ABB GLA451 User Manual page 98

USER MANUAL | ICOS | INSTRUCTIONS | UM/ICOS-EN REV. B.2
Optional External Throttle Valve
An optional external throttle valve (Figure 92) lets you adjust the gas flow to the analyzer.
Use the throttle valve to restrict the:

Total flow into the analyzer to less than 200 SCCM

Source gas to less than 180 SCCM for proper dynamic dilution control
The flow rate can be measured at the inlet if necessary.
Figure 92: External Throttle Valve
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