Gas Chromatography High Baseline
Posted: Fri Jan 11, 2019 1:06 am
Good day all,
I'm asking for help about the unusual high baseline of the front detector of our 7890 GC System. Our system was installed with 2 detectors and is capable of running dual analysis with Ar and He as the carrier gases.
Last June 2018, the front detector(He carrier gas) had an issue and was giving off an erratic output. It was then fixed by a service engineer and replacement parts were installed (motherboard, detector, signal board). These replacement parts were not new and was taken from a laboratory from another site but they were in good working condition.
After installation, the TCD Front Signal was no longer erratic but the baseline was now high. The baseline jumped from 15uV to 280-300uV and it gave a wandering signal.
We tried baking and conditioning the whole system overnight to remove any contamination/impurities that could be present but the baseline remained at 280uV. The oxygen filter was also replaced with a new one. Leak checks were done and no leaks were found.
Any idea on what could be causing the problem?
Thank you.
I'm asking for help about the unusual high baseline of the front detector of our 7890 GC System. Our system was installed with 2 detectors and is capable of running dual analysis with Ar and He as the carrier gases.
Last June 2018, the front detector(He carrier gas) had an issue and was giving off an erratic output. It was then fixed by a service engineer and replacement parts were installed (motherboard, detector, signal board). These replacement parts were not new and was taken from a laboratory from another site but they were in good working condition.
After installation, the TCD Front Signal was no longer erratic but the baseline was now high. The baseline jumped from 15uV to 280-300uV and it gave a wandering signal.
We tried baking and conditioning the whole system overnight to remove any contamination/impurities that could be present but the baseline remained at 280uV. The oxygen filter was also replaced with a new one. Leak checks were done and no leaks were found.
Any idea on what could be causing the problem?
Thank you.