Agilent Technologies 6890 Series Service Manual page 22

Contents
Valve drivers ................................................................................................ 4
Installing the valve actuator drivers ......................................................... 5
Assemble the valve driver block ....................................................... 5
Install the bracket and cabling .......................................................... 7
Install the valve driver block .............................................................8
Valve actuator alignment..................................................................10
1140 Typical Valve Configurations
1150 Troubleshooting
Chromatographic symptoms ..................................................................... 1
Loss of sensitivity or excessive drift................................................. 2
Loss of peaks in specific areas of the chromatogram .................... 2
Extraneous peaks................................................................................ 3
Peak broadening and tailing .............................................................. 3
Baseline shifts......................................................................................3
Baseline upsets .................................................................................... 4
Variation in peak area and retention time........................................ 4
Pressure check ............................................................................................ 5
1200 Electrical
1210 External Connectors, 6890A and 6890 Plus
Overview ...................................................................................................... 1
Signal 1/Signal 2 analog out ....................................................................... 3
APG remote start/stop ................................................................................ 4
Signal descriptions .............................................................................. 5
APG remote control ............................................................................ 5
RS-232 ..........................................................................................................7
Signal descriptions .............................................................................. 8
External event ............................................................................................. 9
BCD inputs ................................................................................................. 10
GPIB ........................................................................................................... 11
Modular Input/Output (MIO) INET.........................................................12
Modular Input/Output (MIO) LAN .......................................................... 13
Jun 2001
Contents
Agilent 6890 Gas Chromatograph Service Manual
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