wtw PROTOC 200, Operating Manual

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PROTOC 200 Installation
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3.4.4 Connecting the carrier gas
Carrier gas is used to remove carbon dioxide from the liquid. Gas flow
is regulated by fixed and adjustable flow controllers at strategic loca-
tions in the analyzer. In the majority of applications, the carrier gas is
compressed air. Some applications require zero grade nitrogen or ox-
ygen.
It is important to install an additional pressure regulator close to the an-
alyzer. This is particularly important if the inlet is located outside the
building or if the same gas supply is shared by other equipment. An un-
stable gas flow due to pressure fluctuations will lead to poor reproduc-
ibility of measuring results.
Connecting the gas inlet
1 Install a line from the gas source to the pressure regulator. En-
sure that the tube pressure rating is sufficient and the line ma-
terial clean. Food grade nylon tube is suitable for short
operation times.
2 Connect a gas line to the pressure regulator exit port and bleed
the line briefly to blow out any contamination.
3 Connect the gas line from the pressure regulator to the analyz-
er (Connection C, Figure 3-3). Gas should not be flowing at this
point. The normal pressure setting is 2.2 bar (30 psi).