LaMotte Tracer Dissolved Oxygen Meter - Manual (Page 17)

6. Remove a new membrane cap assembly from the red storage container.
Do not touch the membrane part of the assembly as skin oils with
interfere with the oxygen permeability rate of the membrane.
7. Set the membrane cap assembly on a flat surface.
8. Fill the membrane cap assembly with Electrolyte Solution (DO600-EL)
to the bottom of the threads on the inside of the cap. To remove air
bubbles trapped in the threads of the assembly, hold the cap steady with
one hand. Tap the side of the assembly sharply with a pen.
9. Do not move the membrane cap assembly. Dip the electrode into the
assembly and remove it. Repeat this step several times. With each dip,
progressively push the electrode deeper into the electrode solution in
the assembly. This dipping technique will minimize the introduction of
air bubbles into the electrolyte solution. Air bubbles can compromise
dissolved oxygen measurements. Finally, carefully pick up the
membrane cap and slowly screw it onto the electrode, in a
counter-clockwise direction, until it is fully tightened.
10. While replacing the cap, excess electrolyte solution will leak out. This is
normal and desirable since it will minimize air pockets in the solution.
Air pockets can compromise dissolved oxygen measurements. If the
electrolyte solution does not overflow, an insufficient amount was
added. Repeat the process with a new membrane cap assembly if air
bubbles or pockets are visible when the probe is inverted. Membrane
cap assemblies can not be reused.
NOTE: Air bubbles outside the cathode (6mm diameter in the center of
the probe) will not interfere.
11. Rinse off the excess electrolyte solution on the outside of the assembly
and electrode.
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