User manual HANNA INSTRUMENTS HI 2400

[. . . ] HANNA LITERATURE Hanna publishes a wide range of catalogs and handbooks for an equally wide range of applications. The reference literature currently covers areas such as: · · · · · · Water Treatment Process Agriculture Food Laboratory Thermometry Instruction Manual HI 2400 Microprocessor Dissolved Oxygen Bench Meter and many others. New reference material is constantly being added to the library. For these and others catalogs, handbooks and leaflets, contact your dealer or the Hanna Customer Service Center nearest to you. [. . . ] You can use a clean lint-free cardboard or cloth. Rub the cathode very gently side to side 4-5 times. This will be enough to polish and remove any stains without damaging the platinum tip. Afterwards, rinse the probe with deionized or distilled water and install a new membrane cap using fresh electrolyte and follow the steps above. Important In order to have accurate and stable measurements, it is important that the surface of the membrane is in perfect condition. This semipermeable membrane isolates the sensor elements from the environment but allows oxygen to enter. If any dirt is observed on the membrane, rinse carefully with distilled or deionized water. If any imperfections still exist, or any damage is evident (such as wrinkles or tears-holes), the membrane should be replaced. Make sure that the O-Ring sits properly in the membrane cap. This also indicates the possibility of a broken probe cable. PROBE POLARIZATION The probe is under polarization with a fixed voltage of approximately 800 mV. Probe polarization is essential for stable measurements with the same recurring degree of accuracy. With the probe properly polarized, oxygen is continually "consumed" when it passes through the sensitive diaphragm and dissolves in the electrolyte solution contained in the probe. If polarization is interrupted, the electrolyte solution continues to be enriched with oxygen until it reaches an equilibrium with the surrounding solution. Whenever measurements are taken with a non-polarized probe, the oxygen level revealed is both that of the tested solution as well as that present in the electrolyte solution. The calibration of this instrument is very simple. Before proceeding with the calibration, make sure the probe is ready for measurements (see page 9), i. e. the membrane cap is filled with electrolyte and the probe is connected to the meter and properly polarized. For an accurate calibration, it is recommended to wait at least 15 minutes to ensure precise conditioning of the probe. Keep the protective cap on during the polarization time and remove it for the calibration and the measurements. Follow the calibration procedure on page 12. 10 31 PROBE & MEMBRANE MAINTENANCE D. O. MEASUREMENTS (in ppm or %) Make sure the meter has been calibrated (see page 12) and the protective cap has been removed. Salinity and Altitude compensation If the sample contains significant concentration of salinity or if you are performing measurements at an altitude different from sea level, the readout values must be corrected, taking into account the lower degree of oxygen solubility in these situations as explained on pages 18-20. [. . . ] · The temperature calibration procedure is now completed. Press the CAL key to enter the change setting mode, the command prefix will start blinking. Select a different command prefix (between 0 to 47 decimal) by pressing the UP or DOWN arrow keys. SETUP Setup is used to view or change the instrument parameters. To enter in View Settings press the SETUP key when the meter is in measurement mode. View Setttings By pressing the UP or DOWN arrow keys you can view the setting values for the following parameters: Press the CFM key to confirm the command prefix setting. Note: The Command Prefix does not have to be changed using HI 92000 Hanna software. 24 17 · Salinity Compensation · Altitude Compensation · Log Interval · Time · Date · Baud Rate · Command Prefix · Buzzer Status If you press the SETUP key anytime in theView Settings Mode the device will enter the measurement mode. [. . . ]