User manual HANNA INSTRUMENTS HI 96769C

[. . . ] Instruction Manual HI 96769C Anionic Surfactants ISM www. hannainst. com This Instrument is in Compliance with the CE Directives 1 2 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. [. . . ] · 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. 13 MEASUREMENT PROCEDURE · 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. · Fill the graduated glass vial with 25 mL of sample. For most accurate results, use of a class A laboratory pipette is strongly recommended. Alternatively, it is possible to use the plastic pipette, to fill the glass vial up to the 25 mL mark. · Add 2 drops of HI 95769A-0 Anionic Surfactants Reagent A and 2 drops of HI 95769B-0 Anionic Surfactants Reagent B. · Close the glass vial with its cap and invert to mix. The solution will turn blue. · Add exactly 10 mL of Chloroform reagent. For most accurate results, use a class A glass laboratory pipette is strongly recommended. Alternatively, it is possible to use another clean plastic pipette to fill the vial up to the 10 mL mark. 14 Notes: Chloroform is heavier than water thus it will sink to the bottom of the graduated glass vial; Do not mix up the pipettes. · Close tightly the glass vial with its cap and shake it vigorously for 30 seconds. Note: Block the cap with a finger during shaking. · Press and hold READ/ /TIMER for three seconds and the display will show the countdown. The beeper is playing a beep at the end of countdown period. Alternatively, wait for 2 minutes leaving the vial capped and undisturbed During this period, the chloroform layer separates from the aqueous layer: the color of the aqueous layer will fade slightly if anionic surfactants are present, while the chloroform layer will turn blue. · Using the long plastic pipette, remove the upper aqueous layer and discard. Do not remove the lower chloroform layer. · Add to the vial about 15 mL of deionized water, up to the 25 mL mark. [. . . ] 23 BATTERY MANAGEMENT To save battery, the instrument shuts down after 10 minutes of non-use in measurement mode and after 1 hour of non-use in calibration mode. 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. [. . . ]