2 Replies Latest reply on Sep 18, 2017 3:47 PM by james_jenkins

    there is no emission current



      i am using a gc/ms 5975C inert xl ei/ci msd. all the filament i m using is giving me these information 'there is no emission current' just after 2 hours of using a new filament. please can any body help me to check what is going wrong to damage my filamant all the time?

        • Re: there is no emission current

          Hello rogermoise, the first thing I would do is try the other filament if this is on an EI source; this should help confirm that the problem is actually with this particular filament or its wiring and not a broader electronic or other problem. If it's a CI source, it only has one filament of a different design from the EI filaments and there's a “dummy” filament that provides connections for the filament 2 wires.


          The reasons for failure could be many, but among them are:

          • The connection of the filament was loose when installed or grounded to the source body. Ensure that it's connected properly. Below is a wiring diagram for the feedthrough board:

          • The filament was bad and indeed it failed after 2 hours; was it bought from Agilent directly?
          • There's a vacuum leak in the analyzer; if you have an ion gauge, what is your vacuum level (i.e., ion gauge pressure)?
          • The source might need to be cleaned.
          • Re: there is no emission current

            Hi rogermoise

            I went ahead and flagged the “Correct Answer” on this post.  If you still need help though, please let us know and we would be happy to continue working with you.