Optimizing the total run time of a run using a GC 7697A Headspace system

Question

Hello community 
 I ask this question as a non-expert HS user. I have a 7820A GC system with a 7697A Headspace Sampler of 111 vials and I'm running a method that takes 75 minutes to equilibrate the vial in the Headspace sampler and then it passes to the GC to a 7-minute run. The Gc cycle the previous user set was 65 min. Almost 90 minutes are spent in just one sample but I am interested in reducing those times to the minimum possible. Considering the method conditions and the fact we have a 12-vial oven, what GC cycle do you recommend me in order to maximize the performance of the GC. The idea is to have several samples in vial equilibration in order to perform succesive injections and save time. 
 Thank you for your help. 
 Best regards

Lance Nelson · Answer

The GC cycle time is the time it takes for the GC to complete the sample run. From the run start until the GC is ready to run again. For your 7 minute run time, the cycle time is probably 10-15 minutes depending on the time for the oven to return to initial temperature and equilibrate. (You may want to time it to be sure. Add 1 minute of extra time in case the room is a little warmer and the oven takes a little longer to cool. If the headspace sampler gets ready to inject and the GC isn't ready, it can return an error and halt the sequence.) 
 With the 111-vial sampler, the sampler will add the samples to the oven as necessary based on the GC cycle time. After the sequence starts, press the Status key on the 7697A. The vials will be listed with the times as each step progresses. In this example, it would say something like: 1: Equilibrating #:## 2: Starting in #.##

Optimizing the total run time of a run using a GC 7697A Headspace system

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