Hanna Instruments HI 903 - Manual (Page 109)

7-3
AUXILIARY FUNCTIONS
7 AUXILIARY FUNCTIONS
7.1 Air Pump
The air pump is used to add or remove the solvent in the titration beaker without exposure
to atmospheric moisture.
To start the air pump, press
from the Idle screen.
The air pump can be stopped by pressing .
7.1.1 Filling the Beaker
To add solvent to the titration vessel:
1. Depress the ‘fill’ button on the top of the pump housing. Pressing the rubberized
button creates a seal which provides the pressure required for the solvent to flow
into the cell. Hold the button down until the level of solvent inside the cell reaches
the ‘min’ indicator line. If the solvent is not flowing, or is flowing very slowly, verify
that the bottle top assemblies are properly assembled and tightly sealed and that
the liquid handling tubing reaches the bottom of the solvent bottle.
2. When the level of solvent inside the titration cell reaches the ‘min’ line release the
Fill button and deactivate the air pump with the option key.
3. The HI 903 will prompt the user to verify that the titration cell has been filled to
the ‘min’ line (approx. 50 mL).
Press to return to Idle screen.
7.1.2 Emptying the Beaker
To remove the waste from the titration vessel:
1. Loosen the waste tube fitting slightly and slide the waste tube down until it reaches
the bottom of the beaker.
2. Press and hold the Empty button until all of the waste is removed from the beaker.
3. Return the waste tube back into its original position and re-tighten the fitting.