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switch between mg / L and %, or ppm → %. Users can choose mg / L or ppm in parameter
setting P3.1, but only percentage (DO%) is displayed in calibration mode.
5.2
Resolution Selection
The resolution unit can be selected in parameter setting P3.2: 0.01 or 0.1mg/L (ppm),
After
setting, the meter will display resolution of 0.1 or 1 in according to %.
5.3
Temperature Unit Selection
The temperature unit can be selected in parameter setting P4.2: ˚C or ˚F.
5.4
Air Pressure Compensation
The instrument has automatic air pressure compensation function. The air pressure has
been calibrated before the product left the factory. So in general users do not have to
calibrate air pressure any more. If necessary, calibrate it according to standard value
measured by aneroid barometer. Refer to parameter setting P3.5 for the procedure of
aneroid barometer calibration.
5.5
Salinity Compensation
Generally, salinity of freshwater is 0 to 0.5 ppt, salinity of seawater is around 35 ppt. As the
salinity of the solution increases, the level of DO decreases. Refer to parameter setting P3.3,
for selection of auto salinity compensation or manual salinity compensation. If manual
salinity compensation selected in P3.3, please enter the parameter setting P3.4 to input
salinity value (see section 5.5.1); if auto. salinity compensation is selected, users should
connect the salinity probe, then perform calibration in parameter setting P3.4 (see section
5.5.2).