User manual HANNA INSTRUMENTS HI 9143M

[. . . ] Dissolved oxygen is indicated in hundredths of parts per million (ppm=mg/L) or in % of saturation . The temperature range is indicated in centigrade from 0 to 50°C with 0. 1°C resolution. The ppm and the % saturation are both compensated for changes in solubility of oxygen in water and for permeability of the membrane as well as the temperature effect. Salinity compensation in water allows determination of mg/L of dissolved oxygen in 1 salty waters and the altitude compensation readjusts for the altitude variance (HI 9143 only). [. . . ] · "COND" appears on the ON/OFF display to inform you that the probe is in auto-conditioning (automatic polarization) mode. · Once "COND" disappears the probe is polarized and instrument can be calibrated. 6 · · For an accurate calibration, it is recommended to wait an additional 5 or 10 minutes to ensure optimum conditioning of the probe. "----" appears on the larger LCD together with "CAL" to indicate that the instrument is in calibration mode. The instrument will automatically standardize itself to the actual saturation value. 1 minute it will show "100%" on the LCD and a small "SAMPLE" to indicate that the calibration is complete. CAL CAL SAMPLE % °C · HI 9143 only: press FACTOR and ensure F1 and F2 are set to the appropriate altitude and salinity values (pages 10-11). Notes:· The instrument must be calibrated whenever the probe, membrane or the electrolyte is changed. · The display may be switched from readCAL ings in % saturation to mg/L without recalibration, by simply pressing RANGE. RANGE 7 MEASUREMENT Make sure the meter has been calibrated and the protective cap has been removed. Immerse the tip of the probe in the sample to be tested and ensure that the temperature sensor is also immersed. To display values in % saturation, press RANGE. RANGE For accurate dissolved oxygen measurements, a water movement of at least 30 cm (12")/sec is required. This is to ensure that oxygen depleted on the membrane surface is constantly replenished. During field measurements, this condition may be obtained by manually stirring the probe. During laboratory measurements, the use of a magnetic stirrer to ensure a certain agitation of the fluid is recommended. This way, any errors due to the presence of air bubbles on the menbrane surface are minimized. For an accurate measurement, allow sufficient time for thermal equilibrium between the probe and the measurement sample (a few minutes if the temperature difference is several degrees). mg/L READINGS The mg/L readings make it possible to read the concentration of the dissolved oxygen directly in ppm. 8 If the sample contains significant salinity or if the measurement is taken at a higher altitude than sea level, the readout values must be corrected (by taking into account the lower degree of oxygen solubility in such conditions - see below). With HI 9143, set the altitude and/or the salinity before calibration and taking mg/L measurements. With HI 9145, the readout is at sea level and for liquids without any salt content. % O2 SATURATION READINGS The % O2 reading provides the rate of oxygen saturation with reference to 100. 0% at sea level. TEMPERATURE READINGS The lower part of the display will show the measured temperature in Celsius degrees. SAMPLE % °C Allow the probe to reach thermal equilibrium with the sample before taking any measurement. The greater the difference between the ambient temperature and the temperature of the sample, the longer it will take the probe to acclimatized itself to the sample. 9 ALTITUDE COMPENSATION HI 9143 Press FACTOR and "F1" will be displayed. Use the UP and the DOWN keys to set the altitude from 0 and 1900 m, in steps of 100 m. (With HI 9143M the altitude can be set from 0. 0 to 4. 0 Km, in steps of 0. 1 Km). FACTOR SAMPLE ppm F1 or HI 9145 With HI 9145, all the D. O. 2 12 · · Make sure that the rubber O-ring is seated properly inside the membrane cap. [. . . ] Reproduction in whole or in part is prohibited without the written consent of the copyright owner. Hanna Instruments reserves the right to modify the design, construction and appearance of its products without advance notice. 16 CE DECLARATION OF CONFORMITY DECLARATION OF CONFORMITY We Hanna Instruments Srl V. le delle industrie 12 35010 Ronchi di Villafranca (PD) ITALY herewith certify that the waterproof dissolved oxygen meters HI 9143 IEC 801-2 IEC 801-3 IEC 801-4 EN 55022 Electrostatic Discharge RF Radiated Fast Transient Radiated, Class B HI 9145 have been tested and found to be in compliance with the following regulations: Date of Issue: 11-10-1995 D. Volpato - Engineering Manager On behalf of Hanna Instruments S. r. l. Recommendations for Users Before using these products, make sure that they are entirely suitable for the environment in which they are used. Operation of this instrument in residential area could cause unacceptable interference to radio and TV equipment, requiring the operator to take all necessary steps to correct interferences. Any variation introduced by the user to the supplied equipment may degrade the instrument's EMC performance. [. . . ]