[RASMB] Slit assembly electrical problem??

[Hayes, David]

Hi Steve,

A very similar problem has occurred on a centrifuge I had run and the
problems went away after a service visit replacing parts in the
absorbance scanner.  I do not think it was the motor, but only the slit
assembly itself that was worn and jamming.

David

-----Original Message-----
From: rasmb-bounces at rasmb.bbri.org [mailto:rasmb-bounces at rasmb.bbri.org]
On Behalf Of smcbryan
Sent: Wednesday, September 15, 2010 4:48 PM
To: rasmb at server1.bbri.org
Subject: [RASMB] Slit assembly electrical problem??

good day to you all, 
Please see attached .png file showing a zoomed view of the menisci from
a
recent SV experiment. Rather than being peaks, they appear to be
plateaus
of varying widths, and, I believe, are dooming my high resolution
analysis.
Can anyone suggest a likely mechanical or electrical problem that might
cause this, and a solution? Is it possible that my slit assembly motor
is
freezing in place from time to time. Coincident with this observed
phenomena, has been the occurrence of outlier scans, no more than one or
two per experiment, that are baseline absorbance for much of the scan,
then
rapidly jump up to a more proper y-axis position and then follow the
smooth
shape of the other boundaries. Alternatively, in the most recent
experiment
(see second .png) the scans stay at high Abs values coming off the
meniscus
and then drop down to baseline well after the actual boundary position. 
many thanks,
steve

-- 
Steven McBryant, PhD
Director
Protein Production and Characterization Facility
Research Scientist/Scholar
Colorado State University
970-491-5586



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