Apex Instruments VSC-33 - Adding Reagents; Adjusting reagent levels and conducting a leak check

Adding Reagents
1. With the leveling bottle resting on a firm flat surface, fill the aspirator bottle with the acidic sulfate
solution. Add two or three drops of methyl orange indicator to enhance visibility of the solution in
the pipette. This solution is known as the confining solution. Cap the bottle with one #22 cap and
secure the aspirator bottle in its storage position on the bottom crossbar.
2. Remove the absorption bottle from the carbon dioxide pipette assembly by loosening the #30
bored cap and VC-50F clamp on the middle crossbar. Fill the bottle with KOH absorbing solution
and reattach the bottle to the absorption pipette. In the same fashion, remove the absorption
bottle from the oxygen pipette assembly, and fill the bottle with alkaline paragallol. If carbon
monoxide analyses are required, remove the carbon monoxide absorption bottle from the carbon
monoxide pipette, and fill with acidic cuprous chloride reagent, and reattach to the carbon
monoxide absorption pipette. Ensure that all components are secure in their clamps.
Adjusting reagent levels and conducting a leak check
1. Open the burette valve to ambient air. (Figure 6, Position C) Raise the aspirator bottle to allow
the confining solution to flow from the aspirator bottle to the burette. Carefully observe the
confining solution as it fills the burette. Close the burette valve when the confining solution just
starts to enter the capillary tubing. (Figure 6, Position D)
2. Hold the aspirator bottle at the level of the top of the burette. Open the burette valve to the CO
2
absorption pipette assembly.(Figure 6, Position A) Open the CO
2
valve to the burette. (Figure 6,
Position C). Lower the aspirator bottle to allow the confining solution to flow out of the burette
pulling the CO
2
KOH into the pipette. Watch the level of the KOH solution carefully as it rises in
the CO
2
pipette assembly. When the KOH solution reaches the reference mark on the capillary
tubing, close the CO
2
valve. Attach one section of the Gas Expansion Bag to the hose barb on
the CO
2
pipette bottle using a 2 inch piece of the supplied rubber tubing.
3. Repeat Step 2 for the O
2
pipette and, if required, the CO pipette. During the reagent level
adjustment procedure, the stopcock valve on the oxygen and carbon dioxide absorption pipettes
should be turned to Position C when each of the bottles is being adjusted.
4. After the fluid levels of the absorption pipettes are properly adjusted, open the burette valve and
draw approximately 100 ml of air into the burette by lowering the leveling bottle. When the level
of the burette solution is close to, but not below, the zero mark, close the burette valve. (Figure 6,
Position D) Place the leveling bottle on top of the VersaCase. Observe the levels of the burette
and absorbing solutions for a period of four (4) minutes. The apparatus is considered to have
passed the leak check if the meniscus in the burette rises by no more than 0.2 ml and the levels
of the absorbing solutions do not fall below the capillary tubing.
5. After the leak check, return the confining solution to its proper level by opening the burette valve
to ambient, and raise the aspirator bottle until the level of the confining solution reaches the
capillary tubing. Close the burette valve.
VSC-33
APEX INSTRUMENTS, INC.
11