Agilent Technologies 6890 Series Service Manual page 10

Contents
Cleaning an FID jet and collector ...........................................................23
Cleaning the collector....................................................................... 23
Cleaning the jet.................................................................................. 23
320 Nitrogen Phosphorus Detector (NPD)
Theory of operation .................................................................................... 1
EPC detector........................................................................................1
Manually controlled detector ............................................................ 3
Recommended settings .............................................................................. 4
Equilibration time ...............................................................................4
Turning hydrogen off during a solvent peak.................................... 4
Turning hydrogen off between runs ................................................. 4
Bead voltage......................................................................................... 4
Extending the life of the bead ...........................................................4
Temperature programming ................................................................ 5
Jets and collectors .............................................................................. 5
Correcting NPD hardware problems ........................................................ 7
Replacement procedures ......................................................................... 10
Software .............................................................................................10
Replacing the entire detector .......................................................... 10
Replacing the active element (bead) .............................................. 13
Removing the collector assembly ................................................... 16
Replacing the jet................................................................................ 18
Removing the electrometer.............................................................. 19
Removing an EPC flow manifold .................................................... 20
Installing a Type 2 manifold............................................................. 22
Replacing the detector interface board.......................................... 28
Cleaning the NPD jet and collector ........................................................ 30
Cleaning the collector....................................................................... 30
Cleaning the jet.................................................................................. 31
Jun 2001
Contents
Agilent 6890 Gas Chromatograph Service Manual
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