briefly and the LCD displays dashes, the meter is ready. The blinking “ZERO” indicates that the instrument needs to be zeroed first.
• Press CAL CHECK and the lamp, cuvette and detector icons together with “CAL CHECK” will appear on the display, depending on the measurement phase. • At the end of the measurement the display will show the validation standard value. The reading should be within specifications as reported in the CAL CHECKTM Standard Certificate. If the value is found out of the specifications, please check that the cuvettes are free of fingerprints, oil or dirt and repeat validation.
CALIBRATION PROCEDURE Note: It is possible to interrupt calibration procedure at any time by pressing CAL CHECK or ON/OFF keys. Warning: Do not calibrate the instrument with standard solutions other than the HANNA CAL CHECKTM Standards, otherwise erroneous results will be obtained. • Turn the meter on by pressing ON/OFF. • When the beeper sounds briefly and the LCD displays dashes, the meter is ready. • Press and hold CAL CHECK for three seconds to enter calibration mode.
• After a few seconds the display will show “-0.0-”. The meter is now zeroed and ready for calibration. The blinking “READ” asks for reading calibration standard. • Remove the cuvette. • Place the CAL CHECK TM Standard HI 96728-11 Cuvette B into the cuvette holder and ensure that the notch on the cap is positioned securely into the groove. • Press READ/ /TIMER and the lamp, cuvette and detector icons will appear on the display, depending on the measurement phase.
DATE INPUT • Press GLP/ to edit the desired year (2009-2099). If the key is kept pressed, the year number is automatically increased. or • When the correct year has been set, press ZERO/CFM or READ/ /TIMER to confirm. Now the display will show the month blinking. • Press GLP/ to edit the desired month (01-12). If the key is kept pressed, the month number is automatically increased. or • When the correct month has been set, press ZERO/CFM or READ/ /TIMER to confirm.
• The instrument will return automatically to measurement mode by displaying dashes on the LCD. GLP In GLP mode, the last calibration date can be verified and the factory calibration can be restored. LAST CALIBRATION DATE To display the calibration date: • Press GLP/ to enter GLP mode. The calibration month and day will appear on the main display and the year on the secondary display. • If no calibration was performed, the factory calibration message, “F.
• Press READ/ /TIMER to enter in the factory calibration restore screen. The instrument asks for confirmation of user calibration delete. • Press ZERO/CFM to restore the factory calibration or press GLP/ again to abort factory calibration restore. • The instrument briefly indicates “donE” upon restoration of factory calibration prior to returning to measurement mode.
BATTERY REPLACEMENT To replace the instrument’s battery, follow the steps: • Turn the instrument off by pressing ON/OFF. • Turn the instrument upside down and remove the battery cover by turning it counterclockwise. • Extract the battery from its location and replace it with a fresh one. • Insert back the battery cover and turn it clockwise to close.
WARRANTY HI 96728 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. Damages due to accident, misuse, tampering or lack of prescribed maintenance are not covered. If service is required, contact your dealer. If under warranty, report the model number, date of purchase, serial number and the nature of the failure.
Hanna Instruments Inc. Highland Industrial Park 584 Park East Drive Woonsocket, RI 02895 USA Technical Support for Customers Tel. (800) 426 6287 Fax (401) 765 7575 E-mail tech@hannainst.com www.hannainst.
