Equipment used 7890A natural Gas GC with extended analysis. During operation, FID is frequently shut-off. Try to ignite manually and temporarily solve the problem. But what need to check for identifying the problem?
Equipment used 7890A natural Gas GC with extended analysis. During operation, FID is frequently shut-off. Try to ignite manually and temporarily solve the problem. But what need to check for identifying the problem?
Have you tried lowering the LIT offset? Perhaps it's set a little high, and that would account for the FID shutting itself off repeatedly. You can access the LIT offset by pressing the config button on the front of the GC, and selecting your FID detector. Scroll through the options and you should see LIT offset. Try lowering it down to 0.1 or something like that.
Have you tried lowering the LIT offset? Perhaps it's set a little high, and that would account for the FID shutting itself off repeatedly. You can access the LIT offset by pressing the config button on the front of the GC, and selecting your FID detector. Scroll through the options and you should see LIT offset. Try lowering it down to 0.1 or something like that.
The signal value when lit was 10.7. I wouldn't recommend lowering lit offset to 0.1 as you could possibly have a flame out situation and the detector fuel gas would not turn off (Hydrogen). A lit offset of 2.0 is sufficient in most cases. If the signal is quiet you can go lower, but caution should be used.
It's possible the signal drops lower during a run, or lower than what was shown at that time. I regularly have had several FID's with base signals below 2. In fact the 2 FID's right in front of me both have a signal value of 1.6. I've also never seen a positive signal value for an unlit FID, so 0.1 should still be safe, though if you know your normal baseline, then for sure it can stay elevated.