This Information Applies To: Agilent headspace samplers (HS)
GC cycle time needs to be calculated correctly. Too short a GC cycle time will reduce sample quality and possibly stop the analysis prematurely. Too long GC cycle time can cause reduced sample throughput as vials wait longer than needed before processing.
GC cycle time is the total time required for the GC (or GC/MS) system to return to a ready state after a sample run. HS uses the GC cycle time to calculate throughput and timing. An accurate GC cycle time is crucial to optimize throughput and for correctly processing samples.
Tips: It is better to enter a longer time than needed than to enter too short a time and possibly reduce sample quality.
Steps to follow
1. Check GC Run time.
2. Check GC Oven equilibration time. The default value is 3 minutes.
3. Check GC Cooling time. The cooling time is the time to go down to the original temperature after your analysis is over. It is recommended to calculate this parameter manually.
4. If needed, check GC prep run time and inlet cooling time. However, these parameters are not commonly used and should be added only when necessary.
5. Next, add all timings consolidated from Step 1 to 4.
6. Finally, with the total time calculated, do an addition of 3~5 minutes. The reason for adding this time is that GC is highly influenced by the surrounding environment, so there may be variables. Therefore, this addition of time is required for that variable.
|Caution: This calculation can be flexible because it does not always come out with the same value. The time may increase or decrease depending on the laboratory environment or changes in ambient temperature.|
Follow these steps for Agilent GC/HS systems controlled by the following software products:
To track GC cycle time via OpenLab CDS 2.x
To track GC cycle time via OpenLab ChemStation
To track GC cycle time via Masshunter Acquisition
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