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?

  • Hello , 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.
  • I have same problem.

    I cheked both of filament are ok.

    Filament 1 turn on for 3 second and then turn off.

    Second filament don't have same problem.

    It is ok.

    What is the reason?

  • We changed the filament with each other.

    And problem is still exist. It shows that the problem is not from internal.

Reply Children
No Data
Was this helpful?