Varian 450-GC, User Manual

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1177 Split/Splitless Capillary Injector - Injectors
Varian, Inc. User Manual 450-GC Page: 157
1177 Electronic Flow Control (EFC)
The EFC module used with an 1177 Injector is the EFC21 or EFC25.
The EFC21 and EFC25 type are designed specifically for the 1177 and 1079
PTV Injectors to support their various modes of operation. It duplicates the
behavior of the Split/Splitless manual pneumatics system in that there is an inlet
mass flow controller supplying carrier gas to the Injector and a pressure control
valve downstream from the Injector which sets the Injector pressure. As Injector
pressure determines the rate of carrier gas flow through the column, this
pressure is monitored close to the point of injection.
Type EFC21 allows the user to set constant Injector pressure or constant flow.
In addition the split ratio can be programmed.
Figure 20: EFC21 and 1177 in Split mode Flow Diagram
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See Pencil Filters on page 437