User manual HANNA INSTRUMENTS HI 93720

[. . . ] Insert a sample before adding reagent and press ZERO. 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 cuvet for reference (zero) and measurement. A flashing value higher than the maximum concentration readable (see specifications) indicates that the sample absorbs too much light, meaning that the concentration is too high. [. . . ] Reproduction in whole or in part is prohibited without the written consent of the copyright owner, Hanna Instruments Inc. , Woonsocket, Rhode Island, 02895 , USA. Hanna Instruments reserves the right to modify the design, construction and appearance of its products without advance notice. The HI 93720 meter measures the calcium hardness content, as CaCO3, in water and wastewater in the 0. 00 to 2. 70 mg/L (ppm) range. The meter uses an exclusive positive-locking system to ensure that the cuvet is in the same place every time it is placed into the measurement cell. The reagents are in liquid form and are supplied in bottles. The amount of reagent is precisely dosed to ensure maximum repeatability. Display codes aid the user in routine operations. The meters have an auto-shut off feature that will turn the instrument off after 10 minutes of non-use. Light Emitting Diode @ 555 nm Adaptation of the Standard Methods for the Examination of Water and Wastewater, 18th edition, calmagite method. The reaction between Ca and reagents causes a red tint in the sample Light Detector Silicon Photocell Environment 0 to 50°C (32 to 122°F); max 95% RH non-condensing Battery Type/Life 1 x 9 volt/40 hours Auto-Shut off After 10' of non-use Dimensions 180 x 83 x 46 mm (7. 1 x 3. 3 x 1. 8") Weight 290 g (10 oz. ). REQUIRED REAGENTS Code HI 93720A-0 HI 93720B-0 HI 93720C-0 Description Ca indicator Alkali solution EGTA solution Quantity 0. 5 mL 0. 5 mL 1 drop V REAGENT SETS HI 93720-01 Reagents for 100 tests HI 93720-03 Reagents for 300 tests OPERATIONAL GUIDE MEASUREMENT PROCEDURE · Turn the meter on by pressing ON/OFF. · When the LCD displays "- - -", it is ready. · Fill a graduated beaker to the 50 mL mark with the sample. · Add 0. 5 mL of HI 93720A Calcium indicator solution, then swirl to mix. · Add 0. 5 mL of HI 93720B Alkali solution for Calcium, then swirl to mix. B ON OFF · Remove the buffered blank and insert the second cuvet into the instrument, making sure that the notch on the cap is positioned securely into the groove. "SIP" will appear during measurement. READ TIMED INTERFERENCES Interference may be caused by excessive amounts of heavy metals. ACCESSORIES REAGENT SETS HI 93720-01 Reagents for 100 tests HI 93720-03 Reagents for 300 tests TIPS FOR AN ACCURATE MEASUREMENT The instruction listed below should be carefully followed during testing to ensure best accuracy. · Do not touch the cuvet walls with hands. · In order to maintain the same conditions during the zeroing and the measuring phases, it is necessary to close the cuvet to prevent any contamination. · Do not let the test sample stand too long after reagent is added or accuracy will be lost. · Whenever the cuvet is placed into the measurement cell, it must be completely free of fingerprints, oil or dirt. Wipe it thoroughly with HI 731318 or a lint-free cloth prior to insertion. · It is important that the sample does not contain any debris. · It is possible to take multiple readings in a row, but it is recommended that a zero reading be taken for each sample and that the same cuvet is used for zeroing and measurement. · It is important to discard the sample immediately after the reading is taken because the glass might become permanently stained. · Shaking the cuvet can generate bubbles in the sample, causing higher readings. [. . . ] Now, follow normal measurement procedure. The true value of the sample is the reading obtained multiplied by a factor of one hundred (the dilution factor). For your reference, factors to convert readings in mg/L to French degrees (FD), German degrees (DD) and English degrees (ED) of hardness are as follows: 1 mg/L = 0. 1 FD = 0. 056 DD = 0. 07 ED. CE DECLARATION OF CONFORMITY BATTERY REPLACEMENT Battery replacement must only take place in a non-hazardous area using a 9V alkaline battery. Simply slide off the battery cover on the back of the meter. [. . . ]