User manual EUTECH INSTRUMENTS DO 700

[. . . ] Instruction Manual DO 700 Dissolved Oxygen/ºC/ºF Bench Meter Technology Made Easy . . . Part of Thermo Fisher Scientific 68X541703 Rev. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GETTING STARTED. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2. 1 2. 2 2. 3 Keypad Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] The concentration value based on the factory default calibration is shown. or to adjust the reading to match the known Press oxygen concentration value. 4) 5) 8 Press to confirm the calibration. The primary display will blink briefly before returning to measurement mode. In addition, the calibration is limited to ±40% adjustment of the factory default value to prevent erroneous calibrations. 6) 5. SETUP FUNCTIONS Use the setup feature to customize your instrument operation. There are two setup menus; one menu is derived from the % saturation mode and the other from the mg/L (or ppm) concentration mode. First, select the appropriate measurement mode you wish to adjust by pressing until the desired units are displayed. During for 5 seconds to enter SETUP measurement, press and hold mode of the parameter being measured. Press Press Press or to change programs or change options. to select the program or confirm selection. to go back one level or return to measurement mode. 5. 1 1. 0 CAL (Calibration) Press to view stored calibration points. Note: % saturation mode will list two points, while concentration mode has only one point. 9 5. 2 2. 0 ELE (Electrode Information) Press to view calibration factor (CAL. F) TIP: The factor is an indication of the probe's efficiency. or to select "Yes" (Erase memory) or "No". to confirm. 12 6. TAKING MEASUREMENTS During measurement the dissolved oxygen reading is automatically compensated for pressure and salinity. For best accuracy, ensure the pressure and salinity settings are adjusted accordingly from the setup menu. The factory default value for barometric pressure is 760 mm Hg or 101. 3 bar (sea level). Press · · · · to select the desired measurement mode: Percentage Saturation (%) and Temp (º C or ºF) Concentration (mg/L or ppm) and Temp (º C or ºF) Follow these general rules when taking measurements: Keep the membrane free from contact with solid objects. Provide stirring of your solutionthis helps to overcome oxygen consumption of the probe and prevents air bubble entrapment. The pre-assembled cap must be completely submersed to obtain an accurate reading in solutions. Rinse the probe well with DI water or rinse solution between measurements. · · · · 13 6. 1 HOLD Function For prolonged observation of a reading, press during measurement mode to freeze the display. To release the held value and resume measurement, press memory by pressing . again or insert the held value into 6. 2 Storing and Recalling Data The DO 700 can retain up to 100 data points into memory for later retrieval. to insert the measured value 1) In the measurement mode, press into memory. The location of the most or to select the recent stored data is displayed first. Press location of the desired data, then press to accept. 3) Press to return to the stored data location. [. . . ] When DO level is too high, this indicates too much power is used than necessary for aeration resulting in an inefficient process. In boiler water application, presence of oxygen in the water will increase corrosion and helps build up boiler scale that inhibits heat transfer. In such instance it is critical to keep DO concentration to a minimum. 20 Some pollutants such as acid mine drainage produce direct chemical demands on oxygen in the water. DO is consumed in the oxidationreduction reactions of introduced chemical compounds such as nitrate 11+ 22(NO3 ) and ammonia (NH4 ), sulfate (SO4 ), and sulfite (SO3 ) and + + ferrous (Fe2 ) and ferric (Fe3 ) ions. [. . . ]