31
The DO probe body is made of PEI.
Use the protective cap when the probe is not in use. To replace the membrane or refill with electrolyte,
proceed as follows:
For a new probe, remove the protective shipping tube by gently twisting and pulling
it off the body of the probe (see fig. 1).
If the membrane was previously installed, unscrew the membrane cap by turning it
clockwise (see fig. 2).
The new membrane cap should be rinsed with electrolyte solution. Refill with clean
electrolyte solution.
Gently tap the sides of the membrane cap to ensure that no air bubbles remain
trapped. Do not tap the bottom directly with your finger, as this will damage the
membrane.
Make sure that the rubber O‑Ring sits properly inside the membrane cap. With the
sensor facing down, slowly screw the membrane cap counterclockwise. Some electrolyte
will overflow.
The platinum cathode (DO Probe Diagram, page 24) should always be bright and
untarnished. If it is tarnished or stained, 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. Afterwards, rinse the probe with deionized or distilled water and install a new
membrane cap using fresh electrolyte and follow DO Probe Preparation page 31.
Important
In order to have accurate and stable measurements, it is important that the membrane
surface to be in perfect condition. This semipermeable membrane isolates the sensor elements from
the environment but allows oxygen to enter. If any dirt is observed on the membrane, rinse carefully
with distilled or deionized water. If imperfections still exist, or any damage is evident (such as
wrinkles or tears‑holes), the membrane should be replaced. Make sure that the O‑Ring sits properly
in the membrane cap.
DISSOLVED OXYGEN PROBE MAINTENANCE
MAINTENANCE
Summary of Contents for edge DO
Page 1: ...DO INSTRUCTION MANUAL ...