Isolated LAN connection between PC and GC 6850 (Classic)

I am currently using Agilent 6850 GC (A 05.04). I have connected the GC directly to the PC for the measurements using a crossover ethernet CAT6 cable. According to the manual of Agilent 'Setting up LAN Instrument Network', I can enter the IP address of the computer and use the IP address for the GC by manually entering it on the GC keypad. However, I am not able to connect it. For the configuration of the instrument, I am using the Configuration editor from Chemstation software where I put in the IP address, port number and the License key for the instrument. When I open the Agilent Instrument (Online) module of Agilent Chemstation, it says that 'GC was not found. Check if GC was configured correctly'. I checked for the  IP addresses of both my PC and the GC (the last three digits of the IP addresses are made different as recommended in the operation manual ). However, I did not find any fault. I also tried switching on and off both the PC and the GC, but it didn't help me either. In this case, what will you recommend doing further to successfully set up the connection?

  • Hello,

    Due to the age of this forum post I’ve marked this as resolved.  If you are able to please reply to this thread and let us know how the problem was solved. 


  • The 6850 & 6890 LAN adapters are very often configured to respond to a "BOOTP" server program running on the network they are wired to.

    So upon powerdown the GC loses its previously assigned IP address, and later upon powerup the GC sends a request to whatever network it is connected to, expecting to communicate with a Bootp server which will assign the desired IP address before the Chemstation (or even Openlab) can move forward to the instrument configuration you have entered into the Configuration Editor.

    The Bootp program is usually supposed to run automatically upon reboot of the Windows PC.  It sometimes needs to be installed to Windows separately than the main Chemstation program.

    After reboot of your Windows PC, before starting the Chemstation, make sure your Bootp is running in Windows and settings are appropriate for the particular network & GC.   You can use an older Bootp version from Chemstation A and there is a real-time window that can be observed as the initial communication between the PC & GC takes place.  The bootP window will look about like a blank Notepad.  Then when you powerup the GC, the window will be populated with the IP parameters if successful.  This is how  the IP address is assigned each time after an intentional powerdown of the GC, or a power failure.

    Then start the Chemstation and it's like the power never failed.

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