HI Anthony--

"Blebbing" from the purge line??? (Is that really a word???)

Our ECS4010 had a cap on the purge line--which we weren't using with the 
Zero Blank autosampler. I had to replace the cap with a very fine 
capillary and keep that line constantly bleeding out at low rates. 
Alternatively, bypass the purge line completely.

Easy test--partially uncap the line an let it flush out a bit, then 
recap it while keeping it the purge on. Problem should go away for a bit.

take care

gerry


Anthony L. Michaud wrote:
>
> Thanks for your appreciation of the problem Bill. J
>
> This seemed like such an interesting problem that I thought someone 
> would have seen it before and would have had a quick response “Yes. 
> This happened to me and this is what was causing it.” But that doesn’t 
> seem to be the case.
>
> I’ve been talking with Bruno about it and am occasionally updating 
> that page with extra information on the problem.
>
> When we get to a solution I’ll post a comment on it. I haven’t tried 
> replacing the combustion reactor or switching the oxygen actuator just 
> yet. We know it is a problem with the EA for sure (rationale given on 
> the webpage). I’m inclined now to bypass section by section of the EA 
> plumbing to try to narrow down where this pulse is coming from.
>
> Anthony
>
> ------------------------------------------------------
>
> Anthony L. Michaud
>
> KFLEB
>
> School of Earth and Space Exploration
>
> Arizona State University
>
> Tempe, AZ 85287-1404
>
> Tel: 480-727-8033
>
> Fax: 480-965-8102
>
> Web: http://kfleb.asu.edu <http://kfleb.asu.edu/>
>
> ***Windsurf Everywhere***
>
> ------------------------------------------------------
>
> ------------------------------------------------------------------------
>
> *From:* Stable Isotope Geochemistry [mailto:[log in to unmask]] 
> *On Behalf Of *William Rugh US EPA
> *Sent:* Wednesday, May 30, 2007 5:06 PM
> *To:* [log in to unmask]
> *Subject:* Re: [ISOGEOCHEM] Spikes on EA
>
>
> Anthony, That's the coolest problem I've seen in a long time! The 
> precise periodicity and amplitude makes me think that the processor in 
> the Costech is triggering a solenoid valve on and off while the EA is 
> in standby mode. It's not impossible that you had a power glitch while 
> it was in standby, and the firmware may be corrupt. It could also be a 
> RC time constant problem with one of the valve controls. If you take 
> the side cover off, can you hear any of the solenoid valves clicking 
> on and off at the 50 sec. interval? Have you tried to power the EA off 
> for 20 sec. or so, and let it re-initialize itself? It's very 
> difficult to think of other problems that would be so precise in 
> timing. Good luck, and thanks for sharing such a unique problem!
>
> William Rugh, Chemist
> Integrated Stable Isotope Research Facility
> US EPA, NHEERL
> Western Ecology Division
> 200 SW 35th St.
> Corvallis, OR 97333
> Office phone: (541) 754-4604
> Lab phone: (541) 754-4515
>