Chromatography Forum

Dear community,

I am facing an odd problem with one of our GC-MS systems, it is an
* Agilent 7000 MSD
* GC 7890a
* GC 80 sampler (actually PAL xt?)

Between samples of a sequence, the GC is occasionally not ready and will never be ready. The status on the GC is "external device not ready". The data acquistion shows a dialog box asking me to override the GC ready. Choosing the override option seemingly leads to a normal run with normal results.

It is a bit annoying to manually override every other sample, if not even every sample.

When the error appears and one pulls the remote start plug from the MS, the autosampler starts its work, but obviously the MS does not switch on the ion source. From my understanding this means that the MS is not "ready" and stops the entire setup from being ready.

Not sure if connectd: quite a while ago an Agilent technician came and updated firmwares, which led to the MSD displaying "GC comm. disabled" (or similiar, I need to double check that). Apparently, I was told, this is not necessarily true.

Does anybody have a hot tip what to do with that info?

Best
cb23

I'm unfamiliar with your exact system. However, I've had similar problems with a 5975C system. Questions first:

- Are you running Masshunter or Chemstation?
- Have you tried rebooting the controller on the MSD or do a hard power cycle?
- Have you tried rebooting the Network Switch (Usually a little box all the LAN cables plug into)?

If you haven't done the last two things, try them first.

Not sure if this will be helpful but just in case - have you configured the readiness options for your methods - maybe there is something in there that would help solve the problem

I agree with rebooting first (including PC).

It is possible that it is trying to reach something that is in your method which is impossible to reach. Does it do the same for other methods?

It's MassHunter as the acq software.

The problem might be actually connected to a faulty network switch. It seems rather old and some LED are not working anymore. It would be a cheap fix and actually I have had some bad experience with faulty switches causing weird errors (on my home network).

I played with the GC readiness options - to no avail. This hints to the MS being the problem (again).

The problems occur in all methods, even the ones created from scratch (default.m).

In the meantime I got a fix because some really important batches were coming up.

I've set the PAL up as an external device and broke the connection "partly" between PAL and PC (the TCP/IP connection, not the remote start) by changing the sync signal from immediate to something else. Now you have to set up and start the job queue on the PAL handheld terminal, but at least we can run batches of 98 samples with out pitching a tent next to the GC.

As soon as these important batches are done, I'll investigate further.

Best,
cb23