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8.8
Notes about conductivity parameter setting
When the content of conductivity parameter setting is different to the
factory default setting, the correspondant code icon will appear on the
upper right of LCD in measurement mode. When more than one
conductivity parameter is changed, only one code will be displayed. You
need to enter the parameter setting and check the settings content or
restore the meter to factory default setting and set the needed parameters again.
9
DO Measurement
9.1
Preparation before use
1) Connect the DO electrode (See Section 5 for connection tutorial). Then Press to power on.
2) Choose DO unit: Hold to switch among mg/L, ppm and %. When the desired unit shows up,
release the button to confirm the unit selection.
9.1.1 Check the sponge
Check on the DO500 DO electrode: see picture (4-1). Screw off the bottom lid of electrode calibration
sleeve, inspect whether the sponge inside is moist. If it is dried out, add in several drops of distilled water
to the sponge to maintain the satured air inside the calibration sleeve (Do NOT add too much water so it
won’t be dripping).
9.1.2 Electrode polarization
After each power on, the DO electrode must be polarized for 5 minutes before measurement or calibration.
So do not to turn off the meter in the middle of your DO measurement. Otherwise, you need to polarize
the DO electrode again after next power on (The auto. power off function in DO mode has been turned
off by default).
9.1.3 How to polarize the DO electrode
Just connect the DO electrode to the powered-on meter without measurement or calibrating.
Electrode polarization is to consume the remaining oxygen inside the inner solution of the membrane cap
so as to ensure fast response and high accuracy. If a new membrane cap is replaced, or new inner
solution is added, the polarization time should be 30 minutes instead of 5 minutes.
