Galvanic Applied Sciences AccuChrome MA2963, Operation Manual

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Revision 4 97 12/15/2018
9.5 Maintaining Flow Control
Stable helium pressure is very important to maintain repeatable retention times of the
components and a dual stage regulator is recommended. The pressure should be
maintained at the reading indicated in the Configuration Report. For optimum operation of
the system, UHP helium is required. If UHP helium is not readily available, HP helium can be
used with a series of scrubbers. If scrubbers are employed with HP grade helium, please
contact Galvanic Applied Sciences Inc for specific recommendations.
The sample pressure is not as critical as the helium pressure but should be maintained at a
constant pressure between 10 and 100 psig.
Calibration gas pressure should be maintained at the same pressure as the sample gas so
that the flow during calibration will match the flow during normal operation.
It is important to maintain the calibration gas at a relatively constant
temperature. The temperature should be above 59
o
F (15°C) as heavier
hydrocarbons may condense in the sample lines at lower temperatures.
9.6 Replacing Internal Components
The operator may be required to change the valve or columns, which are located in the upper
compartment (Figure 9-2).
Figure 9-2: Columns and Valve
Make certain that the power is turned off before opening the compartment
containing the valve, columns and detector.