Milwaukee USER MANUAL PORTABLE DISSOLVED OXYGEN METER MODEL: MW600 Smart DO Meter
PROBE PREPARATION: The meter is supplied with a 9V battery. Slide off the battery compartment cover on the back of the meter. Install the battery into the battery clip connector while observing polarity. D.O. probes are shipped dry. Assemble the probe and prepare it for use, connect it to the meter and proceed as follows. 1. Remove the red and black plastic cap. This cap is used for shipping purposes only and can be thrown away. 2.
PROBE POLARIZATION: • A dissolved oxygen probe must be polarized to function properly. • To polarize the probe, the fully assambled probe must be connected to the meter and the meter must be on. • During polarization (and during measurement), approximately 800 mV is applied to the cathode and anode inside the membrane and a chemical reaction occurs. During the polarization period excess oxygen in the electrolyte is consumed.
Zero Calibration: • Dip the probe into MA9070 zero oxygen solution and stir gently for 2-3 minutes. • Wait for the probe to reach it’s lowest stable reading. • Adjust the zero D.O. calibration trimmer (located on the front panel) until the display reads "0.0". Slope Calibration: It is suggested to perform the slope calibration in water saturated air. • Rinse the probe with a large amount of clean water to remove any residual zero oxygen solution. • Dry the probe tip and allow a few minutes for the D.O.
TAKING MEASUREMENTS: Verify the probe is polarized and the probe and meter have been calibrated. Remove the protective cap from probe. Immerse the tip of the probe in the sample to be tested. For accurate dissolved oxygen measurements a minimum water movement of 0.3 m/sec is required. This is to ensure that the oxygen-depleted membrane surface is constantly replenished. A moving stream will provide adequate circulation.
ALTITUDE COMPENSATION: The displayed measurements are referenced to sea level pressures. At higher elevations, oxygen solubility decreases (thus at higher elevations actual oxygen concentrations are really lower than the displayed value). The table below illustrates the changes in the solubility of oxygen in air saturated fresh water as a result of changes in elevation. The table can also be used to correct the displayed measurement.
SALINITY COMPENSATION: The table below illustrates the change in the solubility of oxygen in air saturated water as a result of chloride concentration or salinity. The table can also be used to correct the displayed measurement. If you are making measurements in salt water and know the chloride concentration (or salinity), you can multiply your reading by the ratio of (ppm at the chloride concentration) / (the ppm at 0 g/L chloride) at the temperature of measurement to compensate for the salt effect.
For example, if the measurement displayed at 10°C is 5 ppm, but the sample has 20 g/L of chloride, to correct your measurement multiply the displayed measurement by the ratio of (ppm reading at 20 g/L) / (ppm reading at 0 g/L) = 5.0 ppm X (8.9 ppm/11.3 ppm) = 3.93 ppm (or 3.9 ppm Chloride or Salinity corrected). PROBE & MEMBRANE MAINTENANCE: The D.O. probe body is made of reinforced plastic for maximum durability. A thermistor temperature sensor provides temperature measurements of the tested sample.
The Platinum cathode should always be bright and untarnished. If it is tarnished or stained, due to contact with certain gases or a damaged membrane cap, the cathode should be cleaned. 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. Rinse the probe with deionized or distilled water and install a new membrane cap using fresh electrolyte (see page 1).
BATTERY REPLACEMENT: When the battery becomes weak the meter will display the low battery indicator " ". When this appears, only a few hours of battery life remain. A low battery will result in unreliable measurements. Prompt battery replacement is required. Battery replacement must take place in a non-hazardous area using an alkaline 9V battery. Turn the meter off, slide the battery compartment cover located at the rear of the meter off and replace the 9V battery with a new one.
SPECIFICATIONS: MW600 RANGE 0.0 to 19.9 mg/L RESOLUTION ACCURACY (@25°C) TEMPERATURE COMPENSATION CALIBRATION LCD PROBE ENVIRONMENT 0.1 mg/L ±1.5% Full Scale Automatic from 0 to 30°C Manual on 2 points (zero and slope) 3½ digits with symbols MA840 (included) 0 to 50°C, 95% RH max.
Milwaukee Authorized Dealer: ISTMW600 01/10
