<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#ffffff" text="#000000">
<!--[if gte mso 9]><xml>
<w:WordDocument>
<w:View>Normal</w:View>
<w:Zoom>0</w:Zoom>
<w:HyphenationZone>21</w:HyphenationZone>
<w:PunctuationKerning/>
<w:ValidateAgainstSchemas/>
<w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid>
<w:IgnoreMixedContent>false</w:IgnoreMixedContent>
<w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText>
<w:Compatibility>
<w:BreakWrappedTables/>
<w:SnapToGridInCell/>
<w:WrapTextWithPunct/>
<w:UseAsianBreakRules/>
<w:DontGrowAutofit/>
</w:Compatibility>
<w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel>
</w:WordDocument>
</xml><![endif]--><!--[if gte mso 9]><xml>
<w:LatentStyles DefLockedState="false" LatentStyleCount="156">
</w:LatentStyles>
</xml><![endif]--><!--[if gte mso 10]>
<style>
/* Style Definitions */
table.MsoNormalTable
{mso-style-name:"Normale Tabelle";
mso-tstyle-rowband-size:0;
mso-tstyle-colband-size:0;
mso-style-noshow:yes;
mso-style-parent:"";
mso-padding-alt:0cm 5.4pt 0cm 5.4pt;
mso-para-margin:0cm;
mso-para-margin-bottom:.0001pt;
mso-pagination:widow-orphan;
font-size:10.0pt;
font-family:"Times New Roman";
mso-ansi-language:#0400;
mso-fareast-language:#0400;
mso-bidi-language:#0400;}
</style>
<![endif]-->
<p class="MsoNormal"><span style="" lang="EN-GB">Hi Ian,<br>
</span></p>
<p class="MsoNormal"><span style="" lang="EN-GB">we bought
an XL-I equipped with an Aviv AU-FDS in 2008 and also suffer
from severe
problems. Either the centrifuge stops spinning or the computer
stops scanning
within a run. This happens after unpredictable times (20 min to
20 hours), at
different rotor speeds (e.g. 22, 35 or 50 krpm), independent
whether we measure
absorbance only or absorbance and interference but not in every
run. Our
machine is still under warranty and Beckman has been trying for
more than one
year to solve this problem. A lot of components of the machine
(all boards, the
display, the radial drive....) were exchanged, but this did not
solve the
problem. After having ruled out that there were problems with
the power supply in our institute,
they admitted that there is a timing problem in the
communication between
centrifuge and computer and that similar problems exist in about
10 machines worldwide.
Therefore, they modified the firmware and installed a new
firmware pre-release (now
the machine stopped scanning regularly in runs which were
performed at 50000
rpm) and afterwards a new version of the GUI, which should solve
this problem. In
first tests with the new firmware/GUI combination the machine
seems to work more
reliable (it did not stop in several test runs at several
speeds), but it
turned out that the new firmware is not able to hand over the
correct value for
w^2t to the computer (a plot of w^2t against the time is not
linear as expected,
but looks like a saw tooth wave). <span style=""> </span>They
are trying to solve this problem for several weeks now and I
still hope that
our centrifuge will work properly soon. Just as a comment: the
Aviv
fluorescence detection system works without any problems.<br>
</span></p>
<p class="MsoNormal"><span style="" lang="EN-GB">Best wishes</span></p>
<p class="MsoNormal"><span style="" lang="EN-GB">Ute</span></p>
<pre class="moz-signature" cols="72">--
PD Dr. rer. nat. Ute Curth
> Medizinische Hochschule Hannover
> Strukturanalyse
> OE 8830
> Carl-Neuberg-Str. 1
> 30625 Hannover
> Germany
>
> Tel.: +49-511-5329372
> Fax : +49-511-5322909</pre>
</body>
</html>