User manual HANNA INSTRUMENTS HI 96720C

[. . . ] Instruction Manual HI 96720C Calcium Hardness ISM www. hannainst. com 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. PRELIMINARY EXAMINATION Please examine this product carefully. [. . . ] Follow the instructions of the measurement procedure for zeroing the meter. 9 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. Battery low: The battery must be replaced soon. 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. Dead battery: This indicates that the battery is dead and must be replaced. Once this indication is displayed, the meter will lock up. To obtain accurate measurements, remove such bubbles by swirling or by gently tapping the cuvette. · Do not let the reacted sample stand too long after reagent is added, or accuracy will be lost. · It is possible to take multiple readings in a row, but it is recommended to take a new zero reading for each sample and to use the same cuvette for zeroing and measurement. · 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. · 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. · Fill a graduated beaker with 50 mL of sample. · Add 0. 5 mL of HI 93720A-0 Calcium indicator solution, then swirl to mix. · In the same beaker add 0. 5 mL of HI 93720B-0 Alkali solution for Calcium, then swirl to mix. · Fill two cuvettes with 10 mL of sample each. STARTUP Prepare the instrument for measurement as follows: · Unpack the instrument by removing the dust protection sleeve from the instrument cuvette holder. · Place the battery in the instrument as described in the "BATTERY REPLACEMENT" chapter. · Place the instrument on a flat table. · Do not place the instrument under direct sun light. · Add 1 drop of HI 93720C-0 EGTA solution to one cuvette, replace the cap and swirl the solution. This is the blank. · Place the blank into the cuvette holder and ensure that the notch on the cap is positioned securely into the groove. MEASUREMENT PROCEDURE To compensate the meter for the sample turbidity or color, the measurement takes place in two phases. First, the meter is zeroed using the unreacted sample. [. . . ] The blinking "ZERO" means that a new zero has to be performed. One fresh battery lasts for around 750 measurements, depending on the light level. The remaining battery capacity is evaluated at the instrument startup and after each measurement. The instrument displays a battery indicator with three levels as follows: · 3 lines for 100 % capacity · 2 lines for 66 % capacity · 1 line for 33 % capacity · Battery icon blinking if the capacity is under 10 %. [. . . ]