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GCMS-LI is not collecting mass spec data. (chemstation)

KennedyS

I am analyzing terpenes on GCMS-LI 5975C 7890A. 

For some reason it is not collecting mass spec info and the datasim.ms is blank. I see peaks for Retention time, and it will compare the mass spec from the data.sim, but under that window should datasm. peaks and theres nothing. Please help identify why this is happening. I have adjusting the MS SIM/Scan parameters and selected acq. mode to "Scan" which is what i use on my GCMS-HS and works great. But for some reason its not pulling data on the gcms-li. Cannot figure out what's missing. 

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  • 0 in reply to paulsalverda

    INSTRUMENT CONTROL PARAMETERS: GCMS-04
    -----------------------------------------

    C:\MSDCHEM\1\METHODS\60m_VOLITILES_230511_1.M
    Tue May 30 13:44:52 2023

    Control Information
    ------- -----------

    Sample Inlet : GC
    Injection Source : GC ALS
    Mass Spectrometer : Enabled


    No Sample Prep method has been assigned to this method.

    GC
    Oven
    Temperature
    Setpoint On
    (Initial) 40 °C
    Hold Time 2 min
    Post Run 40 °C
    Program
    #1 Rate 6 °C/min
    #1 Value 175 °C
    #1 Hold Time 10 min
    #2 Rate 25 °C/min
    #2 Value 320 °C
    #2 Hold Time 5 min


    Equilibration Time 1 min
    Max Temperature 350 °C
    Slow Fan Disabled
    Cryo Off

    ALS
    Front Injector
    Syringe Size 10 µL
    Injection Volume 1 µL
    Solvent A Washes (PreInj) 3
    Solvent A Washes (PostInj) 3
    Solvent A Volume 8 µL
    Solvent B Washes (PreInj) 3
    Solvent B Washes (PostInj) 3
    Solvent B Volume 8 µL
    Sample Washes 1
    Sample Wash Volume 4 µL
    Sample Pumps 3
    Dwell Time (PreInj) 0 min
    Dwell Time (PostInj) 0 min
    Solvent Wash Draw Speed 300 µL/min
    Solvent Wash Dispense Speed 3000 µL/min
    Sample Wash Draw Speed 300 µL/min
    Sample Wash Dispense Speed 3000 µL/min
    Injection Dispense Speed 6000 µL/min
    Viscosity Delay 2 sec
    Sample Depth Disabled
    Injection Type Standard
    L1 Airgap 0.2 µL

    Tray
    Vial Heater Disabled
    Vial Mixer Disabled

    Sample Overlap
    Mode Sample overlap is not enabled

    ALS Errors Pause for user interaction

    Front SS Inlet He
    Mode Split
    Heater On 250 °C
    Pressure On 17.817 psi
    Total Flow On 36 mL/min
    Septum Purge Flow On 3 mL/min
    Gas Saver On 20 After 1 min mL/min
    Split Ratio 10 :1
    Split Flow 30 mL/min

    Thermal Aux 2 (MSD Transfer Line)
    Temperature
    Setpoint On
    (Initial) 335 °C
    Hold Time 0 min
    Post Run 0 °C


    Column
    Column #1
    Flow
    Setpoint On
    (Initial) 3 mL/min
    Hold Time 3.5 min
    Post Run 2.293 mL/min

    Zebron 7HG-G018-11: 1059811
    ZB-5MSi
    -60 °C—360 °C (360 °C): 60 m x 320 µm x 0.25 µm
    In Front SS Inlet He
    Out MSD
    (Initial) 40 °C
    Pressure 17.817 psi
    Flow 3 mL/min
    Average Velocity 44.411 cm/sec
    Holdup Time 2.2517 min


    Front Detector FID
    ***Excluded from Affecting GC's Readiness State***
    Heater Off
    H2 Flow Off
    Air Flow Off
    Makeup Flow Off
    Carrier Gas Flow Correction Does not affect Makeup or Fuel Flow
    Flame Off
    Electrometer On

    Signals
    Signal #1: Test Plot
    Description Test Plot
    Details
    Save Off
    Data Rate 50 Hz
    Dual Injection Assignment Front Sample

    Signal #2: Test Plot
    Description Test Plot
    Details
    Save Off
    Data Rate 50 Hz
    Dual Injection Assignment Back Sample

    Signal #3: Test Plot
    Description Test Plot
    Details
    Save Off
    Data Rate 50 Hz
    Dual Injection Assignment Back Sample

    Signal #4: Test Plot
    Description Test Plot
    Details
    Save Off
    Data Rate 50 Hz
    Dual Injection Assignment Back Sample


    MS ACQUISITION PARAMETERS


    General Information
    ------- -----------

    Tune File : terp.U
    Acquistion Mode : Scan/SIM in FastScan mode


    MS Information
    -- -----------

    Solvent Delay : 4.00 min

    EMV Mode : Relative
    Relative Voltage : 0
    Resulting EM Voltage : 1235

    [Scan Parameters]

    Low Mass : 40.0
    High Mass : 450.0
    Threshold : 400
    Sample # : 0 A/D Samples 1
    [Sim Parameters]

    GROUP 1
    Group ID : 1
    Resolution : High
    Plot 1 Ion : 314.30
    Ions/Dwell In Group ( Mass, Dwell) ( Mass, Dwell)
    (310.30, 100) (314.30, 100)

    [Data Filters]

    Mass Filter :
    Time Filter : Standard

    [MSZones]

    MS Source : 250 C maximum 250 C
    MS Quad : 200 C maximum 200 C


    END OF MS ACQUISITION PARAMETERS


    TUNE PARAMETERS for SN: US11413920
    -----------------------------

    Trace Ion Detection is OFF.

    EMISSION : 34.610
    ENERGY : 69.922
    REPELLER : 26.605
    IONFOCUS : 90.157
    ENTRANCE_LE : 0.000
    EMVOLTS : 1235.294
    Actual EMV : 1235.29
    GAIN FACTOR : 1.32
    AMUGAIN : 1019.000
    AMUOFFSET : 127.750
    FILAMENT : 1.000
    DCPOLARITY : 0.000
    ENTLENSOFFS : 17.569@ 3 17.569@ 50 13.051@ 69 12.800@131 15.059@219 19.827@414 20.831@502 20.831@1049
    MASSGAIN : -1184.000
    MASSOFFSET : -40.000

    END OF TUNE PARAMETERS
    ------------------------------------

    END OF INSTRUMENT CONTROL PARAMETERS
    ------------------------------------

  • 0 in reply to KennedyS

    Thanks for sharing that. There's nothing specific about not collecting data, but there are some parameters that should be changed.

    Sample Washes 1 If you have enough sample, more washes improves reproducibility.
    Viscosity Delay 2 sec Good.
    Heater On 250 °C But you run the oven to 320?
    Thermal Aux 2 (MSD Transfer Line) (Initial) 335 °C There's no reason to have it hotter than the final oven temperature. The piece of column inside the transferline is under vacuum so the boiling points of compounds are much lower. This affects the source thermal profile, too.
    Flow 3 mL/min This is WAY too high!  The ion source does not like to run higher than about 1.5ml/min.
    Threshold : 400 Try the scan with a lower threshold, like 150.
    (310.30, 100) (314.30, 100) SIM/Scan. 100 ms for 310.3 then 100ms for 314.3, then one scan, then 100ms for 310.3, 100ms for 314.3, then one scan, then repeat.   Try reducing both of the SIM dwell times to 30 ms to get more scans.
    MS Source : 250 C maximum 250 C You could run the source a bit hotter if you'd like. Higher source temperature reduces high mass sensitivity.
    MS Quad : 200 C maximum 200 C There is no reason to run the quad at 200. It reduces the quad lifetime. Please reduce it to 150.

    When the run starts, does the Retention time on the screen change?  Do you get any errors?  Change to just SCAN, A/D 2^2, threshold 75, and try again.

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