Fig. 3. The oxygen probe’s main components
3-1 – Probe plug
3-2 – Probe handle
3-3 – Temperature-sensing metal
3-4 – Probe head
3-5 – Probe head protective cover
3. Plug the probe plug into the DO probe socket
at the top of the DOM5512SD.
4. Power on the instrument
by pressing the POWER button on the front panel once.
(Powering the unit through a 9V AC/DC adapter—an optional accessory—disables the
POWER button.)
5. Press the
▼
button
(which has the word “Function” stenciled above it) once; the
display will then show “%O2” instead of “mg/L”.
6. Wait at least five minutes
until the display readings stabilize.
7. Use two fingers to press the REC/ENTER and HOLD/ESC
buttons at the same time.
Release your fingers once the display shows the following (indicating that air typically
has an oxygen content of 20.9%):
20.9
CAL
8. Press the REC/ENTER button.
The display will then count down from 30 seconds to 0.
When the countdown is complete, press the
▼
button once to return to the normal
display of “mg/L”.
NORMAL OPERATION
1. To measure the percentage of oxygen dissolved in a liquid:
• Make sure that the probe is full fresh electrolyte and has been calibrated recently.
• Remove the protective cover from the probe head.
• Plug the probe plug into the DO probe socket at the top of the instrument.
• Power on the DOM5512SD by pressing the POWER button on the front panel once.
• Insert the probe at least 4 in. (10cm) into the liquid to be measured.
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