Threshold; Cold Trap - Micromeritics FlowSorb III 2305 Operator's Manual

FlowSorb III

Threshold

The Threshold indicator lamp to the left of the display meter flashes when the
accumulated adsorption or desorption signal is greater than the threshold level.
The more rapid the flashing, the greater the magnitude of the signal. This lamp is
designed to begin indicating accumulation of signals as follows:
• x1 scale: between +0.06% and +0.07% nitrogen. It stops indicating when
the signal falls between +0.03% and +0.04% nitrogen.
• x10 scale: between +0.010% and +0.011% nitrogen. It stops indicating
when the signal falls between +0.008% and +0.009% nitrogen.

Cold Trap

A Cold Trap is provided for the removal of vaporous impurities in the analysis
gas stream, especially water vapor. These type impurities tend to be present in
small amounts in commercial gases and are detrimental to surface area evalu-
ation.
A Dewar with a segmented stopper and a longer-than-normal U-tube are provided
for this use. The U-tube is attached by means of the same tightenable connectors
as on sample tubes. The stopper is designed to encase snugly the U-tube stems.
The stopper is segmented so that the Dewar can be initially filled and refilled in
place by removing only the front half of the two-part stopper.
The Dewar is normally filled with liquid nitrogen when making surface area tests
although other coolant baths can be used with special gases.
Mar 2012
Components and Controls
Threshold indicator
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