FID response on HP 5890

[NALI]

Hello all,
Currently my lab is running a few HP 5890 series II+ GCs. This morning as I was religting our FIDs I noticed that one of them was not displaying a signal. This seemed strange to me as each of the detectors gave that satisfying "pop" sound confirming that there was combustion. Also, when a glass vial was held above each detector condensation appropriate to a lit FID appeared. Finally, as I opened ChemStation I noticed that there was no signal being tracked in my online signal window.

I am curious to know, what factors would influence this. Our FID card is set correctly. Next, I reset the column with new ferrules. One possibility that comes to mind while writing this is that the column stationary phase could be shot, clearly influencing the detector's abilities. Obviously a new column would be the easy fix in that case. Has anyone else experienced similar issues?

[Consumer Products Guy]

Make sure that your keyboard function on front of unit is set to something like Signal 1 Det A Signal 2 Det B, etc. Also: Signal:on

[gpronger]

If you tap on the detector lead you should be able to see the signal jump, or if you turn it off, and re-light it, you should see the deflection from lighting the detector. If this isn't happening, one way or another, you're not getting the signal "out" of the detector.

Greg

[at_om]

Hi NALI!

After checking the advices of gpronger and Consumer Products Guy, I would dismantle the FID and namely check if the spring is touching the collector body (metallic part),if it's not this could be the cause for the signal absence. It already happened to my 5890 FID before.

At_om

[Ron]

Most people don't set the detector zero on the 5890, but if you do and the background decreases, then you will get a flat, zero baseline, but will see peaks if you inject a standard.

Another possibility is that the detector lit, but the flame is not in the right vertical position. Rare, but it can happen. Turn off the detector and re-ignite to see if you have signal then.

[Ron]

Most people don't set the detector zero on the 5890, but if you do and the background decreases, then you will get a flat, zero baseline, but will see peaks if you inject a standard.

Another possibility is that the detector lit, but the flame is not in the right vertical position. Rare, but it can happen. Turn off the detector and re-ignite to see if you have signal then.

[NALI]

Thanks for all the responses!

In the past we have had the detector spring incontact with the collector body, and that ended up giving us a maxed out response reading, but it turns out that was not the problem.

As it turns out the method we were running in our OLD OLD OLD version of chem station had not specified to turn on the second detector on the GC. With that changed, both signals are now visible in the online signal window.
Thanks again.

[Consumer Products Guy]

As it turns out the method we were running in our OLD OLD OLD version of chem station had not specified to turn on the second detector on the GC. With that changed, both signals are now visible in the online signal window. Thanks again.

Make sure that your keyboard function on front of unit is set to something like Signal 1 Det A Signal 2 Det B, etc. Also: Signal:on

Yipes, I think I was on the right track !!