Micromeritics Gemini VII 2390a, Operator'S Manual

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Gemini VII Preparing for Analysis
239-42828-01 - Dec 2012 3-23
• Do not handle heavy objects above the Dewar. If unavoidable, place a protective cover over the
Dewar’s opening. If an object of sufficient weight is accidentally dropped into the Dewar, shattering
may occur.
For stainless steel Dewars:
• Use a plastic stirring rod when stirring substances in a Dewar containing liquefied gases (or other
materials of extremely low temperature).
• Do not handle heavy objects above the Dewar. If unavoidable, place a protective cover over the
Dewar’s opening.
To install the analysis Dewar:
1. Place the analysis Dewar onto the elevator.
2. Fill the Dewar with the analysis bath liquid (liquid nitrogen):
• Large Dewar - fill to about 5 cm (2 in) from the top.
• Small Dewar - fill to about 2 cm (3/4 in) from the top.
3. Insert the dipstick into the Dewar and check the level of the analysis bath liquid. Condensation
should not exceed the Level Indicator mark.
4. For best results, if the Dewar has not been in use for a while, allow approximately 30 minutes for
the temperature of the Dewar to stabilize with the bath liquid. Then recheck the level of the bath
liquid. Add additional liquid if necessary.
Incorrect fluid levels can lead to measurement errors. Check the level of the bath liquid
before each analysis.
Wetness or frozen

condensation indicates
bath liquid level
Level indicator mark