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!



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


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