Brooks Instrument GP200 Series, Руководство по установке и эксплуатации

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Series. If such a valve is not available, shut the valve on the gas
panel. Tag the valve at this point to prevent accidental re-
exposure of the process gas to the gas line.
2. Cycle purge the gas line with dry nitrogen or argon to fully flush
out the process gas. Cycle purging consists of evacuating to a
low pressure adequate to induce out-gassing and then purging
to remove adhered moisture and oxygen. If a toxic or reactive
gas is present and a clogged GP200 Series is suspected, then
proceed with caution. Pump down and purge the GP200 Series
from both downstream and upstream lines. If check valves are
present in the gas line, both pumping down and purging are
required. Pumping down without purging is inadequate. If a
good vacuum source is not available, the GP200 Series can be
de- contaminated by purge only.
3. Repeat the purge cycle several times within 2-4 hours to
complete the cleaning. For toxic and corrosive gasses, it is
recommended to use 100-120 cycles.
Position and Mount the GP200 Series
Position the GP200 Series so that the gas flow is pointed in the
same direction as the flow arrow shown on the GP200 Series rear
label and outer can. The various mounting positions are described
in the figure below.
The standard orientation for the GP200 Series is Horizontal Base
Down (HBD). The accelerometer in the GP200 automatically
determines the orientation of the device and proprietary algorithms
compensate for any potential orientation effects. It is recommended
that the MFC is re-zeroed with process gas following the
recommended Brooks procedure after a change in device mounting
orientation.
Section 2 Installation
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