User manual HANNA INSTRUMENTS HI 96711C

[. . . ] Instruction Manual HI 96711C Free and Total Chlorine 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. TABLE OF CONTENTS PRELIMINARY EXAMINATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] · 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. 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. RANGE SELECTION The HI 96711 can measure Free chlorine when range P1 is selected or Total chlorine when range P2 is selected. To change the active range follow the procedure: · Turn the meter on by pressing ON/OFF. · After startup, the range identification number is displayed on the secondary LCD as P1 or P2. Code P1 P2 Parameter Free Chlorine Total Chlorine · Press RANGE/GLP/ to change the range. The range can be changed any time when the instrument is in measurement mode. The selected range is memorized and the selection remaines unchanged at power off or when the battery is removed. 14 15 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. After the reagents are added the reacted sample is measured. Important note: Free and Total Chlorine have to be measured separately with fresh unreacted samples if both values are requested. · Turn the meter on by pressing ON/OFF. The display briefly shows all tags on. · After a few seconds, the display will show "-0. 0-". The meter is now zeroed and ready for measurement. · Add the content of one packet of the specific test reagent, for: Free Chlorine: 1 packet of HI 93701-0 or Total Chlorine: 1 packet of HI 93711-0 · 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. · Replace the cap and shake gently for 20 seconds (or 2 minutes in case of seawater analysis). · Pay attention to the selected range. [. . . ] If a valid measurement was displayed before auto shut off, the value is displayed when the instrument is switched on. 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. [. . . ]