Hi all,


I just wanted to say thanks for all of your helpful suggestions. I ended up changing the z-offset under the tray menu from 140 to 100, and then the autosampler started working correctly!


Best,

Dana




From: Stable Isotope Geochemistry <[log in to unmask]> on behalf of Dabundo, Richard C <[log in to unmask]>
Sent: Monday, January 23, 2017 11:06 AM
To: [log in to unmask]
Subject: Re: [ISOGEOCHEM] GC PAL problem- collision before z tolerance
 

Hi Dana,


I had this problem recently, and resolved it by decreasing the "Z-retract" setting under "Tray Types" in the hidden menu.


Rich


From: Stable Isotope Geochemistry <[log in to unmask]> on behalf of Dana Biasatti <[log in to unmask]>
Sent: Monday, January 23, 2017 12:58:26 PM
To: [log in to unmask]
Subject: Re: [ISOGEOCHEM] GC PAL problem- collision before z tolerance
 

Thanks, Gerry. I actually changed the bungee cord last week, thinking that it might solve my problem. I will go look at the position of the guide and see if it needs to be reset. If that doesn't work, then I guess I have no choice but to take the thing back apart...

Best,

Dana




From: Stable Isotope Geochemistry <[log in to unmask]> on behalf of gerard olack <[log in to unmask]>
Sent: Monday, January 23, 2017 10:11 AM
To: [log in to unmask]
Subject: Re: [ISOGEOCHEM] GC PAL problem- collision before z tolerance
 

HI All--

Does it fully retract?  If you push up on the bottom needle guide, does it spring back down?  There can be bungee cord problem--they lose their elasticity.  There's also a clamp on one of the rods to let you set the position of the guide.  If it's off, powering down the PAL and letting the assemblage drop down should give you access. 

I haven't taken one apart in years--though I'm about due (bungee cord).  There might be something else dealing with the rod position inside the housing too. 

take care,

gerry


On 1/23/2017 10:47 AM, Jeff Salacup wrote:
Does that black needle guide compress up into the needle housing? Is there a vial in the place where it's looking? Have you tried checking the location of the sample tray in the handheld controller to see if that got changed somehow?

On Mon, Jan 23, 2017 at 11:27 AM, Dana Biasatti <[log in to unmask]> wrote:

Hi Jeff,


It is actually banging, retracting, banging, retracting, then error message. Yes, it happens when it tries to get a sample. I will try using different penetration depths to see if that helps. Thanks!


Dana




From: Stable Isotope Geochemistry <[log in to unmask]> on behalf of Jeff Salacup <[log in to unmask]>
Sent: Monday, January 23, 2017 8:14 AM
To: [log in to unmask]
Subject: Re: [ISOGEOCHEM] GC PAL problem- collision before z tolerance
 
Hi Dana,

I wrestled with our PAL recently. Is it banging or lowering, touching, and retracting? Does this happen when it goes to get a sample? Sometimes the easiest thing to do it just rebuild the locations and method from scratch. For me, it ended up being an adjustment of the needle penetration depth (in the hidden menu) that fixed my Z tolerance and collision issues...

On Mon, Jan 23, 2017 at 9:34 AM, Dana Biasatti <[log in to unmask]> wrote:

Hi all,


I have a GC PAL (A200S) autosampler used with a gas bench. I recently replaced the PAL controller with a new one. All the settings on the GC PAL are the same as they were on the old one. The problem I am having is that every time I try to run a sequence the autosampler will move to the correct position, and the black bottom part of the syringe holder will bang on the sample block twice and then I get a message which reads "Collision before Z tolerance." I have changed the z tolerance setting to quite a few other settings, which hasn't helped. Has anyone seen this before, and do you know how to fix this? Thanks in advance for any advice!


Best,

Dana


Dana Biasatti
Stable Isotope Specialist
Center for Environmental Science and Technology
University of Notre Dame
Notre Dame, IN




--
Jeff




Two things are infinite: the universe and human stupidity; and I'm not sure about the universe. - Einstein



__________________________________________________________________
Jeff Salacup, Ph.D.
Stable Isotope & Biogeochemistry Lab Manager
UMass-Amherst




--
Jeff




Two things are infinite: the universe and human stupidity; and I'm not sure about the universe. - Einstein



__________________________________________________________________
Jeff Salacup, Ph.D.
Stable Isotope & Biogeochemistry Lab Manager
UMass-Amherst