User guide

337
Agilent 7890A Gas Chromatograph
Advanced User Guide
Agilent Technologies
11
Valves
About Valves 338
The Valve Box 339
Heating the valves 339
Valve temperature programming 339
Configuring an Aux thermal zone 340
Valve Control 341
The valve drivers 341
The internal valve drivers 341
The external valve drivers 342
Valve Types 343
Configuring a Valve 344
Controlling a Valve 345
From the keyboard 345
From the run or clock time tables 345
Simple valve: column selection 345
Gas sampling valve 346
Multiposition stream selection valve with sampling valve 347