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signal buffer full

Posted: Wed Nov 19, 2014 8:10 pm
by BurntChem
Hello,

I am using an Agilent / HP 6890 GC-FID. Chemstation version B.04.03-SP1. Occasionally when running a sequence we get an error that states:

Signal 1 buffer full. This stops the sequence and after restarting computer and software it goes away.

Any ideas what might cause this issue and how to fix it? Although the error seems to happen randomly it might occur more when we have long sequences or when internet browsers are open for long periods of time. I can't be sure whats causing it yet.

Thanks for any help. :cyclops:

Re: signal buffer full

Posted: Wed Nov 19, 2014 8:29 pm
by Yama001
I recall that kind of error on some older 5890 systems - it seemed like the data system was acquiring a signal even when you were not collecting data.

We never really figured it out - we just rebooted every morning.

Re: signal buffer full

Posted: Thu Nov 20, 2014 3:45 pm
by GasMan
This could be due to a slow connection between the 6890 and the ChemStation. Data is being collected in the 6890 and is not being sent fast enough to the PC. I have seen this when trying to run a 6890 over a large distance ( the Atlantic ocean), but may also happen if you are collecting data at a high rate. Try reducing the data collection to a lower number. This is done in ChemStation when you select the signals that you want to collect. You will find that you can select data rates from 500 Hz down to 5Hz. You only need the high rates if you are doing fast chromatography with very narrow peaks.

Gasman

Re: signal buffer full

Posted: Thu Nov 20, 2014 3:52 pm
by kubowicz.tomasz
Hello

Check if your PC has some "saving energy" options active. Perhaps hard disc is off after 20 min or so. Set it up to "never"

Regards

Tom

Re: signal buffer full

Posted: Fri Nov 21, 2014 12:36 am
by BurntChem
Thanks for all your replies.

Yama- Yes restarting computer and software does make the problem go away, however its still inconvenient if it occurs in middle of a sequence.

Gasman- GC is connected directly to PC with a cable using HP jetdirect 400N card. Data is being collected at 20Hz so I don't think that is the issue.

Kubowicz- As far as I can tell all the power settings are set so that nothing turns off except monitor if computer is on for long periods of time.

One possible issue that may be related is that if you boot up the computer with the wireless internet connected while the GC is connected via cable the communication between the computer and GC will fail when attempting to load chemstation. If the computer is booted up with the wireless internet disconnected and the GC plugged in the computer and GC will communicate. The wireless internet can then be reconnected and everything appears ok. Not sure why that is occurring either.

Re: signal buffer full

Posted: Fri Nov 21, 2014 7:50 am
by gcguy
We were plagued with this error in the past but never when a sequence was running. My understanding of this error was that the GC dumps data in packets to the PC but only when it is running a sample. The instrument does still collect data but does not send it to the PC when it is idle. The problem for us dissapeared after frimware upgrades but we never really had a fix for it until then. You could try flashing the latest version of firmware but if you are seeing the issue when running I am not sure if this would help. It could be that either of your network cards are on the way out , possibly the one on the PC if the issue goes away after a reboot or even just a bad cable. Or as you say a conflict with the wifi connection.

GCguy

Re: signal buffer full

Posted: Fri Nov 21, 2014 12:45 pm
by tphase
Back in the days when I ran Chemstation on Windows, this problem used to crop up periodically. Never got to the bottom of it but I suspected it was an issue with Windows rather than Chemstation or the GC itself. Since switching to Linux in 2003, I've never seen this error.

Gerry

Re: signal buffer full

Posted: Fri Nov 21, 2014 1:29 pm
by bunnahabhain
I have seen this when trying to run a 6890 over a large distance ( the Atlantic ocean)...
I know it is off-topic, but, did you have a GC instrument in Europe that you tried to control with a computer in the USA? Seems very inconvenient for loading new sample vials :lol:

Re: signal buffer full

Posted: Fri Nov 21, 2014 2:18 pm
by kubowicz.tomasz
Hello

Use command "ping-t IP" during run. It will help you to check if you have network connections problems.

Regards

Tomasz Kubowicz

Re: signal buffer full

Posted: Fri Nov 21, 2014 5:51 pm
by ATAlR
We have same problem with our HP 6890A, but not in 6890N. It happens only if GC is not restarted in approx. 6 month period time. The service guy that used to work with HP, has told me, that internal memory in GC is filling during powered on time, but it is deleted only when you turn GC off.

Re: signal buffer full

Posted: Fri Nov 21, 2014 9:35 pm
by BurntChem
Thanks for help everyone. I think for now I'll just get in habit of restarting GC computer more often.

Re: signal buffer full

Posted: Mon Nov 24, 2014 1:16 pm
by GasMan
bunnahabhain

Actually I was in Germany and the GC was in the USA. I got the guys to load up the autosampler, the only problem was when a syringe did not work as planned. I was developing some ChemStation macros and needed live data for testing.

Gasman