Agilent 7890B Gas Chromatograph–Basic Operation
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Agilent 7890B Gas Chromatograph –Basic Operation
Basic Operation
1.
2.
3.
4.
5.
6.
7.
Turn on gasses (He, H2, N2, Air) if not already on. The FID detectors will light automatically
when a method is loaded and the detectors reach operating temperature.
Turn on power to GC with ON/OFF switch (Front, lower left) if not already on. There is no
separate switch for the autosampler.
Select
from Windows desktop to start Chemstation software.
Method/Load Method from menu or use the pull down menu to load an existing method. To
edit the method, select Method/Edit Entire Method from the menu, or one of the icons in the
GC Instrument Diagram Window.
If method uses NPD detector, use the GC front panel keyboard to set the Adjust offset parameter
for the NPD detector to ON. This must be done every time the GC is restarted.
To run a single sample, Select single vial icon Select single-vial icon
in tool bar. Select
RunControl/Sample Info from menu. Enter Sample and operator information. Also enter
desired file name and data subfolder (Typically D:\Data\<yourname>. Sample positions 1-16 are
entered as Vial 101-116. Positions A and (optionally)B are for solvent rinse, Position W is for
waste. Select
To run a sequence, See directions below.
8.
9.
Click on the
buttons to adjust vertical scale. Use
buttons to adjust horizontal scale.
To end a run before the time specified in the method, select Run Control/Stop Run (or F8)
from the menu. The data will be saved. Abort will stop the run without saving data.
10. A report will appear on the screen or printer at the end of the run, as specified in the
Report/Specify Report options in the Data Analysis view. To print, click on the printer icon
on the tool bar. To print details of the method, choose File/Print/Method from the menu.
11. To fix vertical scale in Data Analysis mode (e.g. large solvent peaks) use Report/Specify
Report from menu, then Signal Options button.
Create a New Method
1.
2.
3.
4.
5.
Method/Load Method from menu or use the pull down menu to load to load default
Tufts_FID.M, default Tufts_ECD.M. or default Tufts_NPD.M. Using these methods as templates
will ensure that the switching between FID and ECD or NPD works properly.
Select Method/Edit Entire Method from the menu.
Enter Comments if desired. Select
.
Select Manual or GC Injector as injection source. Select
. If using Manual injection,
gently lift the injector off the GC and lay it aside.
In the main Setup Method screen, there are icons for each module. When in doubt, use default
values.
6. Select
. Enter injection port temperature, pressure and mode.
7. Select
. Enter Flow OR Pressure ORVelocity OR Holdup Time. Other values will be
calculated. Choose flow mode from pull down menu. Select Gas Saver On (recommended).
8. Select
. Enter Temperature ramp values.
Revised 06/03/2015
D. Wilbur
Agilent 7890B Gas Chromatograph–Basic Operation
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9. Select
. Choose front or back detector. Enter temperature and gas flows (typical
300C, 400ml.min air, 30ml/min H2, 25ml/min makeupfor FID).
10. Select
. Select Signal Source, Data Rate (usually 50Hz). Select Save.
11. Select
. Enter items to check before GC indicated Ready.
12. In
tab check any instrument parameters you may wish to plot during run.
13. Select
to exit the Setup Method screen. Move on to Select Signals, Integration,
Report Specification.
14. Save the method (Use Save as)
Data Analysis
1.
To enter the Data analysis view, choose View/Data Analysis from the menu, or select
2.
. By default, the most recently run data will be loaded.
To load other data use File/Load Signal from the menu, or select from the Data Analysis Window
on the left side of the screen.
3.
4.
Select
in main toolbar to toggle Navigation Table, a list of all samples in Single Runs or
Sequence.
To change integration parameters, choose Integration/Integration Events from the menu, or
. Increase Area Reject to eliminate small extraneous peaks. To exit integration events, select
See online help files for more options.
5.
Autointegrate
6.
To manually edit integrals, select
7.
to define or delete integrals.
To adjust vertical scale in Data Analysis display, use the mouse to drag a box on the
chromatogram. To adjust vertical scale in the report, mode use Report/Specify Report from
menu, or
8.
will usually give excellent results.
, and use the manual integration tools,
then Signal Options button.
To Print a report use Report/Specify Report from menu, or
Reporting, set other desired options. Report/View Report File or
or
, select Use Classic
, then Report/Print,
.
Autosampler Instructions
12. Select View/Sampling Diagram from menu.
13. Select multi-vial icon
in tool bar.
14. To run multiple samples:
a. Select Sequence/Sequence Parameters from menu. Enter data file information in
sequence parameter tab(typically path=D:\Data\<your name>, subdirectory=date)\. Enter
report options in sequence output tab. Select
.
b. Select Sequence/Sequence Table from menu. Enter Sample method, and injector
information for each sample. Right click the Line column to append, insert or delete
lines. Sample positions 1-16 are entered in table as 101-116. You need not start with vial
101. Positions A and (optionally) B are for solvent rinse, Position W is for waste. Select
.
Revised 06/03/2015
D. Wilbur
Agilent 7890B Gas Chromatograph–Basic Operation
c.
Select
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. The autosampler will load from vials, according to sequence table.
Chromatograms for each run can be viewed in
sequence can be viewed in
tab. Progress of the
tab.
After Use
1.
2.
3.
Exit Chemstation software. Caution: turning off power to GC while Chemstation is running may
cause software to lock up.
Load method Standby_Cold, or select Instrument/Sleep from menu.
If GC is likely to be idle longer than overnight, turn off power to GC, and turn off gases at the
tanks.
Appendix File Stucture
File structure
Methods stored in D: \Methods\<name>.m
Sequences (sample list for autosampler) stored in D: \Sequences\<name>.s
Data stored in D:\Data\…, as defined in Run Control/Sample Info window. Each run is a directory
consisting of several files, depending on detector.
Acq.txt
Text file with all method parameters
FID1B.ch
Binary chromatogram data file, flame ionization detector
NPD1A.ch
Binary chromatogram data file, nitrogen phosphorous detector
EC1A.ch
Binary chromatogram data file, Electron capture detector
Run.log
Text file run log
Report.txt
Text portion of report, if print to file is specified in Report/Specify Report
Report00.emf
Clipboard file containing chromatograms, if print to file is specified in
Report/Specify Report
Revised 06/03/2015
D. Wilbur